SNACK FOODS | Dietary Importance

5332 SNACK FOODS/Dietary Importance

Further Reading

Dietary Importance

Anonymous (1996) Healthy starch innovations for snacks and cereals. Food Technology Europe 3: 46. Arya SS (1991) Grain based snack and convenience foods. Indian Miller 21: 6. Booth RG (ed.) (1990) Snack Food. New York: Van Nostrand Reinhold. Burge RM and Duensing WJ (1989) Processing and dietary fibre ingredient application of corn bran. Cereal Foods World 34: 535. Chauhan SK, Joshi VK and Lal BB (1993) Apricot-soy fruit bar: a new protein enriched product. Journal of Food Science and Technology 30: 457. Crocombe BI (1988) The development and production of jerky at Mirinz’s meat products line. Bulletin of the Meat Industry Research Institute of New Zealand 855: 126. Frame ND (ed.) The Technology of Extrusion Cooking. New York: Blackie Academic and Professional. Friesen SA (1995) Heat Expanded Whole Kernel Snack Food. United States patent. Gomez MH, Rooney LW and Waniska RD (1987) Dry corn masa flours for tortilla and snack food production. Cereal Foods World 35: 372. Gould WA (1985) Changes and trends in snack food industry. Cereal Foods World 30: 219. Howlett RJ (1993) Bagged Snacks. UK patent application. Huang DP (1995) New perspectives on starch and starch derivatives for snack application. Cereal Foods World 40: 528. Jomduang S, Mohamad S, Muhammand K and Abu-Bakar A (1995) Extending shelf life of ‘Khao Kriap Wane’ – a traditional Thai glutinous rice-based snack. Journal of Science and Food Agriculture 67: 29. Kano I (1993) A growing chimni market in Japan. Infofish International 4: 18. Lasekan OO, Lasekan W, Idown MA and Oja OA (1996) Effect of extrusion conditions on the nutritional value, storage stability and sensory characteristics of a maize-based snack food. Journal of Cereal Science 24: 79. Madonna MD (1983) Pretzels as low calorie snacks. Cereal Foods World 28: 297. Matz SA (1976) Snack Food Technology. Westport, Ct: AVI Publishing. Midson K (1999) Indian ethnic snacks. Processed Food Industry 3: 38. Robert BA and Burkes AL (1989) Crisp Fruit or Vegetable Snack Products and Process. United States patent. Sheng DY (1995) Rice-based ingredients in cereals and snacks. Cereal Foods of the World 40: 538. Slige MR (1983) Fruit and nut ingredients. Cereal Foods of the World 25: 286. Stauffer CE (1983) Corn-based snacks. Cereal Foods World 28: 301. Stauffer CE (1983) Corn masa. Baking and Snack. October: 35. Tettweiler P (1991) Snack foods worldwide. Food Technology 45: 58.

A S Bawa and J S Sidhu, Guru Nanak Dev University, Amritsar, India Copyright 2003, Elsevier Science Ltd. All Rights Reserved.

Background This article deals with the dietary importance of processed snack foods with a passing reference to fruits and fruit bars. However, these as well as fruit juices may be included under the term ‘snack foods.’ In general, snack foods are considered as ‘junk foods’ or ‘empty calories.’ Our diet is generally based upon three principal meals a day, and the role of snack foods is to offer a light, convenient, and enjoyable food option, when, for reasons of hunger or sociability, a food selection is required at a time between that allotted for principal meals. Thus, snack foods are not designed to be alternatives for three main meals a day. They are convenient to eat, involving no preparation time or effort by the consumer. Snacks are eaten not only to satisfy hunger or supply the nutrients to our body, but also for social reasons. On many occasions, the inclusion of snack foods in our diet is not justified in terms of nutritional demands. The nutritional value of different snack foods, extent and frequency of consumption by different people, and the need for fortification have been discussed. Snack items and processed foods are presumed to have a high sodium content, and this should be avoided. Teenage boys are most likely to have a low intake level of calcium, iron, magnesium, and vitamin B6, and teenage girls consume these nutrients at still lower levels. The food items most frequently consumed by both sexes between meals are cakes, cookies, pies, candy, and desserts. The most popular foods are salted snack foods, such as chips (crisps), pretzels, and popcorn. Males incorporate more breads, wafers, and other bread products into their snacks than females, whereas females eat more snacks containing condiments, fat spreads, and dips than do males. (See Calcium: Physiology; Iron: Physiology; Magnesium; Sodium: Physiology; Vitamin B6: Properties and Determination.) The real nutritional concerns about snack foods center on the sodium, energy, vitamin, mineral, and dietary fiber contents.

