67C-16 |
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W. Y. SER, Food Science, University of Manitoba, 250 Ellis Building, Winnipeg, MB R3T 2N2, Canada and S. D. Arntfield, Dept. of Food Science, University of Manitoba, Winnipeg, MB R3T 2N2, Canada. One protein isolation method, known as protein micellar mass (PMM) process, has been developed to reduce the problematic antinutritional or toxic factors, including glucosinolates, associated with canola meal. A series of samples representing various stages of the PMM process were produced to assess the extent of glucosinolates recovery during this protein isolation. The total glucosinolate level of all samples was determined using diabetic test kits to monitor glucose released on hydrolysis of glucosinolates by endogenous myrosinase. One objective was to evaluate the use of diabetic test kits as a method for monitor the total glucosinolate levels by comparing it to the standard GC method. A second objective was to determine the mass balance of canola glucosinolates during the PMM process. After mixing a 0.2 g of sample with 1.25 ml of water and letting it stand for three min, the sample solution was taken into the One Touch ® Blood Glucose Meter by capillary action and the glucose concentration was read. Our results showed a good agreement (r=0.94) between the GC method and the estimate of total glucosinolates from glucose released following the hydrolysis of glucosinolates. In the PMM process, only 1.87% of glucosinolate was recovered in protein isolates from canola meal, regardless to the types of ultrafiltration system. A major reduction of glucosinolates was evident in the ultrafiltration steps where about 58% of the glucosinolates recovered in the discarded permeate. However, an overestimation of glucose was observed when looking at total glucosinolate recovery in the proteins, possibly due to the presence of other free glucose in the canola samples. These findings suggest the total glucosinolate levels of canola samples could be easily and rapidly estimated with the use of a diabetic test kit since the results were comparable to those from GC analysis.
Session 67C, Food Chemistry: Food analysis, irradiation and toxicology
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