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Pickles
CHAPTERS
Pickles Pickles an covered b~ USDA Standardsfw Grades
The preserving of vegetables, meat and fish by salt and acid was one of the principal means of conserving food before the advent of canning and the introduction of mechanical refrigeration. In fact it was about the only way there was of preserving food except by dehydration. It is still a common method of preserving these foods in certain parts of the US and among certain peoples in other countries. Pickled vegetables, such as cabbage and cucumbers, and certain types of pickled meat and fish have always been popular in all lands with all people because they act as an appetizer and fill a certain need when bland fo.od is eaten. The introduction of pasteurization of unfermented types of pickles brought a change into the pickle industry. Prior to that, practically all cucumbers were salted and fermented in barrels or tanks,after which they were marketed or processed and finished. Genuine dills were marketed in glass, cans, or barrels, while salt stock pickles were made into sours, sweets, processed dills or relish. The industry now has four major operating fields. The first is the manufacture of salt stock and genuine dills from green cucumbers by natural fermentation in brine. The second is the manufacture of such staple items as sweet, sour, and mixed pickles from the brinecured cucumbers. The third is the pasteurization of various pickle products from green cucumbers, which is essentially by reason of pasteurization a canning operation. Since these latter types of pickles have become very popular with the consumer, their production has increased until now they account for a large percentage of the total pickle volume. The fourth is refrigerated pickles. This product, introduced in the 1960's, now accounts for about 20 percent of all pickles sold. Cucumber Varieties Used One of the greatest changes that has taken place in the pickle industry in recent years has been the introduction of new varieties. This was made necessary by the large number of diseases of cucumbers and by mechanical harvesting. The two principal diseases in the Northern U.S.are scab rot and mosaic. The
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South is not seriously bothered with scab rot, but has its share of mosaic and other fungus diseases. Research on improved varieties of pickling cucumbers is continuously in progress at several federal and state agricultural experiment stations and seed producing firms. Practically every year, new or existing improved varieties are introduced in one or more of the several cucumber growing and processing regions. For that reason, variety recommendations are not made here. A commercial seed supplier should be consulted for recommended varieties for specific regions. It must be remembered that a variety that does well insofar as yields in the field and processing characteristics,may not do as well in another region.
Raw Material The proper selection of cucumbers is essential in obtaining satisfactory pickles. Cucumbers should be firm, sound, and free from blemishes such as scab rot,wilt, insect bites, etc. They should be delivered to the salting station as soon as possible after picking and should be handled promptly on receipt at the station. They are usually roughly graded for size before salting or further processing.
FIGURE 9.1 - Fiberglass tank being filled with cucumbers for pickling. (Courtesy Owens-Corning Fiberglass Corp.)
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Brining or Curing Cucumbers are brined in fiberglass, polyethylene or wooden tanks ranging in capacity from 200-1200bushels (7,20043,200L).The tanks are filled with green cucumbers graded for size or mixed, fitted with loosely constructed wooden board covers, keyed down firmly with wooden board 2 x 4 in (5x10 cm) or 4 x 4 in (10x10cm). Wooden vats are not recommended. Brine salinity is usually recorded in terms of degree salometer as measured by a hydrometer, calibrated in percentages of saturation with respect to sodium chloride (0-1000'sal). 20', 30' and 40" sal brines approximate brines of 5,8 and 10 percent salt respectively. The general method of salting is to use a 30'40' salometer brine in the bottom of the tank. One pound (0.45kg) of salt per gallon (3.8L) of water will give approximately a 40' salometer solution. Once the cucumbers are added, the brine should decrease to 25' salometer. A layer of 8-10in (20-25cm) of 40' brine is first placed in the tank to prevent bruising of the cucumbersduring filling; the cucumbersare then added. Additional 40' salometer brine is added in sufficient amounts to keep the cucumbers covered. The brine is circulated, by means of a mechanical pump, or by a brine purging device (discussed later) from the bottom of the tank to the top of the cover. Brine strength may be gradually raised after fermentation by adding enough dry salt on the cover to give a holding strength of 16 to 18% at the end of four to six weeks. The high salt concentration is used in frigid climates to prevent freeze damage to the brine stock, but storage at 610% is more common in warmer climates. To produce a reasonably rapid fermentation and thus good, firm stock, the temperature of the brine and pickles should be held at approximately 70-80'F (21-27'C)during the fermentation process. Scum which forms on the top of tanks during fermentation and storage should be removed from time to time. If this is not done, spoilage of the pickles due to utilization of fermentation acid and resultant rise in brine pH, which can cause growth of microorganisms that soften the pickles, may occur. The pickles are cured when the original bright green color has changed to dark olive green, the pickles are translucent in appearance and show no white spots or areas when broken, and no fermentable sugars remain.
Low Salt Brining and Storage Sodium chloride concentrations of 58%during fermentation and 10.15% during subsequent storage of cucumbers have been used to ensure against enzymatic softening. The addition of calcium ions in the form of calcium chloride has been found to allow fermentation and storage at lower salt concentrations. The US pickle industry has adopted the use of calcium chloride on a wide basis, adding 0.20 to 0.35% of the tank contents of this compound.
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Sodium chloride usage has been reduced because of added protection against softening due to calcium ions. Environmental regulations limiting the chloride concentration in process wastewater have forced many U.S.pickle firms to adopt low salt storage after fermentation is completed. Potassium sorbate is often added to control scum growth, especially in warmer climates. This practice is for pickles that will be used in less than one year. Long term storage is not recommended. Environmental concerns have also caused most U.S. pickle firms to reclaim brine. The brine is heated to inactivate spoilage enzymes, pumped through salt to get desired strength and reused.
purging
The production of carbon dioxide in fermentation arises from the cucumber tissue and the fermenting microorganisms, resulting in appearance of carbon dioxide in the brine surrounding the cucumbers. As carbon dioxide concentration increases, the gas pressure increases inside the cucumbers, causing internal gas pockets (bloating). Gas formation inside the tissue is accompanied by an increase in volume of the contents of the fermentation vessel, permitting an estimate of bloater formation as it occurs during fermentation without having to cut the cucumbers. [Bubbling nitrogen gas through the solution in the cucumber tank, removes carbon dioxide from solution, paralleling a decrease in volume inside the vessel, seen as a drop in brine level.] The use of purging has increased steadily and is now used by every large cucumber brining company in the US. Nitrogen is the recommended gas for purging, since it results in reduced levels of oxygen being introduced into the brine. Air purging can result in problems arising from growth of mold and other aerobic microorganisms, and oxidative changes that may result in undesirable flavors and colors. Air purging will effectively prevent bloater formation, but must be used with caution. Many companies use air purging, but on an intermittentbasis with the incorporation of 0.035% potassium sorbate to prevent growth of spoilage molds and yeasts. Various sparging devices are used, including ceramic difhsers and porous plastic. Initially, the sparger was placed in the bottom of the tank, but most companies now use a side-arm gas lift device. The side-arm purger also serves to circulate the brine, and is used for this purpose when needed, in addition to primary use as a means of removing carbon dioxide.
