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Quality and Stability of Dill Oil
acidities of I% were obtained. No Pb, Hg or fecal coliforms were detected in the pickled prod ucts and an average total coliform count of 2610/ mL in the brines was observed. Sensory quality evaluation of the pickled products showed no significant difference between treatments. STABILITY OF VICINE AND CONVICINE IN FOOD PRODUCTS. Kim, S.l. and E. Hoehn, Department of Food Science, University of Manitoba, Winnipeg, Manitoba R3T 2N2. Vicine and convicine are considered to be causative agents of favism. Thus, the presence of these glycosides in fababeans is of concern in view of the use of fababean preparations in foods. This study was initiated to assess the stability and fate of these compounds in pure solution and in bread supplemented with fababean flour. Both glycosides in pure solution were stable under neutral or alkaline conditions; however their respective aglycons derived by action of l3-glucosidase or. acid hydrolysis were highly unstable. Studies on bread supplemented with fababean flour revealed that (I) a portion of the glycosides were completely degraded during the fermentation, and (2) association of undegraded glycosides with protein components took place during baking. Thus the risk of favism related to the consumption of fababean supplemented products appears to be reduced byalteration of processing steps favouring degradation of these compounds. SENSORY ANDPHYSICALCHARACTERISTICSOFBREAD SUPPLEMENTED WITH YEAST-WHEY PROTEIN AND TORULA YEAST. Kupranycz, D.8., Gay Lea Foods Co-operative Ltd., Guelph, Ontario NI H 6J6, and E.A. Gullett, Department of Consumer Studies, University of Guelph, Guelph, Ontario NIG 2WI. Sensory and physical characteristics of white and whole wheat breads supplemented with three levels of yeast-whey protein, produced by the fermentation of K.fragilis on a complete whey medium, were studied in comparison to a commercially obtained Torula yeast. Results indicated that supplementation of bread with yeast-whey protein was more beneficial from a flavour and nutritional standpoint whereas Torula yeast behaved more favourably in baking trials, producing less adverse effects on loaf volume, compressibility, colour and staling of crumb. Consumer evaluations of 10% yeast-whey supplemented breads indicated that yeast-whey protein could be used up to levels of 10% replacement of the flour in bread-baking, while maintaining a product which was acceptable to the segment of consumers represented in the study from a sensory standpoint. In general, the effects on bread produced by yeast addition were less pronounced in whole wheat breads than in white breads at equivalent levels of supplementation. SELECTIVE PRECIPITATION OF WHEY PROTEINS WITH FERRIC CHLORIDE. Kuwata, T. and S. Nakai, Department of Food Science, University of British Columbia, Vancouver, British Columbia V6T 2A2. Experimental conditions used were within the following ranges: pH (2.5-5.5), temperature (4°C-55°C), final Fe concentration (3.010 mM) and extent of desalting (electroconductivity 4,5 x 10 2 - 5.1 X 10 3 J,Lmhos). After formation of the insoluble Fe-protein complex, protein components in the supernatant and precipitate were analyzed by polyacrylamide gel electrophoresis. Electrophoretic patterns indicated that at pH 3.0-3.5 and final Fe concentration 4-6 mM, mainly a-lactalbumin and BSA were precipitated and above pH 3.6, 13-lactoglobulin was predominantly precipitated. More 13lactoglobulin precipitated as the temperature decreased from 55° to 4°C. Desalting of whey improved the purity offractionated proteins; however the best pH for selective precipitation was dependent on the electroconductivity of the whey. COMPARATIVE STUDY OF PROTEOLYSIS IN SHORTFINNED (ILLEX ILLECEBROSUSj AND LONG-FINNED (LOLlGO PEALEJ LESUER) SQUID. LeBlanc, E.L. and T.A. Gill, Fisheries Research and Technology Laboratory, Technical University of Nova Scotia, Halifax, Nova Scotia B3J 2X4. Studies of proteolytic enzymes present in muscular tissue are important from physiological, pathological and bromatological viewpoints. Quality of raw and processed fish muscle reportedly is affected by two types of proteases. Under frozen storage conditions, Can. Inst. Food Sd. Technol. J. Vol. 14. No. 3.July 1981
