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A previously reported method of preparing rapeseed protein concentrate (RC) involving 2% sodium hexametaphosphate (SHMP) was modified to reduce SHMP lost in the effluent, to produce a product with higher protein, lower phosphorous content and improved color close to that of rapeseed flour and promine D. Addition of 0.25% Na2S205 to the 0.25% SHMP extractant improved color but had little effect on flavor. Except for nitrogen solubility, whippaachieved the fust two objectives. Double washing of precipitate with 50% alcohol or precipitation in 15 or 30% alcohol yielded RC with color close to that of rapeseed flour and promine D. Addition of 0.25% NazS2Os to the 0.25% SHMP extractant improved color but had little effect on flavor. Except for nitrogen solubility, whippability and viscosity, the functional properties and chemical scores of the improved RC's were similar to the control RC (2% SHMP). ~~ ~ ~Grams nitrogen recovered per lOOg nitrogen in rapeseed flour Decrease in yield between after washing and drying was attributed t o losses during transfer of precipitate from centrifuge bottle to drying pans or bottles to weighing containers. Adhering solids in the containers were considered losses.

A paired-ion liquid chromatographic (LC) technique coupled with fluorometric detection to determine riboflavin in various food matrices is described. Chromatograms of many foods showed 2 peaks of interest due to presence of riboflavin and flavin mononucleotide (FMN). Relatively high levels of FMN were found in raw beef, corned beef, chicken liver, and canned mushrooms. When riboflavin and FMN contents were summed, LC values were comparable to those obtained by the AOAC standard procedures. The LC technique was sensitive, rapid, and simple, yielding a mean standard deviation of 3.1% which was comparable to the AOAC fluorometric method (3.0%) and better than the AOAC microbiological assay (9.6%). Mean spike recoveries were 91.8% for LC compared to 90.5% and 89.6% for the AOAC fluorometric and microbiological methods, respectively.

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