Storing of Pickles in Tanks Tanks used in salting pickles should be provided with a loose cover of boards or planks fitted inside the container a few inches (approximately 10 cm) below the top and with cleats, weights, or other suitable means so that the pickles or
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other vegetables can be kept under the surface of the brine. When the tank is full, the cover is positioned and fastened down. All froth or foam is skimmed off and the top covered with 60' brine. When fermentation has ceased, scum is removed daily. From time to time, sufficient 60' brine is added to keep the cover submerged. Large tanks used for dry salting must be provided with a pump box or shield on one side so that the denser brine may be circulated from the bottom of the tank to the top. When completely cured in a 60' salometer brine, pickles will keep satisfactorily for a year or more. It is recommended that tanks for fermentation, processing or storage of pickles be made of polyethylene or fiberglass, and that wooden tanks not be employed. Fiberglass or polyethylenetanksare more durable, have fewer leakage problems and are easier to clean. The incorporation of wood splinters with the product is eliminated from that source. Problems with banding, which are characteristic of wooden tanks, are also eliminated. Stainless steel bands have been used for wooden tanks successfullyin recent years. The use of fiberglass tanks by the pickle industry is steadily increasing.
FIGURE 9.2 - Fiberglass tanks holding cucumber pickles in brine stock. (Courtesy OwensCorning Fiberglass Corporation)
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Pipes used for brine circulation, purging and for other process purposes typically are made of polyethylene or other noncorrosivematerial. All product contact surfaces in pumps, cutters, and other product preparation and handling equipment should be made of No. 316 stainless steel, or of other corrosion resistant metals or alloys which have the approval of pertinent regulatory agencies. Contact of brine and pickles with iron should be avoided, since low pH, i.e., high acidity of product, causes iron to dissolve rather readily. Dissolved iron is a factor in product discoloration and generation of off-flavors.Boards used to keep pickles immersed in brine should be nailed in such a manner that nails are not directly exposed to corrosive action of brine, which would cause dissolving of iron from nails into brine and pickles. Tanks exposed to rain and snow must have the diluted top layer of brine removed or circulated for mixing. The gas lift side-arm purger can also be used for circulation of brines. Control of Pickle Softening Softening of salt-stock cucumbers during brining and storage is a serious cause of loss to commercial pickle packers. In the past, softeninglosses were unpredictable; cucumbers might or might not go soft in brining tanks. No one knew why it happened or how to prevent it. When cucumbers did soften, packers could either dump the entire lot or, if softening was not too advanced, use the cucumbers for lower priced pickle products. This loss is being investigated through cooperative research by various agencies-USDA’s Food Fermentation Laboratory, Raleigh, North Carolina, operated jointly with the North Carolina Agricultural Experiment Station, Raleigh; and the processing and seed industries. Blossoms are a trouble source; researchers have isolated from cucumber brines two types of enzymes-pectinolytic and cellulolytic- that attack pectin and cellulose in cucumber causing it to soften. Microbial studies indicate that these enzymes are produced chiefly by growth of molds in the cucumber blossoms. These molds flourish in the withering flower as the cucumber develops. When blossoms go into the tank along with the cucumbers, the enzymes diffuse through the brine and thence into the cucumber tissue. Softening enzyme concentration reaches its peak in the brine during the first 24 to 48 hours after tanks are filled. By draining away the original brine at the end of 36 to 48 hours and replacing it with a new brine, researchers markedly reduced the enzymes. A test to detect the presence of softening enzymes has also been devised by these scientists. The practice of draining tanks threatened by softening was widely adopted by the pickle industry during the 1950’s and 1960’s, particularly by Southern
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states operators. It saved thousands of bushels of cucumbers annually at considerable savings during this period, but environmental concerns in recent years have made brine draining impractical. The flowers are now removed from the fruit before brining, reducing the level of softening enzyme. The current use of calcium chloride helps prevent enzymatic softening at relatively low concentrations of salt. Thus, flower removal and addition of calcium chloride to the brine is the most common method of preventing softening. Pasteurization of Cucumber Pickles Extensive university-industrycooperative research on pickle pasteurization has been done by U.S. Department of Agriculture's Food Fermentation Laboratory, in the Department of Food Science,N.C. State University, Raleigh. Researchwith fresh-packdill pickles showed that very short exposures to internal product temperatures in the range of 160'-170'F (71-77'C), with an equilibratedacidity of 0.60% acetic acid or greater,prevented spoilage by natural fermentation and produced pickles of improved quality. Further, it was found that increasingly higher internal product temperatures, from 170' through 200'F (7693'C), resulted in correspondingly increased amounts of bloater damage to the internal structure of the cucumber. As a consequence of this and other research, the U.S. pickle industry at large has adopted a thermal pasteurization process which consists of heating until the internal temperature of a cucumber located in the center of the container reaches 165'F (74'C), holding that temperature for 15 minutes and cooling in water. These recommended pasteurization conditions assume an equilibrated total acidity of 0.60% as acetic acid, sufficient to maintain brine equilibrium pH of 4.0 or lower to assure protection from microbiological spoilage. Lower heat processes are used by some packers in order to increase crispness of the pickles, but at greater risk of spoilage due to underpasteurization. Improper pasteurization may cause product spoilage by growth of yeasts or acid-forming bacteria, or both, that survive inadequate heat treatment. Molds and film yeasts are spoilage factors in cases of poorjar closure. Excessive heating during pasteurization gives products a cooked flavor and a soft texture.
SOUR PICKLES Various types of finished pickle products are made from completely cured brine stock by a series of operations leaching out most of the salt, souring with vinegar, and sweetening with sugar. The leaching or desalting operation is referred to as processing by the industry. The 15 to 18 percent salt in the cured stock is reduced to about 4 percent by at least two changes of water. In the last
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change, the water is heated to about 130'F (54°C). After desalting, the stock is covered with distilled vinegar. This is referred to as souring. Sour pickles and processed dills are made directly from the souring operation and contain about 2.0% and 0.8% acetic acid respectively.
SWEET PICKLES Sweet pickles, as sour pickles, are prepared from brine stock and desalted similarly to sour pickles. Desalted brine stock is pierced using a "pricking" machine to facilitate penetration of the syrup. After washing twice to desalt, pickles are filled into glass containers and syrup at llO'F (43'C) is added, leaving sufficient headspace to achieve the desired vacuum in the container. On weight basis, fill is 60 percent pickles and 40 percent syrup. The syrup is made up of nutritive carbohydrate sweeteners, mostly dextrose and high fructose corn syrup, with spice, essential oils and oleoresins. Spice flavorings used are cloves, coriander, mustard seed, broken ginger root, and mace. Typically, syrup is 57"Brix, and the syrup total acidity is adjusted to approximately 1.6 percent with vinegar. After filling,jars are vacuum capped and immediatelypasteurized by running them through a live steam tunnel. The steam tunnel conveyor speed is adjusted so that containers emerge with product temperature of 145°F (63°C) at the cold point. Eight-oz. (227 g) containers require a residence time to 27 to 38 minutes, depending upon size and shape of product. Cooling by water spray to below 110°F(43'C) follows. In product packed in heavy syrup (57"Brix),after reaching equilibrium in 4 to 6 days, soluble solids measure about 29"Brix, and the salt content is 1.3%.
PROCESS PICKLE RELISH A significant volume of incoming raw cucumbers will be nubs, crooks, and misshaped. Mechanical handling will damage some and some fermentations will produce many bloated cucumbers. This sound salt stock can be sorted and used for various types of relishes. The stock may be desalted and then cut for relish or the salt stock cut and then rapidly de-salted. The stock is usually cut with machines that produce 1/8-3/8 in (0.32-0.46cm) diced cubes. The smaller cuts are for the various types of relish, while larger cuts are for salad cubes. Process sour relish and process dill relish are prepared by mixing the cut relish with vinegar, coloring agents such as turmeric or FD&C certified yellow 5, flavors or essential oils with solubilizingagents, alum and any optional spices. Preservatives such as sodium benzoate and potassium sorbate are often used. Mixing is usually done with ribbon blenders. To allow mechanical pumping and filling, a stabilizer such as Xanthan gum or modified starch is added to the mix.