cathepsins are generally associated with myofibrillar degradation while alkaline proteases appear to be the agents responsible for muscle protein degradation evident as textural changes when fish is cooked. However, proteins of squid muscle differ significantly from those of fish muscle and proteolytic enzyme activity is approximately twice as high. Proteolytic autolytic degradation is probably the single most important characteristic relative to the eating quality of squid. Hence this work was undertaken to characterize the catheptic and protease activity of I. illecehrosus and L. pealei. DEVELOPPEMENT ET MISE AU POINT D'UNE METHODE RAPIDE PERMETTANT D'UNIFORMISER LA CUISSON AFIN D'OPTIMISER LA PERIODE DE CONVERSATION DES PRODUITS DE CHARCUTERIE ET DE SALAISON. Leger, P.P., c.L. Vignola and D. Frechette, Cresala-Hygrade La Belle Fermiere Inc., Montreal, Quebec. L'analyse de la destruction de la catalase en fonction de la temperature de cuisson par la methode de Gagnon et coil. (1959) sur les saucisses fumees, le salami, le bologne et le simili-poulet fait I'objet de cette etude. Les mesures du temps de flottaison, de la temperature de cuisson, du temps de cuisson et les enumerations bacteriologiques sont rapportees. Cette etude a montre qu'un temps de flottaison de 600 s indique que les normes bacteriologiques des produits sont respectees. De plus, il fut determine que des periodes de 14 min pour la saucisse fumee, de 6 h pour le salami, de 4 h pour le simili-poulet et de 7 h pour le bologne, sont suffisantes pour affirmer que les produits sont cuits. QUALITY AND STABILITY OF DILL OIL. Logie, J.R. and E. Hoehn, Department of Food Science, University of Manitoba, Winnipeg, Manitoba R3T 2N2, and B.B. Chubey, Research Station, Agriculture Canada, Morden, Manitoba. The objectives of this study were to investigate the stability of dill oil during storage and to determine the effects of contaminating weed volatiles on the oil quality and stability during storage. Pure dill oil samples were steam-distilled from plants harvested at the milk ripeness stage of maturity. Samples were then stored under oxygen at 26°C and changes in composition were monitored by GLC techniques. Important changes were increased concentration of carvone, an oxygenated monoterpene and decreased concentration of the other major dill oil monoterpenes, a-phellandrene and d-limonene. In addition other trace components became more prominent with increased storage time. Addition of traces ot volatile weed contaminants to pure dill oil samples altered the quality and pattern of storage changes. INTERACTION OF PHYTIC ACID WITH PLANT PROTEINS. Martens, R.W. and E.D. Murray, Department of Food Science, University of Manitoba, Winnipeg, Manitoba R3T 2N2. When fababean protein isolates were prepared using different conditions of pH and ionic strength, varying amounts of phytic acid co-precipitated with the proteins. Since all extraction conditions were above pH 5.3 both the phytic acid and the proteins had net negative charges. This situation suggests an electrostatic repulsive state should exist between these two main structures; such a state is not immediately compatible with the co-precipitation phenomenon. Measurement of free calcium ions(using a calcium electrode) during protein extraction showed that as the solubilizing pH was raised from 8.0 to 10.0, the amount of bound calcium increased. Moreover, phytic acid assays showed that protein isolates contained increasing phytic acid over the same pH range. These conditions of high net negative charge on both the proteins and phytic acid with disappearing calcium ion activity suggest an ionic bridging where a ternary complex (protein-calcium-phytic acid) is formed. DEHYDRA TION OF CARROTS: EFFECTS OF PREDRYING TREATMENTS ON MOISTURE TRANSPORT. Mazza, G., Alberta Horticultural Research Center, Brooks, Alberta TOJ OJO. The effect of blanching, sulfiting, starching, freezing, sucrose and sodium chloride dipping before air drying on the rate of moisture movement during carrot cube dehydration was studied. The results, interpreted in terms of existing heat and mass transfer theories combined with physical and thermodynamic considerations, provide experimental and theoretical evidence that factors such as blanching, freezing and sucrose dipping affected moisture transport and product quality.
