Gas chromatography-mass spectrometry combined with multivariate data analysis as a tool for differentiating between processed orange juice samples on the basis of their volatile markers

The contents of volatile aroma compounds in orange juice vary after high hydrostatic pressure (HHP) processing and pasteurization, and hence gas chromatography-mass spectrometry has potential for discriminating between orange juice samples according to the processing method. Effects of HHP processing and pasteurization on orange juice were investigated immediately after processing and after storage for 28 days at 4 degrees C. Processing decreased the contents of most terpenes and esters and increased those of alcohols and aldehydes. Volatile compounds that could serve as discriminant indicators of HHP processing and pasteurization were heptanal, (E)2-heptenal, (E)-2-nonenal, and d-carvone and beta-terpineol, p-mentha-1,5-dien-8-ol, carveol, and beta-copaene, respectively. The discrimination abilities of pH, ascorbic acid, total soluble solids, and color were compared with those of volatile compounds, which were found to be lower. The compounds d-carvone and beta-terpineol could be used as discriminant indicators of HHP-treated and pasteurized orange juice, respectively, throughout the storage period.