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Process sweet relish and salad cubes must first be de-watered to prevent excess syrup in the finished product. This is done by running the cubes through tube type squeezers or over a drying belt with vacuum assist under the belt. The de-watered cubes are mixed with high strength (200-300grain) corn syrups, or sugar, coloringagents such as turmeric and/or FD&C certified colors, flavors of solubilizedessential oils, alum, and optional spices. Red bell pepper is usually added to give spot color. Other brined and cured vegetables such as cauliflower,cabbage, and onions may also be added. Mixing is usually done with ribbon blenders. Gums such as Xanthan, guar, or a modified food starch, are usually added as stabilizers; these allow mechanical pumping and filling of the finished product. Practices include the use of preservatives sodium benzoate and potassium sorbate or a process using heat exchangers whereby relish is heated to 160-165'F, held for a time in holding tubes, filled hot, capped and then cooled with water sprays.
DILL PICKLES Dill pickles are of three classifications-fresh pasteurized, genuine and imitation. In the making of genuine dills the curing of the cucumber is carried out differently than for ordinary brine stock. Imitation dills are made from ordinary brine stock. Fresh pasteurized dills are prepared by using brine stock that has been washed twice with water to reduce their salt content. The product is packed in glass containers which are then filled with a dill brine. The dill brine is made up of water, vinegar, dill flavor, and up to 3%salt, if needed. The total acidity at equilibrium should range between 0.5-O.S%, and the salt content between 2-4%. They are often pasteurized to 145'F (63'C) at the cold point. Genuine Dills The larger sizes of pickles are sorted for size and fermented in 45 to 50 gal. (170-190 L) barrels, with dill weed, dill vinegar, and salt. Dill weed and dill vinegar may be purchased in barrels or may be prepared as follows: The weed is cut when the flower hasjust opened, packed into clean, open-headedbarrels and covered with 50 to 60 grain distilled vinegar and 60 pounds (27 kg) of salt per barrel added. The barrels are headed and allowed to stand some months before use. Dill spice used in the process may be purchased or prepared by mixing 1 lb. (0.45 kg) whole allspice, 14 oz. (397 g) whole cloves, 4 oz. (112 g) whole yellow mustard, 2 oz. (56 g) whole celery seed, 4 oz. (112 g) whole black pepper, and 2 oz. (56 g) of broken ginger. The prepared dill weed is drained and about 3 lbs. (1.4 kg) of it placed in the bottom of clean barrels, which are then filled about half 111with cucumbers.
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Six oz. (168 g) of the mixed dill spice as prepared above and 8 lbs. (3.6 kg) of
salt is then added. Three lbs. (1.4 kg) more of dill weed is then packed in and the barrel filled with cucumbers. The barrel is then shaken well and additional dill weed packed on top, together with 6 oz. (168 g) more of dill spice, 8 lbs. (3.6 Kg) of salt and 3 qt. (2.8 L) of dill vinegar drained from the dill weed. The barrel is filled with water to dissolve the salt, or in place of adding dry salt and water, a 29' salometer brine may be added through the bung after the barrel is headed. The barrels are placed on the side with bung up. If dry salt is added, the barrel should be rolled to dissolve the salt. Some packers do not place the bung in the barrel, since the gas formed during fermentation may burst the barrel. If the bung is not inserted, the liquor which foams out during fermentation should be replaced with 20 to 25 degree salometer brine to prevent spoilage. Fermentation takes place best at 80'-85'F (27-29'C). Six to eight weeks are required for curing. Genuine dills, when properly pasteurized and promptly cooled, retain most of their firmness over a storage period of many months. Loss of firmness in genuine dills, either before or after marketing, has been an important reason for a marked reduction in their manufacture. Even though the problem of retaining firmness after packing has been solved by pasteurization, sales resistance has developed because of the milky brine which is the result of the activity of the organisms of natural fermentation. Consumers have been sold on substitutes in the form of imitation dills from salt stock which have clear brines. A genuine dill with an added clear brine is not the answer, because the original flavor produced by the fermentation is changed and the cost of fermenting the dills in barrels exceeds that for substitute products. Imitation Dills Ordinary salt stock of proper size is used for the preparation of imitation dill pickles after the removal of the excess salt as previously outlined under sour pickles. The stock is then put down in barrels with about 10 lbs. (4.5 kg) of dill weed and 1 lb. (0.45 kg) of dill spice per barrel, and covered with a brine made approximately as follows: 1 barrel of dill weed and vinegar, 25 gal. (95 L) of 100 grain distilled vinegar, 350 gal. (1325 L) of water, and 187 lb. (82 kg) of salt. This mixture is cooked for a short time and allowed to stand a few hours to extract the full dill flavor. The drained liquor is used to cover the pickles in the barrels. Premixed spices and dill emulsions are also available on the market. The barrels are then headed and allowed to stand for 2 to 8 weeks when the pickles are packed into containers for shipping. A new brine consisting of 22' salometer solution with enough distilled vinegar to give 8 to 10 grain total acidity and a small amount of dill extract or dill oil is added to give a dill
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flavor. In packing, a piece or two of dill weed is added to each small container such as a can or jar. Pasteurizationand prompt cooling aid in maintaining the firmness of the product.
PASTEURIZED PICKLE PRODUCTS Pasteurization was introduced in the 1940's and rapidly became of major importance in the pickle industry, makinF it possible to add a new line of products to the standard sweets, sours, mixed pickles and relish. The characteristic crispness and fresh appearance and flavor of pasteurized fresh dills and fresh sweet slices have made them very popular with consumers. The moderate requirements of sugar, vinegar and spices in their manufacture have also made them popular with packers. Probably a dozen or more types of pickles made from fresh or partially fermented cucumbers require pasteurization. These products are classed as fresh or unfermented types, partially fermented types, or fully fermented. Pasteurization is required for the first group to prevent fermentation, for the second group to stop the fermentation under way, and for the third group to prevent the further growth of organisms or the action of fermentation byproducts that might reduce firmness during storage. Pasteurization also inactivates enzymes that may cause softening of product. A large portion of the pasteurized pack is unquestionably composed of the sliced fresh cucumber pickle, commonly known as the bread and butter pickles, and the fresh dill pickle. There are a number of closely related types of dills, made from fresh as well as fermented cucumber, that require pasteurization. These differ chiefly in the duration of the natural fermentation period allowed before packing, in the fermented cucumber, or in the amount of acid, salt and spices used in their preparation. Partly fermented dills are often referred to as Polish or Hungarian pickles. The addition of garlic and more spices is often reason for the packer to label any one of the various types of dills a Kosher style product. Ordinarily such a pickle is relatively low in acid and salt and is rather highly seasoned, particularly with garlic. The pasteurization treatment has been developed by carefully conducted experiments under commercial conditions to determine the correct amount of heat required to kill the organisms responsible for spoilage and retain most of the characteristic appearance and crispness of the fresh cucumber tissue.