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Nutritional Value of Different Types of Snack Food Potato Chips (Crisps)

Nutritionally, 28 g (1 oz.) of potato chips provide 647 kJ (154 kcal), contributed by 2 g of protein, 14 g

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SNACK FOODS/Dietary Importance

of carbohydrates, and 10 g of fat. A portion of potato chips (25 g) contains 8% of the recommended daily allowance of vitamin C, 3% of thiamin, 11% of nicotinic acid, 8% of iron, 11% of vitamin B6, 4% of phosphorus and 4% of magnesium. Potatoes are also an important source of dietary fiber. Refer to individual nutrients. Cookies and Crackers 0005

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The principal ingredient in cookies and crackers is unbleached, soft wheat flour, and most of the nutrients in these products are derived from the flour. It can range from more than 90% for saltines and similar products to less than 25% in products such as enrobed wafers. The soft wheat flour used in cookies and crackers contains 8–10% protein, with the higherprotein flours generally being used for crackers and the lower-protein flours for more tender sweet goods. With certain exceptions, the quality does not deteriorate on baking. Most cookies and crackers are made from enriched flour. The main component present in flour is carbohydrate, which is a good source of energy. (See Flour: Dietary Importance.) Other ingredients added to cookies and crackers influence the nutrient content of products either by their own nutritional composition or by diluting the nutrients contributed by enriched flour: for example, sugar contributes energy and carbohydrates; shortening contributes fat, essential fatty acids, and energy; salt contributes sodium; leavening agents contribute sodium, potassium, calcium, and phosphorus; peanut contributes fat and nicotinic acid; fruits and vegetables contribute vitamins A and C, fiber, and minerals; chocolate contributes iron and fiber; and other grains contribute minerals, fiber, and other nutrients similar to wheat flour. The potassium content of cookies and crackers is 25–200 mg and 30–80 mg per 28 g (1 oz.), respectively. During baking and storage, the main nutrients lost are thiamin and vitamin C. Lysine reacts with reducing sugars and becomes unavailable, especially at a high pH. Plain and sandwich cookies have similar nutrients. However, nut-containing cookies provide comparatively more protein, vitamins (such as nicotinic acid), and minerals. (Refer to individual nutrients.) Pretzels

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The average energy content of a 28-g of serving pretzels is 462 kJ. One pretzel rod contains 231 kJ; one Dutch-style pretzel contains 460 kJ, and a handful of twisted, three-ring pretzels contain approximately 419 kJ. Pretzels are low in energy and fat, and have no sugar, but contain a large amount of sodium. The average amount is 450–700 mg of sodium per 28-g serving of pretzels. However, low-salt pretzels,

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containing 300 mg per 28-g serving, and unsalted pretzels are also available for sodium-conscious consumers. The typical ingredients of pretzels are flour, water, yeast, soda, and salt. The flour is from soft wheat with a protein content of 8.50–9.50% and an ash content of 0.40–0.50%. A 28-g serving of pretzels offers approximately 3 g of protein, 23 g of carbohydrates, and 1 g of fat. Pretzels also provide several vitamins and minerals, including thiamin, riboflavin, nicotinic acid, iron, magnesium, and copper. Although the quantities of these nutrients are moderate, the nutritional value of pretzels is significant, since they contain no chemical additives or preservatives. However, some pretzels also offer calcium, phosphorus, and other nutrients in significant amounts. (Refer to individual nutrients.)

