The volatile amines dimethylamine (DMA) and trimethylamine (TMA) are common degradation products of TMA-oxide in marine fish- Both compounds are used as important indicators of quality in seafoods. DMA is produced along with an equimolar quantity of formaldehyde by action of an endogenous enzyme found primarily in gadoid fish. TMA is produced in fresh, but not frozen seafoods by a bacterial enzyme. The current AOAC method for determination of TMA in fish is based on the colorimetric estimation of TMA as a picrate salt. This method is not specific for TMA; ammonia, monomethylamine, and DMA also form corresponding picrate salts. Gas chromatography provides a means of separating and quantitating the individual volatile amines. A simple perchloric acid extract of fish is neutralized with potassium hydroxide and extracted with benzene. The amines are then separated by gas chromatography on a porous polymer packed column and detected by using a nitrogen-phosphorus-specific flame ionization detector. The method provides simple, rapid simultaneous quantitation of DMA and TMA, and is applicable to a wide variety of seafoods.

Irradiation of cod fillets with a maximum absorbed dose of 100 Krad extended iced storage life by about 9 days. Further extension of several days resulted when irradiation was combined concurrently with either 60% CO:! packaging atmosphere or sorbate additive. Packaging at low oxygen tension did not provide any additional benefit for irradiated fish. No important difference ln storaae life of treated fish was observed due to-one vs three day postmortem age. The 100 Krad treatment extended grade B quality market life as opposed to grade A (prime quality) market life, Certain physical/ chemical tests were evaluated for their efficacy in estimating spoilage. Concentrations of TMA, DMA, hypoxanthine, APC and pH at spoilage were comparable in control and air-irradiated samples, but were less in sorbate-irradiated fillets.

The addition of oxidizing or reducing agents to minced red hake showed that oxidizing agents reduced the rate of dimethylamine (DMA) and formaldehyde (FA) formation, while reducing agents accelerated their formation. To determine the effectiveness of different oxidizing agents, H202, NaOCl, and KBr03 were added at four levels to minced red hake. DMA, FA, and trimethylamine oxide values showed that 0.05,0.10, and 0.25% levels of H202 were most effective in slowing the reaction rate. Although Instron measurements did not show the oxidizing agents to improve the texture greatly, the sensory panel analysis found the 0.05, 0.10, and 0.25% levels of H202 to have a better texture than the control.Investigations into the utilization of red hake (Urophycis chuss) as a human food have centered around trimethylamine N-oxide demethylase (TMAO-ase), which is thought

Phospholipids of crude and degummed soybean oils were isolated and separated by column chromatography and thin layer chromatography. Standards and specific spray reagents were used to identify the phospholipids. Phospholipids identified in the crude and degummed oils were phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidic acid, lysophosphatidylcholine and lysophosphatidylethanolamine. Several unknown phosphorus‐containing compounds were present. Samples of crude and degummed oil were collected from four soybean oil processors over four consecutive days. Total and individual phospholipids were quantitated by determining the phosphorus content. The total phosphorus content of crude oil varied among companies, with the average ranging from 453 to 676 ppm. The average total phosphorus content of the degummed oil of the four processors ranged from 12 to 84 ppm. Processors removed an average of 86‐98% of the phosphorus present in the crude oil during the degumming process. There was also a daily variation in phosphorus removal within the individual companies. During the degumming process, the proportion of phosphatidylcholine decreased and the proportion of unknown, nonpolar phosphorus compounds increased in samples from all companies. Significantly higher proportions of phosphatidic acid and lyso compounds were found in the degummed oil of some but not all companies.