Fresh Sliced Cucumbers Cucumbers of 1,200 to 1,800 count size, based on a 45 gal. (170 L) cask, are used for making fresh sliced cucumber pickles. The cucumbers are sliced by machine, placed in tanks of about 40 bushel (1,440 L) capacity, covered with a
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30" salometer brine and allowed to remain for several hours. The usual procedure is to cut in the afternoon and permit the sliced cucumbers to remain in the brine overnight. They are then packed into containers and a level teaspoonful of two parts mustard seed and one part celery seed added per 25oz. (0.74 L) jar. A hot liquor at about 160-170'F (71-77°C)is poured on the slices. The liquor should contain sufficient vinegar and sugar to test out about 14 to 15 grains acetic acid and 16-18' Baume when drained from the finished pickle. The final ratio of slices to liquor is generally about 5 to 3 by volume. To maintain a uniform pack, a measured amount of hot liquor is generally first placed in the jars, the sliced cucumbers added until the liquor comes to the top of the jar. The hot jars are capped immediately and ready for pasteurizing so that product at container cold point is heated to 160-170°F(71-77'C), followed by prompt cooling. The brining and holding period may be omitted by substituting a hot water blanch of the fresh sliced pickles. A blanch in 140-180'F (SO-82°C)water for three to six minutes is usually sufficient. Additional salt must be added to the cover liquor to compensate for not brining the slices. Fresh Dills Cucumbers or green tomatoes are used for this product. They are held in tanks for several hours containing about 30' salometer brine and then packed tightly into containers with the desired whole spices and covered with 160170'F (71-77"C) dill liquor containing sufficient vinegar to finish at about 6 to 8 grains acetic acid. The final salt content should be about 2.5-3%. The containers are then capped and pasteurized so that product at the cold point within the container (center of a cucumber or tomato about */Q the distance from the container bottom) is heated to 160-170'F (71-77°C)and promptly cooled. For appearance, a sprig of dill weed may be placed in eachjar. However, the dill flavor is usually added with the hot liquor as emulsified oil of dill. Kosher Style Fresh Dills Garlic, cloves or fresh garlicjuice is added along with the spices. Fermented Dills Overnight dills, Polish or Hungarian style dills, are usually prepared from cucumbers, spices and dill weed covered with about a 20' salometer brine and fermented in barrels for a short time prior to packing. Mixed spices, dill weed, onions, or garlic can be added at the time of preparation. Green tomatoes can be used instead of cucumbers, if desired. The acid content should reach about 4 to 6 grains acetic acid and salt content about 2.5-3%. The partially fermented stock is sorted to eliminate soft pickles and bloaters and packed intojars. The
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product is then covered with the original curing brine which is heated to 160170°F (71-77'C). The jar is capped and pasteurized so that product at cold point of container reaches a temperature of 160-170'F (71-77'C), followed by prompt cooling. Genuine Dills These products must be covered with brine from the original fermentation process which should test out about 8 to 10 grains of lactic acid and reach 1720' salometer. Objectionable cloudiness in the original brine can be removed by filtration. Care should be used to remove all bloaters prior to packing. The original brine is then heated to 160-170'F (71-77'C) and poured over the pickles, the jars capped and the sealed containers are ready for pasteurization. A marked improvement in the retention of firmness in genuine dills during storage can be obtained by pasteurizing the cured product in sealed containers so that product at the cold point of the container is heated to 160-170°F(7177'C), followed by prompt cooling.
PICKLED PEPPERS The U.S. pickle industry has had increasing demand in recent years for various types of pickled peppers, especially in food service. Some of the major types and processing steps follow:
Pepperoncini These peppers are imported from the Mediterranean countries, mainly Greece, and are already brined and cured. They are cured with salt, vinegar, other organic acids and very high levels of sulfites. The peppers are desalted to about 6% salt by leaching in water €or at least two days; this also removes much of the sulfites. The peppers are packed into containers and covered with a brine containing about 5% acetic acid. The equalized product should have about 2.5%acetic acid and 3%salt. Sodium benzoate is added as preservative. The jars are capped and cased. Heating is not usually required. Other Whole Pickled Peppers Jalapeno, sweet cherry, and hot cherry peppers are packed in much the same manner as fresh pack dill pickles. The peppers are blanched in hot water at 150-180'F (66-82'C) for three to six minutes, packed intojars, covered with a hot brine containing about 5%acetic acid and 9% salt, capped, pasteurized at 155'F (68'C) and cooled with water sprays. Sodium benzoate preservative is usually added to the brine. Calcium chloride at 0.2% in the brine helps retain texture.
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Sliced Pickle Pepper Rings Jalapeno and hot cherry peppers are sliced into rings 1/&1/4 in. (0.32-0.64 cm) thick. The slices are packed into containers, covered with a hot brine containing about 5%acetic acid, 910% salt, 0.2% calcium chloride, and sodium benzoate, and capped. Thejars are pasteurized to 155'F (68'C) for ten minutes, and cooled with water sprays. Banana pepper slices are not usually pasteurized, due to loss of texture from heating. Preservation is accomplishedby salt (about 5%) acetic acid (about 3%)in the equalized product and chemical preservatives, covering the slices with a hot brine, 140-160°F(60-71"C),before capping. This process inactivates much of the softening enzymes naturally in the peppers.
CANNING OF PICKLES
(SWEET,SOUR AND DILL) About 99% of pickles and pickle products are packed in glass. No. 10 cans are, however, used for government packs, and for some institutional trade. Smaller sizes of cans may, of course, be used if desired. Heavily lacquered cans are used. A can manufacturer should be consulted. Pickles for institutional use are packed in 2-5 gal. (7.619 L)plastic pails and in flexible pouches of various sizes. Canning Procedure
m s t Methd - Pickles are packed into cans and the proper brine added (sweet brine for sweet pickles, vinegar for sour pickles, and dill liquor together with a little dill weed for dills). The liquor may be added cold and the cans passed through an exhaust box giving a sufficiently long exhaust to obtain a temperature of 165-170'F (7477'C) in the product at the center of the cans as they come from the exhaust box; the liquor may be added hot and the cans exhausted afterwards,in which case a shorter exhaust may be used than if cold liquor is added. Steam exhaust boxes are generally used; the time of exhaust generally necessary for No. 10 cans is 8 to 9 minutes. Water exhaust boxes may be used, if desired, but are not as satisfactory as steam exhaust boxes. After exhausting, all the cans pass immediatelyto the closing machine, and after closing they should be cooled in cold water to 100'F (38'C) or lower, (insufficient cooling results in soft pickles) before casing. Cans should not be cased while they are still wet. - Pickles are packed into cans as in the previous method and the proper brine added. The best practice in order to secure the proper vacuum is to heat the brine to 180-190'F (82-88'C) before filling into cans.
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The cans are then dosed on a vacuum closing machine at a vacuum of 14 to
16 in. (38-40 cm) for No. 10 cans, or at as high vacuum as can be obtained without paneling the sides of the cans.Smaller size cans should be sealed at 20 to 22 in. (51-56 cm) vacuum.
The closed cans should either be given a spray of warm water to remove the brine from the outside or should be wiped with a cloth. Cans of pickles should be stored in a relatively cool place and the best practice is not to pack large quantities in cans for long storage, but only to pack on orders or in such quantities as to take care of orders expected in the near future. ACKNOWLEDGEMENTS The author wishes to acknowledge the contributions to this chapter made by Dr. Henry P. Fleming, ARS, U.S. Department of Agriculture, and Department of Food Science, North Carolina State University, Raleigh; and James B.Joiner, Quality Manager, W.B. Roddenbery Co., Inc., Cairo, GA.