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Corn Snacks

Corn snacks are accused of being junk food and without nutrient content. Flour tortillas are low in moisture and high in fat, protein, and carbohydrates, compared to corn tortillas. The energy content is, on average, 25% higher than that of corn tortillas. The phosphorus and calcium contents in corn tortillas are substantive. The iron content in corn tortillas is similar to that of wheat flour tortillas. Both the flour and corn tortillas are significant sources of zinc; corn tortillas are also a significant dietary source of copper and magnesium. Tortillas contain modest amounts of sodium and potassium, but because of the significant losses during processing, they are an insignificant source of thiamin and riboflavin. All tortilla products are substantial sources of nicotinic acid. Tortillas do not contain measurable quantities of vitamin C or b-carotene. Refer to individual nutrients. A fruit bar containing apricot pulp and soy slurry in the ratio 70:30 has been found to be most acceptable in terms of sensory properties. This bar contained 15.3% moisture, 7.8% protein, and 16.5 mg of ascorbic acid per 100 g, and had a good flavor (not beany) and texture. In one study, consumers in Newcastle perceived cereal bars to be healthiest. However, an analysis of seven popular cereal bars revealed that they are only marginally healthier than traditional cereal snacks. The varieties containing chocolate chips were preferred but were not necessarily the healthiest. An assessment of the perception of fruits in relation to manufactured snack foods has revealed that fresh fruit and a canned snack fruit product were both perceived as healthy and refreshing by working women in the UK, manufactured snack foods were considered more convenient and suitable for comfort eating, and bananas and apples were

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perceived as more convenient than orange and kiwi fruit. The Nigerian snack foods, robo, kulikuli, and kokoro, prepared from watermelon seeds, groundnut, or maize kernels, have 23.4–42.0% fat and only 1.5–7.3% moisture, and a maximum shelf-life of about 150 days at 30–31  C. An extruded snack prepared from a blend of tapioca, wheat flour, maize grits, spirulina, etc. is quite nutritious and contains: energy 411 kcal, protein 8.7 g, fat 7.6 g, carbohydrates 77.2 g, Ca 68.0 mg, Fe 2.8 mg, vitamin A less than 3 IU, thaimin 0.1 mg, riboflavin 0.2 mg and vitamin C less than 0.35 mg per 100 g. It is low in fat and relatively high in Ca and Fe, compared to other similar snacks. Overall, corn snacks can contribute positively to the diet by providing certain nutrients and minerals necessary for nutritional balance and they have a good flavor and a pleasing texture. In potato chips and nuts, the salt is on the surface of the foods, so the immediate taste perception is of saltiness – much more so than if the salt were uniformly distributed, as in most other foods. Many snack foods contain moderate to high amounts of salt on a percentage basis. The average serving of snack foods is much less than 100 g, ranging up to 40 g and averaging about 35 g; in comparison, many sodiumcontaining staple foods are eaten in quantities greater than 100 g. It is more sensible to examine the sodium content of snack foods on a per-serving basis (Table 1) because the sodium content of snack foods is much lower than that of certain commonly consumed foods, such as bread and butter, sandwiches, and

other foods at the bottom of the table. The sodium content of a packet of chips, for example, is less than that of a plain sandwich, and over six packets of salted chips would have to be consumed to obtain the same amount of sodium contained in a single hamburger. The second aspect of concern is the energy content of snack foods. It is generally believed that snack foods are both rich in energy and fattening, since they are cooked in, or blended with, oil. A comparison of energy content of foods on a per-serving basis (Table 2) shows that the consumption of lightly cooked vegetables instead of snacks can reduce the energy intake and that the energy content of snacks is not as high as is popularly perceived, since hot dogs and hamburgers have much higher energy contents. A packet of chips does not contain much more energy than a cup of milk or a plain yogurt, and somewhat less than a bread-and-butter sandwich. It is much more difficult to control the energy and fat content of snack foods than it is to control sodium content. The technology to produce fat-reduced potato chips does not exist, but the level of fat can be controlled by careful regulation of cooking parameters. Oil is essential in cereal snacks to give an acceptable mouthfeel, and with nuts, the oil is already present before cooking. The only way to control the energy consumption via snack foods is to reduce the size of the serving; Table 3 shows gives the effect of serving size on energy content. The vitamin and mineral contents of snack foods are another area of concern; Table 4 lists the vitamin and mineral contents of some selected snack foods.