Institute Affairs/ 169
cathepsins are generally associated with myofibrillar degradation while alkaline proteases appear to be the agents responsible for muscle protein degradation evident as textural changes when fish is cooked. However, proteins of squid muscle differ significantly from those of fish muscle and proteolytic enzyme activity is approximately twice as high. Proteolytic autolytic degradation is probably the single most important characteristic relative to the eating quality of squid. Hence this work was undertaken to characterize the catheptic and protease activity of I. illecehrosus and L. pealei. DEVELOPPEMENT ET MISE AU POINT D'UNE METHODE RAPIDE PERMETTANT D'UNIFORMISER LA CUISSON AFIN D'OPTIMISER LA PERIODE DE CONVERSATION DES PRODUITS DE CHARCUTERIE ET DE SALAISON. Leger, P.P., c.L. Vignola and D. Frechette, Cresala-Hygrade La Belle Fermiere Inc., Montreal, Quebec. L'analyse de la destruction de la catalase en fonction de la temperature de cuisson par la methode de Gagnon et coil. (1959) sur les saucisses fumees, le salami, le bologne et le simili-poulet fait I'objet de cette etude. Les mesures du temps de flottaison, de la temperature de cuisson, du temps de cuisson et les enumerations bacteriologiques sont rapportees. Cette etude a montre qu'un temps de flottaison de 600 s indique que les normes bacteriologiques des produits sont respectees. De plus, il fut determine que des periodes de 14 min pour la saucisse fumee, de 6 h pour le salami, de 4 h pour le simili-poulet et de 7 h pour le bologne, sont suffisantes pour affirmer que les produits sont cuits. QUALITY AND STABILITY OF DILL OIL. Logie, J.R. and E. Hoehn, Department of Food Science, University of Manitoba, Winnipeg, Manitoba R3T 2N2, and B.B. Chubey, Research Station, Agriculture Canada, Morden, Manitoba. The objectives of this study were to investigate the stability of dill oil during storage and to determine the effects of contaminating weed volatiles on the oil quality and stability during storage. Pure dill oil samples were steam-distilled from plants harvested at the milk ripeness stage of maturity. Samples were then stored under oxygen at 26°C and changes in composition were monitored by GLC techniques. Important changes were increased concentration of carvone, an oxygenated monoterpene and decreased concentration of the other major dill oil monoterpenes, a-phellandrene and d-limonene. In addition other trace components became more prominent with increased storage time. Addition of traces ot volatile weed contaminants to pure dill oil samples altered the quality and pattern of storage changes. INTERACTION OF PHYTIC ACID WITH PLANT PROTEINS. Martens, R.W. and E.D. Murray, Department of Food Science, University of Manitoba, Winnipeg, Manitoba R3T 2N2. When fababean protein isolates were prepared using different conditions of pH and ionic strength, varying amounts of phytic acid co-precipitated with the proteins. Since all extraction conditions were above pH 5.3 both the phytic acid and the proteins had net negative charges. This situation suggests an electrostatic repulsive state should exist between these two main structures; such a state is not immediately compatible with the co-precipitation phenomenon. Measurement of free calcium ions(using a calcium electrode) during protein extraction showed that as the solubilizing pH was raised from 8.0 to 10.0, the amount of bound calcium increased. Moreover, phytic acid assays showed that protein isolates contained increasing phytic acid over the same pH range. These conditions of high net negative charge on both the proteins and phytic acid with disappearing calcium ion activity suggest an ionic bridging where a ternary complex (protein-calcium-phytic acid) is formed. DEHYDRA TION OF CARROTS: EFFECTS OF PREDRYING TREATMENTS ON MOISTURE TRANSPORT. Mazza, G., Alberta Horticultural Research Center, Brooks, Alberta TOJ OJO. The effect of blanching, sulfiting, starching, freezing, sucrose and sodium chloride dipping before air drying on the rate of moisture movement during carrot cube dehydration was studied. The results, interpreted in terms of existing heat and mass transfer theories combined with physical and thermodynamic considerations, provide experimental and theoretical evidence that factors such as blanching, freezing and sucrose dipping affected moisture transport and product quality.
Institute Affairs/ 169