Pickles Pickles an covered b~ USDA Standardsfw Grades
The preserving of vegetables, meat and fish by salt and acid was one of the principal means of conserving food before the advent of canning and the introduction of mechanical refrigeration. In fact it was about the only way there was of preserving food except by dehydration. It is still a common method of preserving these foods in certain parts of the US and among certain peoples in other countries. Pickled vegetables, such as cabbage and cucumbers, and certain types of pickled meat and fish have always been popular in all lands with all people because they act as an appetizer and fill a certain need when bland fo.od is eaten. The introduction of pasteurization of unfermented types of pickles brought a change into the pickle industry. Prior to that, practically all cucumbers were salted and fermented in barrels or tanks,after which they were marketed or processed and finished. Genuine dills were marketed in glass, cans, or barrels, while salt stock pickles were made into sours, sweets, processed dills or relish. The industry now has four major operating fields. The first is the manufacture of salt stock and genuine dills from green cucumbers by natural fermentation in brine. The second is the manufacture of such staple items as sweet, sour, and mixed pickles from the brinecured cucumbers. The third is the pasteurization of various pickle products from green cucumbers, which is essentially by reason of pasteurization a canning operation. Since these latter types of pickles have become very popular with the consumer, their production has increased until now they account for a large percentage of the total pickle volume. The fourth is refrigerated pickles. This product, introduced in the 1960's, now accounts for about 20 percent of all pickles sold. Cucumber Varieties Used One of the greatest changes that has taken place in the pickle industry in recent years has been the introduction of new varieties. This was made necessary by the large number of diseases of cucumbers and by mechanical harvesting. The two principal diseases in the Northern U.S.are scab rot and mosaic. The
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South is not seriously bothered with scab rot, but has its share of mosaic and other fungus diseases. Research on improved varieties of pickling cucumbers is continuously in progress at several federal and state agricultural experiment stations and seed producing firms. Practically every year, new or existing improved varieties are introduced in one or more of the several cucumber growing and processing regions. For that reason, variety recommendations are not made here. A commercial seed supplier should be consulted for recommended varieties for specific regions. It must be remembered that a variety that does well insofar as yields in the field and processing characteristics,may not do as well in another region.
Raw Material The proper selection of cucumbers is essential in obtaining satisfactory pickles. Cucumbers should be firm, sound, and free from blemishes such as scab rot,wilt, insect bites, etc. They should be delivered to the salting station as soon as possible after picking and should be handled promptly on receipt at the station. They are usually roughly graded for size before salting or further processing.
FIGURE 9.1 - Fiberglass tank being filled with cucumbers for pickling. (Courtesy Owens-Corning Fiberglass Corp.)
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Brining or Curing Cucumbers are brined in fiberglass, polyethylene or wooden tanks ranging in capacity from 200-1200bushels (7,20043,200L).The tanks are filled with green cucumbers graded for size or mixed, fitted with loosely constructed wooden board covers, keyed down firmly with wooden board 2 x 4 in (5x10 cm) or 4 x 4 in (10x10cm). Wooden vats are not recommended. Brine salinity is usually recorded in terms of degree salometer as measured by a hydrometer, calibrated in percentages of saturation with respect to sodium chloride (0-1000'sal). 20', 30' and 40" sal brines approximate brines of 5,8 and 10 percent salt respectively. The general method of salting is to use a 30'40' salometer brine in the bottom of the tank. One pound (0.45kg) of salt per gallon (3.8L) of water will give approximately a 40' salometer solution. Once the cucumbers are added, the brine should decrease to 25' salometer. A layer of 8-10in (20-25cm) of 40' brine is first placed in the tank to prevent bruising of the cucumbersduring filling; the cucumbersare then added. Additional 40' salometer brine is added in sufficient amounts to keep the cucumbers covered. The brine is circulated, by means of a mechanical pump, or by a brine purging device (discussed later) from the bottom of the tank to the top of the cover. Brine strength may be gradually raised after fermentation by adding enough dry salt on the cover to give a holding strength of 16 to 18% at the end of four to six weeks. The high salt concentration is used in frigid climates to prevent freeze damage to the brine stock, but storage at 610% is more common in warmer climates. To produce a reasonably rapid fermentation and thus good, firm stock, the temperature of the brine and pickles should be held at approximately 70-80'F (21-27'C)during the fermentation process. Scum which forms on the top of tanks during fermentation and storage should be removed from time to time. If this is not done, spoilage of the pickles due to utilization of fermentation acid and resultant rise in brine pH, which can cause growth of microorganisms that soften the pickles, may occur. The pickles are cured when the original bright green color has changed to dark olive green, the pickles are translucent in appearance and show no white spots or areas when broken, and no fermentable sugars remain.
Low Salt Brining and Storage Sodium chloride concentrations of 58%during fermentation and 10.15% during subsequent storage of cucumbers have been used to ensure against enzymatic softening. The addition of calcium ions in the form of calcium chloride has been found to allow fermentation and storage at lower salt concentrations. The US pickle industry has adopted the use of calcium chloride on a wide basis, adding 0.20 to 0.35% of the tank contents of this compound.
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Sodium chloride usage has been reduced because of added protection against softening due to calcium ions. Environmental regulations limiting the chloride concentration in process wastewater have forced many U.S.pickle firms to adopt low salt storage after fermentation is completed. Potassium sorbate is often added to control scum growth, especially in warmer climates. This practice is for pickles that will be used in less than one year. Long term storage is not recommended. Environmental concerns have also caused most U.S. pickle firms to reclaim brine. The brine is heated to inactivate spoilage enzymes, pumped through salt to get desired strength and reused.
purging
The production of carbon dioxide in fermentation arises from the cucumber tissue and the fermenting microorganisms, resulting in appearance of carbon dioxide in the brine surrounding the cucumbers. As carbon dioxide concentration increases, the gas pressure increases inside the cucumbers, causing internal gas pockets (bloating). Gas formation inside the tissue is accompanied by an increase in volume of the contents of the fermentation vessel, permitting an estimate of bloater formation as it occurs during fermentation without having to cut the cucumbers. [Bubbling nitrogen gas through the solution in the cucumber tank, removes carbon dioxide from solution, paralleling a decrease in volume inside the vessel, seen as a drop in brine level.] The use of purging has increased steadily and is now used by every large cucumber brining company in the US. Nitrogen is the recommended gas for purging, since it results in reduced levels of oxygen being introduced into the brine. Air purging can result in problems arising from growth of mold and other aerobic microorganisms, and oxidative changes that may result in undesirable flavors and colors. Air purging will effectively prevent bloater formation, but must be used with caution. Many companies use air purging, but on an intermittentbasis with the incorporation of 0.035% potassium sorbate to prevent growth of spoilage molds and yeasts. Various sparging devices are used, including ceramic difhsers and porous plastic. Initially, the sparger was placed in the bottom of the tank, but most companies now use a side-arm gas lift device. The side-arm purger also serves to circulate the brine, and is used for this purpose when needed, in addition to primary use as a means of removing carbon dioxide.