Table 1 Sodium content of some foods

Table 2 Energy content of some foods

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Food

Sodium content (mg per serving)

Food

Energy content (kJ) per serving

Most fresh fruits and vegetables Eggs (one medium) Rump steak (130 g) Fried chicken leg Whole milk (1 cup, 237 ml) Salted peanuts (25 g) Toasted CCS (25-g packet) Salted chips (25-g packet) Flavored chip crisp sticks (25-g packet) Flavored chips (25-g packet) Bread-and-butter sandwich Cheese Twisties (25-g packet) Scrambled egg Fritz or Devon (two slices) Hot dog Hamburger

Negligible 54 121 122 128 197 220 234 280 306 367 440 534 650 1102 1591

Lettuce Peas Boiled egg (one medium) Baked fish (one fillet) Salted peanuts (25 g) Whole milk (1 cup, 237 ml) Plain yogurt (1 cup, 237 ml) Potato chips (25-g packet) Twisties (25-g packet) Chip crisp sticks (25-g packet) Bread-and-butter sandwich Hamburger patty Flavored and fruit yogurt (1 cup, 237 ml) Fish, buttered and fried (one fillet) Hot dog Grilled steak (130 g)

17 163 301 326 584 644 690 739 810 814 865 932 982 1041 1342 1822

Data from Delroy B (1985) The role of snack foods. Food Technology in Australia 37(4): 154–158.

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a 4.2 kJ is equivalent to 1 kcal. Data from Delroy B (1985) The role of snack foods. Food Technology in Australia 37(4): 154–158.

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The potassium content of chips is higher than sodium in spite of the added salt, and this is significant in view of the criticism that high sodium levels in processed foods are associated with depleted potassium levels. However, since snack foods are designed to be occasional between meal snacks, their contribution to the diet may be of little significance to the average person. Cereal snacks can be fortified with added vitamins and minerals to any desired level, but it is not common practice, since snack foods are not considered to be suppliers of significant quantities of minerals and vitamins. (See Food Fortification.) The importance of dietary fiber in snack foods is still not very clear, partly because of problems with analytical methods; Table 5 compares the dietary fiber content of snack foods with that of a bread sandwich. The figures indicate that the four snack foods contain more dietary fiber than a white-bread sandwich, and chip crisp sticks more than a brownbread sandwich. Since bread is one of our best sources of dietary fiber, and the cereals and root vegetables from which snacks are developed are sources of the highest-quality fiber, snack foods cannot be rejected on the basis of their fiber content. Snack foods are neither an important source of micronutrients nor simply ‘empty calories.’ Snack foods prepared from whole cereal grains can be a good source of dietary fiber, and the addition of a few per cent of bran in place of the purified cereal fractions improves the fiber content of the finished products. Dairy and meat products have negligible fiber contents, and potatoes

Table 3 Effect of serving on energy content Food

Small apple Twisties (15-g packet) Salted chips (20-g packet) Milk (1 cup, 237 ml) Bread-and-butter sandwich

Energy (kJ) per Fat (g) Sodium (mg) serving 222.0 460.0 565.0 644.0 865.0

0.3 5.9 8.8 8.7 8.6

Negligible 250.0 179.0 128.0 267.0

Data from Delroy B (1985) The role of snack foods. Food Technology in Australia 37(4): 154–158.

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are rather low in this component. (See Dietary Fiber: Physiological Effects; Effects of Fiber on Absorption.)

