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Chemical Changes Occurring in Carotenoids During Food Processing
do not belong to the major group of mycotoxins known as aflatoxins, sterigmatocystin, ochratoxin A, citrinin, penicillic acid, patulin and zearalenone. Partial purification by ultrafiltration membranes has shown that the component(s) have a molecular weight between 1,000 and 5,000 d. The inhibitory effect has also been shown to be present in whole unprocessed rapeseed. DERANCIDIFICATlON OF MILK BY ACTIVATED CARBON ADSORPTION. Nakai, S., K.P.Y. Cheung and L.P. Voutsinas, Department of Food Science, University of British Columbia, Vancouver, British Columbia V6T 2A2. Activated carbon was used for adsorbing fatty acids from hydrolytically rancid milk. A 2 x 40 cm jacketed column was packed with 40 g of granular carbon, Calgon type CPG, and 400 mL of milk was pumped through the column at 60°C at a flow rate of 1.3 mL/min. The acid degree value of milk decreased from 2.6-1.1 without a sign of declining adsorptivity. The treated milk was whiter and blander than untreated milk. The temperature and flow rate were critical for the derancidification efficiency. Granular carbon was definitely advantageous over powdered carbon due to less leakage of carbon into the treated milk. PROTEASE ACTIVITY IN FIG CELL SUSPENSION CULTURES. Nilsson, E.K. and P.M. Townsley, Department of Food Science, University of British Columbia, Vancouver, British Columbia V6T 2A2. Commercial ficin preparations are currently obtained from latex of immature figs, Ficus carica. This investigation was conducted to determine the feasibility of enzyme production in vitro. Standard methods of leaf tissue excision were employed for callus development, and cell suspension cultures started from callus were maintained at 28°C in darkness. Proteolytic activity, as determined by a modification of the Food Chemicals Codex method for papain, was variable among cell lines over a 4 week period. Numerous medium supplements were assessed for possible stimulatory effects. Nitrate at 5-25 mM was crucial for good growth. Three percent skimmed milk, or the fresh casein and whey fractions thereof, all doubled enzyme activity. Some improvement was also evident using lactose, citrate and casein hydrolysate. Thiol reagents, though required for enzyme activation during assay, had no effect when added to the growth medium. CHEMICAL CHANGES OCCURRING IN CAROTENOIDS DURING FOOD PROCESSING. Onyewu, P.N. and H. Daun, Department of Food Science, Rutgers University, New Brunswick, New Jersey 08903. Carotenoids are one of the most widespread minor components of food. This unique group of substances contributes to colour, nutritive value and flavour of many food products. During processing and storage, carotenoids undergo isomerization, cyclization, oxidation and other reactions. Several low molecular volatile degradation products of carotenoids have been reported, while little is known on the nonvolatiles. ABRASIVE TYPE DEHULLING OF GRAIN LEGUMES. Oomah, B.O., R.D. Reichert and e.G. Youngs, Prairie Regional Laboratory, National Research Council of Canada, Saskatoon, Saskatchewan S7N OW9. An abrasive type batch dehuller (4-7 kg), suitable for dehulling grain legumes, was built and tested. Resinoid disks or a combination of resinoid disks and carborundum stones mounted on a horizontal shaft provide the abrasive action. Soybeans, fababeans, mung beans, field peas, kidney beans, lentils and cowpeas were effectively dehulled at extraction rates of 74-87%. Dehulling efficiency, which expresses the proportion of actual hull material in the bran fraction, was developed to rank the performance of the legumes in the machine. Soybean dehulling was most efficient (DE = 0.72), while brown cowpeas was least efficient (DE = 0.1 I). OXIDATION OF BUTTER AT LOW INTENSITlES OF FLUORESCENT LIGHTS. Paquette, G.J., D.B. Emmons, D.A. Froehlich and D.C. Beckett, Food Research Institute, Research Branch, Agriculture Canada, Ottawa, Ontario KIA OC6. A previous experiment showed that nine wrappers, except aluminium foil, allowed oxidized flavour to develop even at 400 Ixll day. To assist in developing transmission standards for wrappers, butter was exposed under Saran to levels of light ranging from 50-400 Ix/2 days. An expert panel detected very slight oxidized flavour even at the lowest intensity, equivalent to 2.5% transmission of a previously selected Can. Inst. Food Sci. Ttchnol. J. VoJ. IS, No. 3, 1982