Storing of Pickles in Tanks Tanks used in salting pickles should be provided with a loose cover of boards or planks fitted inside the container a few inches (approximately 10 cm) below the top and with cleats, weights, or other suitable means so that the pickles or
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other vegetables can be kept under the surface of the brine. When the tank is full, the cover is positioned and fastened down. All froth or foam is skimmed off and the top covered with 60' brine. When fermentation has ceased, scum is removed daily. From time to time, sufficient 60' brine is added to keep the cover submerged. Large tanks used for dry salting must be provided with a pump box or shield on one side so that the denser brine may be circulated from the bottom of the tank to the top. When completely cured in a 60' salometer brine, pickles will keep satisfactorily for a year or more. It is recommended that tanks for fermentation, processing or storage of pickles be made of polyethylene or fiberglass, and that wooden tanks not be employed. Fiberglass or polyethylenetanksare more durable, have fewer leakage problems and are easier to clean. The incorporation of wood splinters with the product is eliminated from that source. Problems with banding, which are characteristic of wooden tanks, are also eliminated. Stainless steel bands have been used for wooden tanks successfullyin recent years. The use of fiberglass tanks by the pickle industry is steadily increasing.
FIGURE 9.2 - Fiberglass tanks holding cucumber pickles in brine stock. (Courtesy OwensCorning Fiberglass Corporation)
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Pipes used for brine circulation, purging and for other process purposes typically are made of polyethylene or other noncorrosivematerial. All product contact surfaces in pumps, cutters, and other product preparation and handling equipment should be made of No. 316 stainless steel, or of other corrosion resistant metals or alloys which have the approval of pertinent regulatory agencies. Contact of brine and pickles with iron should be avoided, since low pH, i.e., high acidity of product, causes iron to dissolve rather readily. Dissolved iron is a factor in product discoloration and generation of off-flavors.Boards used to keep pickles immersed in brine should be nailed in such a manner that nails are not directly exposed to corrosive action of brine, which would cause dissolving of iron from nails into brine and pickles. Tanks exposed to rain and snow must have the diluted top layer of brine removed or circulated for mixing. The gas lift side-arm purger can also be used for circulation of brines. Control of Pickle Softening Softening of salt-stock cucumbers during brining and storage is a serious cause of loss to commercial pickle packers. In the past, softeninglosses were unpredictable; cucumbers might or might not go soft in brining tanks. No one knew why it happened or how to prevent it. When cucumbers did soften, packers could either dump the entire lot or, if softening was not too advanced, use the cucumbers for lower priced pickle products. This loss is being investigated through cooperative research by various agencies-USDA’s Food Fermentation Laboratory, Raleigh, North Carolina, operated jointly with the North Carolina Agricultural Experiment Station, Raleigh; and the processing and seed industries. Blossoms are a trouble source; researchers have isolated from cucumber brines two types of enzymes-pectinolytic and cellulolytic- that attack pectin and cellulose in cucumber causing it to soften. Microbial studies indicate that these enzymes are produced chiefly by growth of molds in the cucumber blossoms. These molds flourish in the withering flower as the cucumber develops. When blossoms go into the tank along with the cucumbers, the enzymes diffuse through the brine and thence into the cucumber tissue. Softening enzyme concentration reaches its peak in the brine during the first 24 to 48 hours after tanks are filled. By draining away the original brine at the end of 36 to 48 hours and replacing it with a new brine, researchers markedly reduced the enzymes. A test to detect the presence of softening enzymes has also been devised by these scientists. The practice of draining tanks threatened by softening was widely adopted by the pickle industry during the 1950’s and 1960’s, particularly by Southern
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states operators. It saved thousands of bushels of cucumbers annually at considerable savings during this period, but environmental concerns in recent years have made brine draining impractical. The flowers are now removed from the fruit before brining, reducing the level of softening enzyme. The current use of calcium chloride helps prevent enzymatic softening at relatively low concentrations of salt. Thus, flower removal and addition of calcium chloride to the brine is the most common method of preventing softening. Pasteurization of Cucumber Pickles Extensive university-industrycooperative research on pickle pasteurization has been done by U.S. Department of Agriculture's Food Fermentation Laboratory, in the Department of Food Science,N.C. State University, Raleigh. Researchwith fresh-packdill pickles showed that very short exposures to internal product temperatures in the range of 160'-170'F (71-77'C), with an equilibratedacidity of 0.60% acetic acid or greater,prevented spoilage by natural fermentation and produced pickles of improved quality. Further, it was found that increasingly higher internal product temperatures, from 170' through 200'F (7693'C), resulted in correspondingly increased amounts of bloater damage to the internal structure of the cucumber. As a consequence of this and other research, the U.S. pickle industry at large has adopted a thermal pasteurization process which consists of heating until the internal temperature of a cucumber located in the center of the container reaches 165'F (74'C), holding that temperature for 15 minutes and cooling in water. These recommended pasteurization conditions assume an equilibrated total acidity of 0.60% as acetic acid, sufficient to maintain brine equilibrium pH of 4.0 or lower to assure protection from microbiological spoilage. Lower heat processes are used by some packers in order to increase crispness of the pickles, but at greater risk of spoilage due to underpasteurization. Improper pasteurization may cause product spoilage by growth of yeasts or acid-forming bacteria, or both, that survive inadequate heat treatment. Molds and film yeasts are spoilage factors in cases of poorjar closure. Excessive heating during pasteurization gives products a cooked flavor and a soft texture.
SOUR PICKLES Various types of finished pickle products are made from completely cured brine stock by a series of operations leaching out most of the salt, souring with vinegar, and sweetening with sugar. The leaching or desalting operation is referred to as processing by the industry. The 15 to 18 percent salt in the cured stock is reduced to about 4 percent by at least two changes of water. In the last
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change, the water is heated to about 130'F (54°C). After desalting, the stock is covered with distilled vinegar. This is referred to as souring. Sour pickles and processed dills are made directly from the souring operation and contain about 2.0% and 0.8% acetic acid respectively.
SWEET PICKLES Sweet pickles, as sour pickles, are prepared from brine stock and desalted similarly to sour pickles. Desalted brine stock is pierced using a "pricking" machine to facilitate penetration of the syrup. After washing twice to desalt, pickles are filled into glass containers and syrup at llO'F (43'C) is added, leaving sufficient headspace to achieve the desired vacuum in the container. On weight basis, fill is 60 percent pickles and 40 percent syrup. The syrup is made up of nutritive carbohydrate sweeteners, mostly dextrose and high fructose corn syrup, with spice, essential oils and oleoresins. Spice flavorings used are cloves, coriander, mustard seed, broken ginger root, and mace. Typically, syrup is 57"Brix, and the syrup total acidity is adjusted to approximately 1.6 percent with vinegar. After filling,jars are vacuum capped and immediatelypasteurized by running them through a live steam tunnel. The steam tunnel conveyor speed is adjusted so that containers emerge with product temperature of 145°F (63°C) at the cold point. Eight-oz. (227 g) containers require a residence time to 27 to 38 minutes, depending upon size and shape of product. Cooling by water spray to below 110°F(43'C) follows. In product packed in heavy syrup (57"Brix),after reaching equilibrium in 4 to 6 days, soluble solids measure about 29"Brix, and the salt content is 1.3%.
PROCESS PICKLE RELISH A significant volume of incoming raw cucumbers will be nubs, crooks, and misshaped. Mechanical handling will damage some and some fermentations will produce many bloated cucumbers. This sound salt stock can be sorted and used for various types of relishes. The stock may be desalted and then cut for relish or the salt stock cut and then rapidly de-salted. The stock is usually cut with machines that produce 1/8-3/8 in (0.32-0.46cm) diced cubes. The smaller cuts are for the various types of relish, while larger cuts are for salad cubes. Process sour relish and process dill relish are prepared by mixing the cut relish with vinegar, coloring agents such as turmeric or FD&C certified yellow 5, flavors or essential oils with solubilizingagents, alum and any optional spices. Preservatives such as sodium benzoate and potassium sorbate are often used. Mixing is usually done with ribbon blenders. To allow mechanical pumping and filling, a stabilizer such as Xanthan gum or modified starch is added to the mix.
