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Elemental Analysis of Canadian, American and European Wines by Pixe
ultrafiltration and activated carbon, which removed 65.7% and 29.5% of the original colour, respectively. The resulting light brown syrup was then purified with ion exchange resins. Column chromatography with ion exchange resins was used to hydrolyze, separate and isomerize the purified syrup. A strong cationic resin (H+ form) was used for the hydrolysis, then a cationic resin (CA2+ form) was used for separation of glucose and fructose, and a strong anionic resin (OH- form) for isomerization of the glucose fraction. The fructose content of the total sugars was 60-70% by weight in the resulting syrup. DETERMINATION OF A PHYTOESTROGEN, COUMESTROL, IN ALFALFA SPROUTS. Yada, S.A. and J. Vanderstoep, Department of Food Science, University of British Columbia, Vancouver, British Columbia V6T 2A2. Germinated alfalfa seeds, or "sprouts," were examined for their content of phytoestrogens, particularly coumestrol. The ability of coumestrol to fluoresce upon exposure to UV light was employed as the basis for chromatographic analyses of coumestrol in alfalfa. Visual comparisons of fluorescence intensities between the coumestrol standard and unknown spots on silica gel TLC plates could serve as a means for a rapid, semi-quantitative analysis. The use of reverse phase HPLC to provide a more accurate quantitative analysis was also investigated. The content of coumestrol has been found to increase during germination of other legumes, therefore the effect of various germination conditions on the accumulation of coumestrol in alfalfa sprouts was studied. Light intensity, rinse frequency and germination time were the major conditions examined. EFFECT OF PHYTIC ACID ON RATE OF STARCH DIGESTIBILITY. Yoon, J.J.H., L.U. Thompson and D.J.A. Jenkins, Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S IAS. The effect of phytic acid on rate of starch digestibility was studied in vivo and in vitro. As observed in humans, glycaemic index negatively correlated with phytic acid intakes. In vitro dialysis system involving human saliva at physiological pH and temperature showed that in the presence of phytate (up to 2%), the rate of raw wheat starch digestibility was reduced significantly by 50%. This was reversed by the addition of calcium which is known to complex phytic acid. In vitro digestibility of starch in unleavened bread with added phytate was also decreased, as was observed with raw starch.
Can. Insl. Food Sci. T.chnal. J. Vol. tS. No. 3. 1982
ELEMENTAL ANALYSIS OF CANADIAN, AMERICAN AND EUROPEAN WINES BY PIXE. Zee, J.A., R.E. Simard, I. Szi:ighy and J. Tremblay, Departement de sciences et technologie des aliments and Centre de recherche en nutrition, Universite Laval, Ste-Foy, Quebec GIK 7P4. Quantitative analysis of P, S, Cl, K and Ca in Canadian, American and European wines was performed by an energy dispersive X-ray fluorescence system (PIXE). Red wines had significantly higher P, S and K contents than white wines, but contained less Ca. When the wines from different countries were compared, P, K and Ca contents in all red wines were not significantly different; French red wines contained the lowest S and Cl contents, while American red wines had the highest Cl content. In white wines, Ca contents were similar; the five elements were the highest in American wines and the lowest in Spanish wines. Bordeaux wines were highest in P, Cl, K and Ca contents and Bourgogne, in S content. Also, commercial wines had higher elemental contents than average. Canadian red wines contained the highest P content and above average S, K and Ca values. In red and white Canadian sherries, Cl content was about twofold that in wines and ciders. Canadian ciders had the lowest P, S, Cl and Ca contents, but the highest K content. Differences are probably due to the nature of raw materials and the various fermentation technologies used. MECHANISM OF CAKE FLOUR CHLORINATION. Zellen, W.L. and V.F. Rasper, Department of Food Science, University of Guelph, Guelph, Ontario NIG 2Wl. Modification of wheat flour for cake production by chlorination has been used for many decades. The mechanism of this treatment is, however, still poorly understood. Rheological tests (alveography, extensigraphy) performed on a series of flours treated with different amounts of Ch have indicated effects on the rheological parameters similar to those resulting from the presence of fast acting oxidizing agents (potassium iodate, azodicarbonamide). The ultimate baking properties of flours treated with these agents were not found to be comparable with those of the chlorinated ones. More recent studies suggested a possible involvement of the lipoxygenase-linoleic acid system in the chlorination mechanism. The above system is known to enhance the gel forming power of gelatinized starch. Results on flours with different degree of chlorination support the lipoxygenase-Iinoleic acid hypothesis, as a highly significant correlation was found between the degree of chlorination on one hand and both gel strength and gel thermal stability on the other.
Institute Affairs / xxiii
Can. Insl. Food Sci. T.chnal. J. Vol. tS. No. 3. 1982
ELEMENTAL ANALYSIS OF CANADIAN, AMERICAN AND EUROPEAN WINES BY PIXE. Zee, J.A., R.E. Simard, I. Szi:ighy and J. Tremblay, Departement de sciences et technologie des aliments and Centre de recherche en nutrition, Universite Laval, Ste-Foy, Quebec GIK 7P4. Quantitative analysis of P, S, Cl, K and Ca in Canadian, American and European wines was performed by an energy dispersive X-ray fluorescence system (PIXE). Red wines had significantly higher P, S and K contents than white wines, but contained less Ca. When the wines from different countries were compared, P, K and Ca contents in all red wines were not significantly different; French red wines contained the lowest S and Cl contents, while American red wines had the highest Cl content. In white wines, Ca contents were similar; the five elements were the highest in American wines and the lowest in Spanish wines. Bordeaux wines were highest in P, Cl, K and Ca contents and Bourgogne, in S content. Also, commercial wines had higher elemental contents than average. Canadian red wines contained the highest P content and above average S, K and Ca values. In red and white Canadian sherries, Cl content was about twofold that in wines and ciders. Canadian ciders had the lowest P, S, Cl and Ca contents, but the highest K content. Differences are probably due to the nature of raw materials and the various fermentation technologies used. MECHANISM OF CAKE FLOUR CHLORINATION. Zellen, W.L. and V.F. Rasper, Department of Food Science, University of Guelph, Guelph, Ontario NIG 2Wl. Modification of wheat flour for cake production by chlorination has been used for many decades. The mechanism of this treatment is, however, still poorly understood. Rheological tests (alveography, extensigraphy) performed on a series of flours treated with different amounts of Ch have indicated effects on the rheological parameters similar to those resulting from the presence of fast acting oxidizing agents (potassium iodate, azodicarbonamide). The ultimate baking properties of flours treated with these agents were not found to be comparable with those of the chlorinated ones. More recent studies suggested a possible involvement of the lipoxygenase-linoleic acid system in the chlorination mechanism. The above system is known to enhance the gel forming power of gelatinized starch. Results on flours with different degree of chlorination support the lipoxygenase-Iinoleic acid hypothesis, as a highly significant correlation was found between the degree of chlorination on one hand and both gel strength and gel thermal stability on the other.
Institute Affairs / xxiii