Levels of Snack Foods Eaten The results of various previous studies (Table 6) reveal that children and teenagers have at least one snack during the day. Adults tend to snack less frequently, and the percentage of adults who ‘snack’ decreases with age. Snacks provide at least 20% of energy for those who eat at least one snack a day and account for 12% of the average protein intake, 16% of the fat intake, and 25% of the daily carbohydrate intake. ‘Snackers’ obtain, on average, 14% of their daily iron intake, 18% of their phosphorus intake, 21% of their magnesium and calcium intakes, 13–14% of their vitamin A, thiamin, preformed nicotinic acid, vitamin B6, and vitamin B12 intakes, and 16–17% of their vitamin C and riboflavin intakes. As the number of snacks eaten increases, the amounts of nearly all nutrients and energy also increase. An increased level of snacking makes a significant contribution to children’s intake levels of magnesium and zinc, and to adolescents’ intake of vitamin B6, calcium, iron, magnesium, and zinc. On days when no snacks are eaten, the intake of fat, sugar, and sodium is decreased, and more food is eaten during the main meals. Snacking has little impact on the nutritional quality of the diet of elderly individuals. Crisps are the most popular snack among 7–8-year-old children in Scotland and are eaten by 92% of the children. Snacks contribute 26% of energy intake and a large proportion of macronutrient intakes. Low and high snacking habits have no significant effect on the anthropometry of children. (Refer to individual nutrients.) Children aged 9–13 years eat dessert items between meals followed, in descending order of frequency, by fruit and milk. The snacks most frequently eaten by 3–5-year-olds, in descending order of frequency, are bakery products, milk, soft drinks, fruit, mild desserts, candy, and bread. For 6–11-year-olds, the snacks in order of importance are bakery products, soft drinks, milk, milk desserts, candy, fruit, salty snacks,

Table 4 Vitamins and minerals in snack foods Snack food

Vitamin B1 (mg)

Nicotinic acid (mg)

Vitamin C (mg)

Calcium (mg)

Iron (mg)

Potassium (mg)

Potato chips (25-g packet) Twisties (25-g packet) Chip crisp sticks (25-g packet) Peanuts (25 g)

37.0 (3%) 7.0 (1%) 78.0 (7%)

1.2 (11%) 0.2 (2%) 0.5 (4%)

2.4 (8%) 0.0 0.0

8.5 (1%) 44.0 (6%) 46.0 (7%) 8.0 (1%)

0.8 (8%) 0.1 (1%) 0.9 (9%) 0.3 (3%)

445.0 70.0 64.0 135.0

Figures in parentheses are the percentage of the recommended dietary allowance, as defined in the NH and MRC Food Legislation (1983). Data from Delroy B (1985) The role of snack foods. Food Technology in Australia 37(4): 154–158.

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Table 5 Dietary fiber in various snack foods Snack

Insoluble dietary fiber (gram per serving)

White-bread sandwich Brown-bread sandwich Wholemeal-bread sandwich Twisties (25-g packet) Potato chips (25-g packet) Chip crisp sticks (25-g packet) Peanuts (25 g)

0.2 1.4 3.1 0.3 0.6 1.5 1.6

Data from Delroy B (1985) The role of snack foods. Food Technology in Australia 37(4): 154–158.

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Table 6 Consumption of nuts and nut mixtures Country

Quantity (kg per capita)

The Netherlands Germany UK France USA Belgium Switzerland Italy

1.28 0.95 0.66 0.65 0.60 0.56 0.18 0.10

Data from Tettweiler P (1990) Snacks ^ Food, Fun and Fashion. Dragocco Report 3, pp. 79 –104. Holzminden, Germany: DRA-GOCCO.

and bread. Among teenage boys, the most popular snacks are soft drinks, milk, bakery products, bread, mild desserts, salty snacks, meats, and fruit, while teenage girls prefer soft drinks, bakery products, milk desserts, salty snacks, fruit, milk, candy, bread, and meat. Among adolescents, the preference for snack foods is bakery products, milk, fruit and fruit juices, milk desserts, salty snacks, and bread. Table 6 lists the per capita consumption of nuts and nut mixtures. (See Adolescents; Children: Nutritional Requirements.)

