interaction of meat and vegetable proteins in extended meat products
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ENZYMATIC HYDROL YSIS OF INULIN AND ITS RELATEDFRUCTOSANS. McKay, e., E. Hoehn and R. Bacchus, Department of Food Science, University of Manitoba, Winnipeg, Manitoba R3T 2N2.
Current research at our department has been directed towardsthe utilization of Jerusalem Artichoke (JA) (Helianthus tuberosus L.)as a source of high fructose syrup. The degradation of inulin both bytuber enzymes and a number of enzymes from other sources wasinvestigated in view of storage of and to application in processing ofJA tubers. Enzyme activities were evaluated based on assaysinvolving measurement of reducing sugars and formation ofoligomers by GLC techniques. Results indicated that tuber enzymeswere relatively heat labile and thus (I) easily controlled during tuberstorage but (2) not utilizable in processing of tubers. Inulindegrading enzymes showed variability in activity depending on thedegree of inulin polymerization. This and other characteristicsindicated that for processing purposes a mixture of several inulasesmay result in most efficient hydrolysis of inulin to high fructosesyrup.
MOLECULAR WEIGHT DISTRIBUTION OF OVOMUCINFROM THINNED EGG WHITE. Miller, S.M., A. Kato and S.Nakai, Department of Food Science, University of British Columbia, Vancouver, British Columbia V6T 2A2.
It was intended to further prove the involvement of ovomucinalone in egg white thinning. Sedimentation equilibrium ultracentrifugation was used for determining the molecular weight distribution(MWD) of a soluble ovomucin separated from blended egg white bygel filtration. The apparent molecular weight offresh ovomucin was5.64 . 106 at pH 6.95 and an ionic strength of O. 13. Ovomucin fromnaturally thinned white showed similar MWD patterns withoutsigns of degradation. Treatment of fresh white with .02% 2mercaptoethanol decreased mol wt,pp to 309,500 and 726,200. Theseresults support the previous finding that J3-elimination of O-glycosidically linked carbohydrates could be a cause of egg whitethinning, but not disulfide linkage splitting.
COMPARISON OF THE DIRECT AND INDIRECT WIDELINE NMR METHODS FOR DETERMINING SOLID FATCONTENT. Mills, B.L. and F.R. van de Voort, Department ofFood Science, University of Guelph, Guelph, Ontario NI G 2W I.
A "direct" method of measuring the solid fat content by wide-lineNMR was compared to the conventional indirect wide-line NMRprocedure. The direct method is based on the combined use of anarrow (1.5 gauss) and a wide (10 gauss) gate to admit resonancesfrom the liquid and liquid plus solid portions of the fat respectively.The results obtained for four different fats using the direct methoddid not differ significantly from those of the indirect method. Sincethe direct method requires additional measurements, is somewhatmore complex theoretically, and inherently has the potential toprovide more variable results due to the weaker additional signalbeing measured at the wide gate, no real advantage could be foundfor its use.
INTERACTION OF MEAT AND VEGETABLE PROTEINS INEXTENDED MEAT PRODUCTS. Morrissey, P.J., M. Enriquez,D. Mayers, Diversified Research Laboratories, Toronto, OntarioM4W 2L3 and J. R. Quinn and D. Wood, Food Research Institute,Agriculture Canada, Ottawa, Ontario K IA OC6.
Varied effects of vegetable protein substitute in a sausage matrixwere examined by monitoring textural attributes. Formulationsprepared using several proteins and an inert material were immersion cooked to several internal temperatures. Physical appearanceand yields were recorded and textural characteristics measured usingthe Instron Compression Tester. Results indicate the larger thereplacement value the greater the effect on texture. Texturalmeasurements were generally found to increase with increasedinternal temperatures at a constant replacement value. Interactionlevels of the proteins are exhibited in the amount of change intextural characteristics.
APPLICATION OF MODIFIED SUPER-SIMPLEX OPTIMIZATION TO FOOD PROCESSING. Nakai, S. and T. Kuwata,Department of Food Science, University of British Columbia,Vancouver, British Columbia V6T 2A2.