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Process sweet relish and salad cubes must first be de-watered to prevent excess syrup in the finished product. This is done by running the cubes through tube type squeezers or over a drying belt with vacuum assist under the belt. The de-watered cubes are mixed with high strength (200-300grain) corn syrups, or sugar, coloringagents such as turmeric and/or FD&C certified colors, flavors of solubilizedessential oils, alum, and optional spices. Red bell pepper is usually added to give spot color. Other brined and cured vegetables such as cauliflower,cabbage, and onions may also be added. Mixing is usually done with ribbon blenders. Gums such as Xanthan, guar, or a modified food starch, are usually added as stabilizers; these allow mechanical pumping and filling of the finished product. Practices include the use of preservatives sodium benzoate and potassium sorbate or a process using heat exchangers whereby relish is heated to 160-165'F, held for a time in holding tubes, filled hot, capped and then cooled with water sprays.
DILL PICKLES Dill pickles are of three classifications-fresh pasteurized, genuine and imitation. In the making of genuine dills the curing of the cucumber is carried out differently than for ordinary brine stock. Imitation dills are made from ordinary brine stock. Fresh pasteurized dills are prepared by using brine stock that has been washed twice with water to reduce their salt content. The product is packed in glass containers which are then filled with a dill brine. The dill brine is made up of water, vinegar, dill flavor, and up to 3%salt, if needed. The total acidity at equilibrium should range between 0.5-O.S%, and the salt content between 2-4%. They are often pasteurized to 145'F (63'C) at the cold point. Genuine Dills The larger sizes of pickles are sorted for size and fermented in 45 to 50 gal. (170-190 L) barrels, with dill weed, dill vinegar, and salt. Dill weed and dill vinegar may be purchased in barrels or may be prepared as follows: The weed is cut when the flower hasjust opened, packed into clean, open-headedbarrels and covered with 50 to 60 grain distilled vinegar and 60 pounds (27 kg) of salt per barrel added. The barrels are headed and allowed to stand some months before use. Dill spice used in the process may be purchased or prepared by mixing 1 lb. (0.45 kg) whole allspice, 14 oz. (397 g) whole cloves, 4 oz. (112 g) whole yellow mustard, 2 oz. (56 g) whole celery seed, 4 oz. (112 g) whole black pepper, and 2 oz. (56 g) of broken ginger. The prepared dill weed is drained and about 3 lbs. (1.4 kg) of it placed in the bottom of clean barrels, which are then filled about half 111with cucumbers.
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Six oz. (168 g) of the mixed dill spice as prepared above and 8 lbs. (3.6 kg) of
salt is then added. Three lbs. (1.4 kg) more of dill weed is then packed in and the barrel filled with cucumbers. The barrel is then shaken well and additional dill weed packed on top, together with 6 oz. (168 g) more of dill spice, 8 lbs. (3.6 Kg) of salt and 3 qt. (2.8 L) of dill vinegar drained from the dill weed. The barrel is filled with water to dissolve the salt, or in place of adding dry salt and water, a 29' salometer brine may be added through the bung after the barrel is headed. The barrels are placed on the side with bung up. If dry salt is added, the barrel should be rolled to dissolve the salt. Some packers do not place the bung in the barrel, since the gas formed during fermentation may burst the barrel. If the bung is not inserted, the liquor which foams out during fermentation should be replaced with 20 to 25 degree salometer brine to prevent spoilage. Fermentation takes place best at 80'-85'F (27-29'C). Six to eight weeks are required for curing. Genuine dills, when properly pasteurized and promptly cooled, retain most of their firmness over a storage period of many months. Loss of firmness in genuine dills, either before or after marketing, has been an important reason for a marked reduction in their manufacture. Even though the problem of retaining firmness after packing has been solved by pasteurization, sales resistance has developed because of the milky brine which is the result of the activity of the organisms of natural fermentation. Consumers have been sold on substitutes in the form of imitation dills from salt stock which have clear brines. A genuine dill with an added clear brine is not the answer, because the original flavor produced by the fermentation is changed and the cost of fermenting the dills in barrels exceeds that for substitute products. Imitation Dills Ordinary salt stock of proper size is used for the preparation of imitation dill pickles after the removal of the excess salt as previously outlined under sour pickles. The stock is then put down in barrels with about 10 lbs. (4.5 kg) of dill weed and 1 lb. (0.45 kg) of dill spice per barrel, and covered with a brine made approximately as follows: 1 barrel of dill weed and vinegar, 25 gal. (95 L) of 100 grain distilled vinegar, 350 gal. (1325 L) of water, and 187 lb. (82 kg) of salt. This mixture is cooked for a short time and allowed to stand a few hours to extract the full dill flavor. The drained liquor is used to cover the pickles in the barrels. Premixed spices and dill emulsions are also available on the market. The barrels are then headed and allowed to stand for 2 to 8 weeks when the pickles are packed into containers for shipping. A new brine consisting of 22' salometer solution with enough distilled vinegar to give 8 to 10 grain total acidity and a small amount of dill extract or dill oil is added to give a dill
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flavor. In packing, a piece or two of dill weed is added to each small container such as a can or jar. Pasteurizationand prompt cooling aid in maintaining the firmness of the product.
PASTEURIZED PICKLE PRODUCTS Pasteurization was introduced in the 1940's and rapidly became of major importance in the pickle industry, makinF it possible to add a new line of products to the standard sweets, sours, mixed pickles and relish. The characteristic crispness and fresh appearance and flavor of pasteurized fresh dills and fresh sweet slices have made them very popular with consumers. The moderate requirements of sugar, vinegar and spices in their manufacture have also made them popular with packers. Probably a dozen or more types of pickles made from fresh or partially fermented cucumbers require pasteurization. These products are classed as fresh or unfermented types, partially fermented types, or fully fermented. Pasteurization is required for the first group to prevent fermentation, for the second group to stop the fermentation under way, and for the third group to prevent the further growth of organisms or the action of fermentation byproducts that might reduce firmness during storage. Pasteurization also inactivates enzymes that may cause softening of product. A large portion of the pasteurized pack is unquestionably composed of the sliced fresh cucumber pickle, commonly known as the bread and butter pickles, and the fresh dill pickle. There are a number of closely related types of dills, made from fresh as well as fermented cucumber, that require pasteurization. These differ chiefly in the duration of the natural fermentation period allowed before packing, in the fermented cucumber, or in the amount of acid, salt and spices used in their preparation. Partly fermented dills are often referred to as Polish or Hungarian pickles. The addition of garlic and more spices is often reason for the packer to label any one of the various types of dills a Kosher style product. Ordinarily such a pickle is relatively low in acid and salt and is rather highly seasoned, particularly with garlic. The pasteurization treatment has been developed by carefully conducted experiments under commercial conditions to determine the correct amount of heat required to kill the organisms responsible for spoilage and retain most of the characteristic appearance and crispness of the fresh cucumber tissue.
