Nine cooperating laboratories, distributed throughout the United States, determined the interlaboratory reproducibility of a sensitive, selective method for isolation of Campylobacter jejuni and Campylobacter coli from foods, and determined the prevalence and distribution of the organism in retail meats. A double-blind inoculated/recovery experiment demonstrated the ability to detect two cells of C. jejuni and C. coli per g of meat at a rate of 96% among the cooperating laboratories. However, a 7.5% false-positive rate for the presumptive detection of the organism was also reported. Samples of ground beef, beef flank steak, lamb stew meat, broiler chicken, pork sausage (without antimicrobials), and pork chops were selected to assess the presence of campylobacters. Each cooperator purchased five of each of the above samples from the refrigerated case of two retail outlets at quarterly intervals throughout the year. A total of 2,160 retail samples were analyzed for the presence of C. jejuni and C. coli. Results indicated that about 30% of the 360 chickens sampled yielded the organism. Analysis of 1,800 red meat products yielded campylobacters at a rate of about 5.1%. Pork samples yielded C. coli and other meats yielded C. jejuni. Higher numbers of isolations from the red meats were made during June and September (8.6%) as compared with December and March (4.2%). These results provide a baseline, for the prevalence of campylobacters in these selected foods, and also support epidemiologic data associating mishandled foods of animal origin as a potential vehicle in human gastroenteritis.

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The acids from autoxidation of methyl linoleate have been analyzed as their methyl esters by combined capillary gas chromatography‐mass spectrometry (GC‐MS). The principal components were hexanoic, trans‐2‐octenoic, suberic and azelaic acid. Minor components included formic, pentanoic, heptanoic, trans‐2‐heptenoic, octanoic and nonanoic acid. In addition,trans‐2,3‐epoxy‐octanoic acid was isolated as its methyl ester by preparative GLC and was identified by means of NMR, high resolution MS, IR and by conversion to a known derivative.

centages of carbon and hj7drogen were then determined for dextrose, cystine, glycine, and 2-naphthalenesulfonic acid. For each compound the separate analyses were run on separate days. All LITERATURE CITED