Nutritional Improvement of Snack Foods 0022

In order to counter the belief of consumers and nutritionists that snack foods are ‘empty calories,’ a number of manufacturers of snack foods have started the development of products supplemented with vitamins, minerals, or proteins. Vitamin supplementation is somewhat simpler than mineral or protein supplementation. The cost is reasonable; a small fraction of a per cent per portion of a supplement is restricted to five vitamins, but vitamins can affect the flavor, and some can cause off-flavors. Riboflavin is highly colored, but its yellow hue is compatible with many snacks. Storage deterioration of these labeled substances is compensated for by the addition of extra

amounts, so that the consumer should obtain the full claimed quantity. When supplementing with any nutritional factor, the manufacturer must establish a quality-control program that will ensure that every lot contains the claimed amount. Storage loss of minerals is not generally observed, except for iodine. Most snacks are poor sources of protein, and the protein that is present is often of a poor nutritional quality. Protein supplementation is possible by increasing the protein-efficiency ratio of the protein already present, or increasing the total amount of protein present by adding some purified nitrogenous material, such as casein, isolated soya protein, or egg white. Untreated corn is a staple food in South America, and there is a need to develop more nutritious, corn-based snack foods. These foods could serve as vehicles for nutrients while at the same time being readily accepted by the population. Certain combinations of cereals and legumes are very desirable from a nutritional point of view. Legumes are a better source of lysine and total protein than cereals, and the latter are a better source of sulfur amino acids. Many attempts have been made to raise the protein value of tortillas by combination with legumes. Snack foods are generally preferred by children and teenagers; in these stages of life, the amount and nutritional quality of proteins are important because of their essential function in physical and mental development. Baked snack foods containing high levels of fiber and fat can be produced using specialty (100% fat-free) starches, e.g., Novelose. Fried snack formulations containing carboxymethyl cellulose absorb less oil during frying, which is advantageous for low-fat applications. The high snackers have low energy and low macronutrients from meals, so snacks make an important contribution to energy and nutrients, even though a high intake of snacks affects the quality of children’s diets. A high snacking frequency and choosing from a wider variety of snack foods results in a balanced intake of nutrients. An extruded snack food (soyabari snack sticks) based on soybeans and maize (corn) rich in crude fiber and protein contents can be produced by adding different ingredients such as pepper, onion, salt, palm oil, plantain, and banana. This product is acceptable to Nigerians. A high-protein, shelf-stable, expanded extruded snack food resembling bread sticks has been prepared using mechanically recovered poultry meat and wheat. (See Protein: Quality.) Consumption of olestra, a fat replacer in savory snack foods, has been found to be age- and genderdependent, with mean chronic and acute olestra intakes for all ages and both genders of 3.1 and 10.2 g per day.

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A study evaluating the nutrient density of snacks and meals, and the effect of eating frequency on mean daily nutrient intake in female students (aged 17–26) has shown that as the eating frequency increased, the number of snacks and the number of different snack items in the diet increased, while the number of meals remained constant. Snacks had lower nutrient densities than meals for nonstarch polysaccharide, minerals, and vitamins, except vitamin C. Mango bars fortified with desiccated coconut powder or soyprotein concentrate are quite acceptable initially, but storage beyond 90 days lowers their rating, compared to plain mango. A low-calorie, low-cholesterol, shelf-stable expanded snack product can be prepared from raw or mechanically separated, comminuted meat mixed with pregelatinized flour and processed through high-temperature, short-time screw-type cooker extruder. A gun-puffed, extruded snack food, low in fat and high in carbohydrates, prepared by incorporating fruit and vegetable extracts with oat flour, starch, and sugars, is low in fat and high in calories. Substantial efforts have been made to reduce the ‘snacking habit’ of various populations, but snackfood consumption continues to increase. Consequently, there is a tendency to increase the production of more nutritious snacks, including those made from corn. Composite flours using corn, chickpea, soya bean meal, and methionine can be formulated, extruded into snack foods, and fried. These products have higher protein-efficiency ratio values than the controls, while the color, flavor, texture, and overall acceptability remain similar. These products are a good alternative to commercially available snack foods. See also: Adolescents; Calcium: Physiology; Children: Nutritional Requirements; Dietary Fiber: Physiological Effects; Effects of Fiber on Absorption; Flour: Dietary Importance; Food Fortification; Iron: Physiology; Magnesium; Protein: Quality; Sodium: Physiology; Vitamin B6: Properties and Determination