Fresh Sliced Cucumbers Cucumbers of 1,200 to 1,800 count size, based on a 45 gal. (170 L) cask, are used for making fresh sliced cucumber pickles. The cucumbers are sliced by machine, placed in tanks of about 40 bushel (1,440 L) capacity, covered with a
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30" salometer brine and allowed to remain for several hours. The usual procedure is to cut in the afternoon and permit the sliced cucumbers to remain in the brine overnight. They are then packed into containers and a level teaspoonful of two parts mustard seed and one part celery seed added per 25oz. (0.74 L) jar. A hot liquor at about 160-170'F (71-77°C)is poured on the slices. The liquor should contain sufficient vinegar and sugar to test out about 14 to 15 grains acetic acid and 16-18' Baume when drained from the finished pickle. The final ratio of slices to liquor is generally about 5 to 3 by volume. To maintain a uniform pack, a measured amount of hot liquor is generally first placed in the jars, the sliced cucumbers added until the liquor comes to the top of the jar. The hot jars are capped immediately and ready for pasteurizing so that product at container cold point is heated to 160-170°F(71-77'C), followed by prompt cooling. The brining and holding period may be omitted by substituting a hot water blanch of the fresh sliced pickles. A blanch in 140-180'F (SO-82°C)water for three to six minutes is usually sufficient. Additional salt must be added to the cover liquor to compensate for not brining the slices. Fresh Dills Cucumbers or green tomatoes are used for this product. They are held in tanks for several hours containing about 30' salometer brine and then packed tightly into containers with the desired whole spices and covered with 160170'F (71-77"C) dill liquor containing sufficient vinegar to finish at about 6 to 8 grains acetic acid. The final salt content should be about 2.5-3%. The containers are then capped and pasteurized so that product at the cold point within the container (center of a cucumber or tomato about */Q the distance from the container bottom) is heated to 160-170'F (71-77°C)and promptly cooled. For appearance, a sprig of dill weed may be placed in eachjar. However, the dill flavor is usually added with the hot liquor as emulsified oil of dill. Kosher Style Fresh Dills Garlic, cloves or fresh garlicjuice is added along with the spices. Fermented Dills Overnight dills, Polish or Hungarian style dills, are usually prepared from cucumbers, spices and dill weed covered with about a 20' salometer brine and fermented in barrels for a short time prior to packing. Mixed spices, dill weed, onions, or garlic can be added at the time of preparation. Green tomatoes can be used instead of cucumbers, if desired. The acid content should reach about 4 to 6 grains acetic acid and salt content about 2.5-3%. The partially fermented stock is sorted to eliminate soft pickles and bloaters and packed intojars. The
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product is then covered with the original curing brine which is heated to 160170°F (71-77'C). The jar is capped and pasteurized so that product at cold point of container reaches a temperature of 160-170'F (71-77'C), followed by prompt cooling. Genuine Dills These products must be covered with brine from the original fermentation process which should test out about 8 to 10 grains of lactic acid and reach 1720' salometer. Objectionable cloudiness in the original brine can be removed by filtration. Care should be used to remove all bloaters prior to packing. The original brine is then heated to 160-170'F (71-77'C) and poured over the pickles, the jars capped and the sealed containers are ready for pasteurization. A marked improvement in the retention of firmness in genuine dills during storage can be obtained by pasteurizing the cured product in sealed containers so that product at the cold point of the container is heated to 160-170°F(7177'C), followed by prompt cooling.
PICKLED PEPPERS The U.S. pickle industry has had increasing demand in recent years for various types of pickled peppers, especially in food service. Some of the major types and processing steps follow:
Pepperoncini These peppers are imported from the Mediterranean countries, mainly Greece, and are already brined and cured. They are cured with salt, vinegar, other organic acids and very high levels of sulfites. The peppers are desalted to about 6% salt by leaching in water €or at least two days; this also removes much of the sulfites. The peppers are packed into containers and covered with a brine containing about 5% acetic acid. The equalized product should have about 2.5%acetic acid and 3%salt. Sodium benzoate is added as preservative. The jars are capped and cased. Heating is not usually required. Other Whole Pickled Peppers Jalapeno, sweet cherry, and hot cherry peppers are packed in much the same manner as fresh pack dill pickles. The peppers are blanched in hot water at 150-180'F (66-82'C) for three to six minutes, packed intojars, covered with a hot brine containing about 5%acetic acid and 9% salt, capped, pasteurized at 155'F (68'C) and cooled with water sprays. Sodium benzoate preservative is usually added to the brine. Calcium chloride at 0.2% in the brine helps retain texture.
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Sliced Pickle Pepper Rings Jalapeno and hot cherry peppers are sliced into rings 1/&1/4 in. (0.32-0.64 cm) thick. The slices are packed into containers, covered with a hot brine containing about 5%acetic acid, 910% salt, 0.2% calcium chloride, and sodium benzoate, and capped. Thejars are pasteurized to 155'F (68'C) for ten minutes, and cooled with water sprays. Banana pepper slices are not usually pasteurized, due to loss of texture from heating. Preservation is accomplishedby salt (about 5%) acetic acid (about 3%)in the equalized product and chemical preservatives, covering the slices with a hot brine, 140-160°F(60-71"C),before capping. This process inactivates much of the softening enzymes naturally in the peppers.
CANNING OF PICKLES
(SWEET,SOUR AND DILL) About 99% of pickles and pickle products are packed in glass. No. 10 cans are, however, used for government packs, and for some institutional trade. Smaller sizes of cans may, of course, be used if desired. Heavily lacquered cans are used. A can manufacturer should be consulted. Pickles for institutional use are packed in 2-5 gal. (7.619 L)plastic pails and in flexible pouches of various sizes. Canning Procedure
m s t Methd - Pickles are packed into cans and the proper brine added (sweet brine for sweet pickles, vinegar for sour pickles, and dill liquor together with a little dill weed for dills). The liquor may be added cold and the cans passed through an exhaust box giving a sufficiently long exhaust to obtain a temperature of 165-170'F (7477'C) in the product at the center of the cans as they come from the exhaust box; the liquor may be added hot and the cans exhausted afterwards,in which case a shorter exhaust may be used than if cold liquor is added. Steam exhaust boxes are generally used; the time of exhaust generally necessary for No. 10 cans is 8 to 9 minutes. Water exhaust boxes may be used, if desired, but are not as satisfactory as steam exhaust boxes. After exhausting, all the cans pass immediatelyto the closing machine, and after closing they should be cooled in cold water to 100'F (38'C) or lower, (insufficient cooling results in soft pickles) before casing. Cans should not be cased while they are still wet. - Pickles are packed into cans as in the previous method and the proper brine added. The best practice in order to secure the proper vacuum is to heat the brine to 180-190'F (82-88'C) before filling into cans.
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The cans are then dosed on a vacuum closing machine at a vacuum of 14 to
16 in. (38-40 cm) for No. 10 cans, or at as high vacuum as can be obtained without paneling the sides of the cans.Smaller size cans should be sealed at 20 to 22 in. (51-56 cm) vacuum.
The closed cans should either be given a spray of warm water to remove the brine from the outside or should be wiped with a cloth. Cans of pickles should be stored in a relatively cool place and the best practice is not to pack large quantities in cans for long storage, but only to pack on orders or in such quantities as to take care of orders expected in the near future. ACKNOWLEDGEMENTS The author wishes to acknowledge the contributions to this chapter made by Dr. Henry P. Fleming, ARS, U.S. Department of Agriculture, and Department of Food Science, North Carolina State University, Raleigh; and James B.Joiner, Quality Manager, W.B. Roddenbery Co., Inc., Cairo, GA.