170 {Affaires de I'Institut
A computing program for optimizing 2-5 factor experiments waswritten for a Monroe 1880 calculator. The program includes theweighted centroid method of Ryan (1980) for calculating thereflection conditions. For new processes, it is recommended toperform fractional factorial designs to select influential factorsbefore applying the optimization technique. The optimization canbe flexible using stepwise multiple regression analyses for discardingnonsignificant factors or introducing new factors during optimization procedure. It was found that the method was quite efficient foroptimizing food analysis and processing. Conversely, it was difficultto optimize them without using similar techniques especially whenfactors were interacting.
A NOVEL, MULTI-SAMPLE, TANGENTIAL ABRASIVE DEHULLING DEVICE (TA DD). Oomah, B.D., R.D. Reichert ande.G. Youngs, Food Research Institute, Agriculture Canada,Ottawa, Ontario KIA OC6.
The design and testing of a novel, laboratory tangential abrasivedehulling device (TADD) is described. The unit can process eight 10g samples at a time to provide a measure of grain hardness and anextraction rate based on flour colour. Using barley and grainsorghum as test materials, coefficients of variation range from 1.0 to3.8 for the percent kernel removed at a given time. For thirty-onesamples of sorghum the abrasive hardness index ranged from 5.0 to12.7 and extraction rates from 71 to 98%. One operator can processsixteen samples in duplicate per day.
EXTRUSION CRYSTALLINITY AND ITS EFFECT ONENZYME DIGESTIBILITY. Owusu-Ansah, J., F.R. van de Voortand D.W. Stanley, Department of Food Science, University ofGuelph, Guelph, Ontario NI G 2W I.
The use of extruders in cereal processing, especially in theproduction of precooked and modified starches, ready-to-eatcereals, infant formulae and snack foods, has increased in the lastfew years. However, the formation of extrusion crystallinity inextruded cereals is currently raising much concern with regard to thepossible undesirable effects of this change in products such as infantformulae.
The effect of primary extrusion variables, temperature, feedmoisture and screw speed on extrusion crystallinity in corn starchwas studied using response surface methodology. Extrusion crystallinity was quadratically related to these variables, accounting for84.5% (P<O.OI) of the total variation. The crystallinity decreasedwith increasing feed moisture and decreasing temperature. At higherscrew speeds, higher temperatures were necessary for the formationof crystallinity, but became less important at lower screw speeds.Increases in extrusion crystallinity correspondingly decreased the Ci
amylase susceptibility and the overall digestibility of the extrudates.
LIGHT TRANSMISSION BY BUTTER WRAPPERS ANDOXIDATION. Paquette, G.J., D.B. Emmons, D.e. Beckett, D.A.Froehlich and H.W. Modler, Food Research Institute; G. Butler,Engineering Station Research Service, and P. Brackenridge and G.Henne, Dairy, Fruit and Vegetable Division, Agriculture Canada,Ottawa, Ontario KIA OC6.
An industry-government committee evaluated eleven wrappersfor protecting butter from light-induced oxidation. A survey ofbutter in eight Ottawa stores revealed light-loads up to 5,400 Ix; it wasarbitrarily decided that wrappers should protect butter for 48 h at5°C from 2,000 Ix of Cool-White fluorescent light. Peroxides on thesurface and in the interior of butter were measured; a difference of1.0 meq{ kg or more was considered unacceptable. Light transmission of wrappers ranged from 90% to O. Some wrappers absorbedlight preferentially at <500 nm, others uniformly from 300 to 700nm. Expectedly, aluminum foil yielded no surface oxidation; twometallized parchments and black polyethylene yielded slight surfaceoxidation. Other parchments and yellow-tinted plastics wereunsatisfactory.
AN IMPROVED PROCEDURE FOR THE ISOLATION OFCAMPYLOBACTER FROM FOODS. Park, e.E. and Z.K.Stankiewicz, Microbiology Research Division, Bureau of MicrobialHazards, Food Directorate, Health Protection Branch, Health andWelfare Canada, Ottawa, Ontario KIA OL2.
A sensitive system recovering 100 cells{ kg in the presence of 106•
J. InS!. Can. So'. Technol. Aliment. Vol. 14. No. 3. Juillet 1981