To prevent the adulteration of agricultural resources and provide a solution to enhance the green coffee bean supply chain, authentication using the near-infrared spectroscopy (NIRS) technique was investigated. Partial least square with discrimination analysis (PLS-DA) models combined with various preprocessing methods were built from NIR spectra of 153 Vietnamese green coffee samples. The model combined with the standard normal variate and the first order of derivative yielded excellent performance in predicting coffee species with the error cross-validation of 0.0261. PLS-DA model of mean centre and first-order derivative spectra also yielded good performance in verifying geographical indication of green coffee with the error of 0.0656. By contrast, the predicting abilities of post-harvest methods were poor. The overall results showed a high potential of the NIRS in online authentication practices.

Do words evoke taste feelings? A comparison between French, American and Vietnamese students.French students (150), American students (150) and Vietnamese students (180) participated in two successive tests to study whether certain words would elicite taste evocations. The first test was a free association test: Subjects had to write down on a sheet of paper what came spontaneously to their mind when reading a given word. The second test was a test of directed association: Subjects had to estimate numerically the association between a series of words and each of the four tastes: sweet, sour, salt and bitter. The results show considerable differences between the three groups of subjects, even though the general structural organization of the four tastes is somewhat similar for all groups. For example, the word strawberry is associated only very slightly with the taste sweet for French subjects whereas it is associated very strongly with sweet for American subjects: it obtains a score comparable with the word honey. For Vietnamese subjects, this word is also associated strongly with sweet, but even more with acid. These results can be explained by differences in both food behavior and life experience. The results also can explain why certain interactions between odors and tastes appear in one culture but not in another.

Wheat germ oil (WGO) is well-known as a good source of vegetable oil due to its nutrients and health benefits. Emulsification is a process that improves the incorporation of oil into food. High-pressure homogenisation (HPH) is a nonthermal and soft technique with enormous potential in oil-in-water emulsification. This paper focussed on the application of HPH for emulsification of WGO-in-water system. Influences of homogenisation pressure (100-300 bar), oil fraction (10-20% v/v) and lecithin adding (0-0.2% w/v of content) on the homogenisation were evaluated based on distribution of particles diameter and homogenisation efficiency. The increase in operating pressure and lecithin ratio decreased the particle size and increased the emulsion stability, and vice versa for oil fraction. The findings imply that the investigated factors significantly influenced particle size and emulsion system stability. The regression model between mean particle diameter and technical conditions of emulsion was established. With HPH treatment conditions of 300 bar operating pressure, 10% (v/v) oil fraction and 0.2% (w/v) lecithin created an emulsion system with a mean particle size of 3.32 µm, more than 50% of the volume of particles smaller than 1.5 µm of diameter and the homogenisation efficiency of 98.61%. HPH exhibits high efficiency and potential in WGO-in-water emulsification application.

Gamma-aminobutyric acid (GABA), a main inhibitory neurotransmitter in brain, is a nonproteinogenic amino acid. The production of GABA from rice bran by lactic acid bacteria (Lactobacillus brevis) is an approach for maximising the potential of agricultural byproduct and reducing production cost. The use of media additives enhances the efficiency of GABA production, but their effects on cells and biomass in fermentation must be assessed to determine the appropriate concentration and efficiency. The influences of CaCl 2 (0-1.5% w/v), Tween 80 (0-0.9% w/v), MnSO 4 (0-0.6% w/v) and Pyridoxine hydrochloride (0-90 ppm) at different concentrations on GABA production by defatted rice bran extract fermentation using Lb. brevis VTCC-B397 were evaluated. The changes in cell density, GABA content, reducing sugar content and pH value were observed. Consequently, the impact of media additive compounds on growth, development and GABA synthesis of Lb. brevis was demonstrated. Results showed that CaCl 2 , MnSO 4 and Tween 80 positively affected GABA production from defatted rice bran extract by fermentation method.

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