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Background: Volatile compounds in fish sauce may vary due to the species of fish, ingredients, processing period, temperature, and even the preference of people in each area. It is necessary to study a method of distinguishing the origins of fish sauce. The aims of this paper are to introduce a method to classification of fish sauce origin by means of electronic nose fingerprint and gas chromatography- mass spectrometry of volatile compounds and the two artificial neural networks are used to predict the origins of fish sauce. Methods: Headspace sampling-solid phase microextraction combined with gas chromatography-mass spectrometric analysis and electronic nose were used to analysze volatile compounds in different origins of fish sauce, and these dates predicted the origins of fish sauce by artificial neural networks. Results: 94 volatile compounds were identified by Automatic mass spectral deconvolution and identification system, out of which 44 are from Guangdong, 53 from our laboratory, 51 from Vietnam, 47 and 45 from Thailand. Then electronic nose was applied to identify the origin of fish sauce, and the data were analyzed using principal component analysis and load analysis. The fish sauce from different origin can be classified well on the PCA plot. Lastly, two artificial neural networks are used to predict the origins of fish sauce, and the accuracy rates of radial basis and gradient descent both are 93.33%. Conclusion: That illustrates that we can provide a quick method to distinguish fish sauce products of different origins. These results indicated that the combinations of multiple analysis and identification methods could make up the limitations of a single method, enhance the accuracy of identification, and provide useful information for product development.

Interest in probiotic foods and ingredients is increasing as consumers become more aware of their potential health benefits. The production of these products often involves the use of dry culture powders, and the techniques used to produce such powders often suffer from significant losses of viable cells during drying or require the use of expensive drying technologies with limited throughput (e.g., freeze drying). In this study, the authors examined whether culture survivability during spray drying could be increased via the treatment of two common protein encapsulants with ultra-high-pressure homogenization (UHPH). Lactobacillus plantarum NRRL B-1927 (also known as ATCC 10241), a probiotic strain, was suspended in either soy protein isolate (SPI) or whey protein isolate (WPI) which had been either treated with UHPH at 150 Mpa or left untreated as a control. The suspensions were then dried using either concurrent-flow spray drying (CCSD), mixed-flow spray drying (MFSD) or freeze drying (FD) and evaluated for cell survivability, particle size, moisture content and water activity. In all cases, UHPH resulted in equal or greater survivability among spray dried cultures, showed reductions in particle size measures and, except for one marginal case (CCFD SPI), significantly reduced the moisture content of the dried powders. The combination of these findings strongly suggests that UHPH could allow probiotic powder manufacturers to replace freeze drying with spray drying while maintaining or increasing product quality.

The different volatile compounds in meat of crucian carp under short-term starvation stress were investigated in this study by headspace solid-phase microextraction combined with gas chromatography-mass spectrometric analysis. The detail workflow included Mzmine, analysis of variance, automatic mass spectral deconvolution and identification system (AMDIS), and genetic algorithm. Seventy-two kinds of volatile compounds were identified by AMDIS and 42 kinds of different compounds were selected including 19 aromatics, 7 alcohols, 1 ketones, 2 aldehydes, 2 esters, and 11 unknown compounds. Samples from starvation groups were separated clearly on principal components analysis by 42 volatile compounds. The results suggest that starvation could cause the change of flavor of fish meat, and the changing patterns of these different volatile compounds were revealed. Practical applications In southern China, farm-raised crucian carps are usually put into clean water under short-term starvation for eliminating smell before they are sold. This phenomenon has attracted the attention of the researcher. The present study reveals the changing patterns of volatile compounds in meat of crucian carp by using headspace solid-phase microextraction–gas chromatography/mass spectrometry and starvation groups were classified based on the volatile data. The results demonstrated that combination of Mzmine, ANOVA, AMDIS, and GA can be applied to select different volatile compounds successfully, and this method could be used for the identification of different compounds in similar gas chromatography–mass spectrometry analysis.