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A processing technology for reduced beany flavor full-fat soy paste (FFSP), after most heat treatment of soybeans at 100 degrees Celsius for 0, 5, 10and 15 minutes, is developed. The technology, which incorporates soy proteins as FFSP in comminuted meat products, is found to decrease specific soybean and bitter notes, the two most objectionable flavor characteristics of meat products containing soy additives.

Using fluorescence-activated cytotoxicity selection, followed by colony autoradiographic screening of the surviving population, we have isolated a unique plasmalogen-deficient Chinese hamster ovary (CHO) cell line. The mutant, NZel-1, showed a dramatic (90%) reduction in the rate of biosynthesis and levels of plasmalogens, as determined using short- and long-term labeling with 32[P.sub.i]. Enzymatic assays and lipid supplementation studies showed that NZel-1 was defective in a single step in the biosynthetic pathway for plasmalogens. This step, catalyzed by the peroxisomal enzyme, alkyl-dihydroxyacetone phosphate (DHAP) synthase, is responsible for the introduction of the ether bond found in plasmalogens. The activity of alkyl-DHAP synthase was reduced in whole-cell homogenates from NZel-1 to 18% of wild-type values. Unlike previously described plasmalogen-deficient mutants, NZel-1 contained peroxisomes, as confirmed by immunofluorescence microscopy and catalase release by digitonin. Peroxisomal functions, including the breakdown of very long-chain (>20 carbons) fatty acids, phytanic acid oxidation, and the acylation of DHAP, were normal. Cell fusion studies revealed that the mutation is recessive and belongs to a new complementation group. To our knowledge this is the first report describing the isolation and characterization of a mutant CHO cell line defective in plasmalogen biosynthesis which contains intact, functional peroxisomes. These cells will allow us to examine the role of ether lipids in cellular functions without complications associated with peroxisome deficiency.

The presence of the acyl dihydroxyacetone phosphate (acyl DHAP) pathway enzymes in Saccharomyces cerevisiae was reported. Total membrane fraction of S. cerevisiae exhibited DHAP acyltransferase, sn-glycerol 3-phosphate acyltransferase and acyl/alkyl DHAP reductase. It was shown that expression of these three enzymes is regulated by oxygen. Moreover, the results indicate that the acyl DHAP pathway may be important for non-ether glycerolipid synthesis in this yeast.