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Carvacrol, &al and geraniol showed potent antibacterial activity against Salmonella typhimurium and its rifampicin-resistant (Rip) strain as determined in txyptic soy broth and by zone of inhibition on agar-based medium. Carvacrol had the most potent bactericidal activity, with minimum inhibitory and bactericidal concentrations (MIC and MBC) of 250 pg/mL for both tester strains. When tested at 0.5, 1.5 and 3.0% in 1%Tween 20 for bactericidal activity against RifR-S. typhimurium inoculated on fish cubes, carvacrol at 3.0% completely killed the inoculated bacteria, while geraniol killed most of the bacteria, and citral killed the least. Carvacrol and geraniol showed potent antibacterial activity at 1.5%. Bactericidal activity became more evident as storage of fish cubes at 4°C lengthened. The comparable inhibition of these strains of SaZmon@la and species of Gram-negative bacteria by carvacrol and geraniol support their application as potential antibacterial agents in food systems. CarvacrolCitral a (cis) Citral b (trans) Geraniol Fig. l-Structures of carvacrol, citral, and geraniol.

During peanut roasting, pyrazine compounds correlate highly with roasted flavor and aroma. Although roast color measurement is used to predict roasted flavor in peanuts, there are known variations between roast color and flavor development among genotypes. A method for measuring pyrazines using headspace solid-phase microextraction (SPME) was developed and 4 peanut genotypes were roasted and analyzed under a variety of time-temperature combinations. Peanut genotypes differed in roasted flavor and aroma, regardless of roast color. Florida MDR 98 formed the highest levels of pyrazines under the same roasting conditions, followed by Florunner, Georgia Greene, and SunOleic 97R, respectively. Of all pyrazines tested, 2,5-dimethylpyrazine was most highly correlated to roasted peanut flavor and aroma.