Some Chemical and Flavor Characteristics of a Milk Proteolysate of Pseudomonas Fluorescens

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Abstract
Analyses were made for chemical components related to flavor during different processing stages. The flavor changed from bitter and undesirable during fermentation to beef broth-like in the low-pressure distilled, autoclaved product. Fractionation on Sephadex G-25 showed 4 peaks of absorbancy at 280 mu. The brothy flavor did not correlate closely with any peak maxima, but was concentrated in the effluent from the 145-ml volume to the 160-ml volume. This effluent contained 17 free amlno acids. Spectrophotometric analyses for carbohydrate, ninhydrin-reactive compounds, phosphate, and furfural derivatives in each case gave a small initial peak and a larger second peak. The latter corresponded closely to the brothy flavor fraction. Of neutral rolatiles detected by gas liquid chromatography none was associated exclusively with the brothy flavor fraction. The heating combinations of amino acids and lactose gave flavors suggestive of but not identical to the brothy flavor. Apparently, the beef broth-type flavor in the processed product resulted from an intricate balance among lactose content, protein breakdown, and browning.