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Foodborne hazards in seafood have only recently received increased attention in Singapore since the illness outbreak in 2009 that was associated with consumption of Indian rojak (a traditional salad of fruits, vegetables, and seafood). The microbiological quality of seafood must be evaluated for assurance of food safety. The aim of this study was to evaluate the microbiological quality and to determine the prevalence of Salmonella and Vibrio spp. in seafood sold in Singapore. A total of 116 samples (41 prawn, 44 shellfish, and 31 fishball samples) were collected from major supermarkets and wet markets in Singapore. The mesophilic and psychrotrophic bacterial counts for prawn, shellfish, and fishballs were 2 to 7 log CFU/g. One Salmonella Lexington strain was isolated from a thawed-frozen shellfish product and two Vibrio parahaemolyticus strains were isolated from commercial fishball and shrimp meat products. Thus, seafood sold in Singapore has the potential to be contaminated with Vibrio spp. and Salmonella, and proper handling at food service establishments is required to ensure food safety. Effective control measures also are needed to prevent cross-contamination during postharvest seafood processing.

Organosulfur compounds (OSCs) in coffee remain challenging to analyze by conventional gas chromatography (GC) due to their low concentrations amid coffee's complex matrix and susceptibility to chiral-odor influences. In this study, multidimensional GC (MDGC) methods were developed to profile OSCs in coffee. Conventional GC was compared to comprehensive GC (GC×GC) for untargeted OSC analysis in eight specialty coffees, and GC×GC was found to improve the fingerprinting of OSCs in coffee (50 vs 16 OSCs identified). Of the 50 OSCs, 2-methyltetrahydrothiophen-3-one (2-MTHT) was of high interest due to its chirality and known aroma contribution. Following that, a heart-cutting method for chiral GC (GC−GC) was developed, validated, and applied to the coffees. The mean enantiomer ratio of 2-MTHT was observed to be 1.56 (R/S) in brewed coffees. Overall, MDGC techniques allowed for more comprehensive analyses of coffee OSCs, from which (R)-2-MTHT was found to be the predominant enantiomer with the lower odor threshold.