standard of 2,000 Ix/2 days. It was concluded that very little exposure to fluorescent lights results in detection of oxidized flavour on the surface of butter. Peroxide values, percentage detection of oxidized flavour and percentage downgrading were closely correlated. QUALITY OF PRINTED BUTTER DURING FROZEN STORAGE. Paquette, G.J., D.B. Emmons, D.A. Froehlich and D.e. Beckett, Food Research Institute, Research Branch, Agriculture Canada, Ottawa, Ontario KIA OC6. Butter from each of two factories was stored for 12 mo at -21°C in ten different wrappers. The butter remained first grade in the interior and on the surface for the 12 mo with most wrappers. There was no evidence of serious oxidation on the surface with any wrappers as evidenced by increased peroxide values or by description of offflavours as oxidized by an expert panel. Three wrappers, in particular two prototype aluminized parchments, had off-flavour described variously as, cardboard, box, paper or wrapper. One of the aluminized parchments also discoloured during storage, with patches becoming transparent and showing the yellow colour of the butter. In this experiment frozen storage of high quality butter for I year resulted in a high quality product. COMPARISON OF FIVE DIFFERENT SELECTIVE PLATING MEDIA FOR ISOLATION OF CAMPYWBACTER JEJUNI FROM FRESH WHOLE CHICKENS. Park, C.E. and Z.K. Stankiewicz, Microbiology Research Division, Bureau of Microbial Hazards, Food Directorate, Health Protection Branch. Health and Welfare Canada, Ottawa, Ontario KIA OL2. Five selective agar media (Butzler, a modification of Butzler, Skirrow, a modification of Skirrow and Campy-BAP) were compared for the primary isolation of Campylobacler jejuni from naturally contaminated fresh whole chickens. Each of fifty chickens was washed by massaging with brucella broth (250 mL) in a sterile plastic bag. The cells in the washings were concentrated by centrifugation at 16,000 x g for 30 min at 4°C, and the pellet was suspended in 5 mL of brucella broth. Three loopfuls of cell suspension were plated in triplicate on each plate; the plates were incubated at 42°C for 48 h under the gas mixture (5% O2 , 10% CO2 , 85% N2 ). The isolation rate from the five media was: Campy-BAP (66%) > modified Skirrow (62%) > Skirrow (56%) > modified Butzler (50%) > Butzler (48%). THE EFFECT OF SUPPLEMENTARY VITAMINS AND AMINO ACIDS ON THE CLINICAL BIOCHEMISTRY AND FREE AMINO ACIDS IN THE PLASMA OF CHICKS WITH AFLATOXICOSIS. Park, L.E., M.N. Voigt and J. Veltmann, Department of Biochemistry, Memorial University of Newfoundland, St. John's, Newfoundland AIB 3X9. Aflatoxicosis has been observed to induce characteristic plasma free amino acid and clinical biochemistry profiles in broiler chicks. The effects of administering a series of nutritional factors on these blood components and the performance of chicks with aflatoxicosis has been studied and compared in strains of broiler chicks which vary in their susceptibility to aflatoxin. MANUFACTURING OF GHEE UTILIZING SUBSTANDARD, MARKET REJECT MILKS AND WHEY BUTTER AND BUTTER, USING INEXPENSIVE EQUIPMENT. DOMESTIC AND EXPORT MARKET POTENTIAL OF GHEE. Patel, I.R. and D.H. Thompson, Teeswater Creamery, Teeswater, Ontario NOG 2S0. Butteroil, the equivalent of Ghee, is manufactured by very few dairy plants in Canada, using expensive equipment and mostly good quality cream or butter. Substandard or market return milk and substandard butter, as well as whey butter, is often a disposal problem experienced by some dairies. A simple and innovative procedure is suggested to manufacture high quality Ghee. Ghee manufactured by this method is superior in flavour and keeping quality. Such Ghee has fewer oxidative problems than butteroil made using centrifugal separation procedures. An increase in the domestic market use of Ghee, as well as its export potential, is favourable. MODIFIED DICKERSON METHOD TO STUDY TEMPERATURE DEPENDENCE OF THERMAL DIFFUSIVITY OF FOODS. Ramaswamy, H.S. and M.A. Tung, Department of Food Science, University of British Columbia, Vancouver, British Columbia V6T 2A2.
