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Lactobacillus paracasei MCC1849 (LP) has the potential to modulate immune function. The purpose of this study was to investigate the impact of flavor compounds on changes in sensory characteristics during refrigerated storage of a functional LP-fermented dairy beverage. A sample containing 1 × 108 cells/mL viable LP stored at 10 °C for 0, 1, or 2 weeks was evaluated by a trained panel. The scores for 'odor', 'afterflavor of fermented odor', 'fermented odor', and 'acidity' increased significantly. Three types of gas chromatographymass spectrometry for volatiles in the solvent extract and headspace gas, and also for hydrophilic compounds were performed. The compounds related to the change in four sensory attributes were examined by partial least squares regression analysis. A non-stored sample with a flavor composed of 13 compounds related to the attributes replicated the fermented odor characteristics of the 2-weeks-stored sample. [ABSTRACT FROM AUTHOR]

Lactobacillus paracasei MCC1849 (LP) has the potential to modulate immune function. To develop a functional LP-fermented dairy beverage, changes in intensities of odorants during two weeks of refrigerated storage were investigated by gas chromatography-olfactometry (GC-O, Charm Analysis™). A fermented dairy beverage containing 1×108 viable LP cells/mL, 0.8% non-fat milk solids, and 0.1 % milk fat was prepared, and then stored at 10°C for 0, 1, or 2 weeks before solvent extraction. GC-O of the volatiles in the resulting extracts detected 34 odorants, of which 29 were identified. Among the identified compounds, 4-(4'-hydroxyphenyI)-2-butanone (raspberry ketone) was also detected by GC-mass spectrometry, representing the first identification of this compound as an odorant in fermented dairy products to our knowledge. Principal component analysis of the GC-O data permitted discrimination among the 3 stored samples according to duration of storage, and clarified the major odors contributing to the change in odor characteristics during storage. [ABSTRACT FROM AUTHOR]

Changes in volatile compounds during early storage of an aseptic-cup (AC) coffee beverage without milk and sugar were examined. AC coffee samples were stored at 10°C for 0, 1, and 2 weeks. Retronasal aroma (RA) compounds of the AC samples were collected using a retronasal aroma simulator (RAS) coupled to a solid-phase microextraction (SPME) fiber and then analyzed using gas chromatography-olfactometry (GC-O) and gas chromatography-mass spectrometry (GC-MS). The GC-O analysis detected 17 odor compounds. Changes in the compounds during 2-week storage were quantitatively analyzed using selected ion monitoring GC/MS. Statistical analyses of the peak areas showed that eight compounds decreased significantly (p < 0.05) during early storage, and that trends of the decreases differed among the compounds. Furthermore, a duo-trio test using an analytical sensory panel confirmed that the aroma of the 2-week sample was similar to that of the 0-week sample upon addition of the model flavor (composed of the eight compounds) to the 2-week sample. [ABSTRACT FROM AUTHOR]