Further Reading Anon (1993) CMC smooths production of extruded snacks, cereals. Prepared Foods 162(10): 81. Anon (1996) Healthy starch innovations for snacks and cereals. Food Tech Europe 3(2): 46. Bednarcyk NE (1987) Nutrient contribution of cookies and crackers. Cereal Foods World 38(5): 367. Chauhan SK, Joshi VK and Lal BB (1993) Apricot–soy fruit bar: a new protein enriched product. Journal of Food Science and Technology 30(6): 457–458.

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Conninghum FE, Neumann PE and Huber GR (1993) Extruded Meat-based Snack Food and Method for Preparing Same. US Patent. Delroy B (1985) The role of snack foods. Food Technology in Australia 37(4): 154–158. Henshaw FO and Ihedioha CN (1992) Shelf life studies on some Nigerian indigenous snackfoods. Nahrung 36(4): 405–407. Jack FR, O’Neill J, Piacentini MG and Schroeder MJA (1997) Perception of fruit as a snack: a comparison with manufactured snack foods. Food Quality and Preference 8(3): 175–182. Madonna MD (1983) Pretzels as low calorie snacks. Cereal Foods World 28(5): 297. Matz SA (1976) Nutritional Supplementation. Snack Food Technology. Westport, CT: AVI. Mir MA and Nirankar N (1993) Storage changes in fortified mango bars. Journal of Food Science and Technology 30(4): 279–282. Mitchell V and Boustani P (1990) Cereal bars. Nutrition and Food Science 127: 20–21. Morgan KJ (1983) The role of snacking in American diet. Cereal Foods World 28(5): 305. Olusola-Omueti and Morton ID (1996) Development by extrusion of soyabari snack sticks; a nutritionally improved soya–maize product based on the Nigerian snack (Kokoro). International Journal of Food Science and Nutrition 47(1): 5. Ranhotra GS (1985) Nutritional profile of corn and flour tortillas. Cereal Foods World 30(10): 703. Ray EE (1994) Method of Preparing Snack Food Products. US Patent. Ruxton CHS, Kirk TR and Belton NR (1996) The contribution of specific dietary patterns to energy intakes in 7–8 year old Scottish school children. Journal of Human Nutrition and Dietetics 9(1): 23–31. Stevens MPA, van Zuilichem DJ and de Waart J (1991) Tapsea-vegetable: Development of a new snack. Voedingsmiddelentechnologie 24(2): 12–14. Tettweiler P (1990) Snacks – Food, Fun and Fashion. Dragocco Report 3, pp. 79–104. Holzminden, Germany: DRA-GOCCO. Warren AB, Hnat DL and Michnowski J (1983) Protein fortification of cookies, crackers, and snack bars: uses and needs. Cereal Foods World 28(8): 441. Webb DR, Harrison GG, Min JL and Mei HH (1997) Estimated consumption and eating frequency of olestra from savoury snacks using menu sensus data. Journal of Nutrition 127: 1547S–1554S. Whybrow S and Kirk TR (1997) Nutrient intake and snacking frequency in female students. Journal of Human Nutrition and Dietetics 10(4): 237–244. Zammer CM (1995) Gun-puffed vegetable snacks: a new way to eat your veggies. Food Technology 49 (10): 64.