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standard of 2,000 Ix/2 days. It was concluded that very little exposure to fluorescent lights results in detection of oxidized flavour on the surface of butter. Peroxide values, percentage detection of oxidized flavour and percentage downgrading were closely correlated. QUALITY OF PRINTED BUTTER DURING FROZEN STORAGE. Paquette, G.J., D.B. Emmons, D.A. Froehlich and D.e. Beckett, Food Research Institute, Research Branch, Agriculture Canada, Ottawa, Ontario KIA OC6. Butter from each of two factories was stored for 12 mo at -21°C in ten different wrappers. The butter remained first grade in the interior and on the surface for the 12 mo with most wrappers. There was no evidence of serious oxidation on the surface with any wrappers as evidenced by increased peroxide values or by description of offflavours as oxidized by an expert panel. Three wrappers, in particular two prototype aluminized parchments, had off-flavour described variously as, cardboard, box, paper or wrapper. One of the aluminized parchments also discoloured during storage, with patches becoming transparent and showing the yellow colour of the butter. In this experiment frozen storage of high quality butter for I year resulted in a high quality product. COMPARISON OF FIVE DIFFERENT SELECTIVE PLATING MEDIA FOR ISOLATION OF CAMPYWBACTER JEJUNI FROM FRESH WHOLE CHICKENS. Park, C.E. and Z.K. Stankiewicz, Microbiology Research Division, Bureau of Microbial Hazards, Food Directorate, Health Protection Branch. Health and Welfare Canada, Ottawa, Ontario KIA OL2. Five selective agar media (Butzler, a modification of Butzler, Skirrow, a modification of Skirrow and Campy-BAP) were compared for the primary isolation of Campylobacler jejuni from naturally contaminated fresh whole chickens. Each of fifty chickens was washed by massaging with brucella broth (250 mL) in a sterile plastic bag. The cells in the washings were concentrated by centrifugation at 16,000 x g for 30 min at 4°C, and the pellet was suspended in 5 mL of brucella broth. Three loopfuls of cell suspension were plated in triplicate on each plate; the plates were incubated at 42°C for 48 h under the gas mixture (5% O2 , 10% CO2 , 85% N2 ). The isolation rate from the five media was: Campy-BAP (66%) > modified Skirrow (62%) > Skirrow (56%) > modified Butzler (50%) > Butzler (48%). THE EFFECT OF SUPPLEMENTARY VITAMINS AND AMINO ACIDS ON THE CLINICAL BIOCHEMISTRY AND FREE AMINO ACIDS IN THE PLASMA OF CHICKS WITH AFLATOXICOSIS. Park, L.E., M.N. Voigt and J. Veltmann, Department of Biochemistry, Memorial University of Newfoundland, St. John's, Newfoundland AIB 3X9. Aflatoxicosis has been observed to induce characteristic plasma free amino acid and clinical biochemistry profiles in broiler chicks. The effects of administering a series of nutritional factors on these blood components and the performance of chicks with aflatoxicosis has been studied and compared in strains of broiler chicks which vary in their susceptibility to aflatoxin. MANUFACTURING OF GHEE UTILIZING SUBSTANDARD, MARKET REJECT MILKS AND WHEY BUTTER AND BUTTER, USING INEXPENSIVE EQUIPMENT. DOMESTIC AND EXPORT MARKET POTENTIAL OF GHEE. Patel, I.R. and D.H. Thompson, Teeswater Creamery, Teeswater, Ontario NOG 2S0. Butteroil, the equivalent of Ghee, is manufactured by very few dairy plants in Canada, using expensive equipment and mostly good quality cream or butter. Substandard or market return milk and substandard butter, as well as whey butter, is often a disposal problem experienced by some dairies. A simple and innovative procedure is suggested to manufacture high quality Ghee. Ghee manufactured by this method is superior in flavour and keeping quality. Such Ghee has fewer oxidative problems than butteroil made using centrifugal separation procedures. An increase in the domestic market use of Ghee, as well as its export potential, is favourable. MODIFIED DICKERSON METHOD TO STUDY TEMPERATURE DEPENDENCE OF THERMAL DIFFUSIVITY OF FOODS. Ramaswamy, H.S. and M.A. Tung, Department of Food Science, University of British Columbia, Vancouver, British Columbia V6T 2A2.
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