The present study investigated the vocabulary for food texture of Japanese consumers through questionnaires in metropolitan area and Kyoto-Osaka-Kobe area. Four hundred and forty five terms collected through questionnaires and interviews to texture researchers in our previous study were judged whether each term was used by consumers or not. In each questionnaire about 200 terms were listed because 445 terms were too many to judge by one subject. Four hundred and forty five terms were divided into 4 groups and two of them were selected at any combination so that combinatorial effect and order effect were reduced. Three thousand five hundred and thirty three subjects judged whether each term was used to describe food properties or not. Out of the 2582 collected questionnaires, 2437 were completed and thus used for further analysis. The criterion of the percentage of judgments as food expressions was 75% or greater and 135 terms met this criterion with a confidence level of 95%. The terms judged as food expressions at 90% or greater were 66 terms with a confidence level of 95% such as “katai (hard)”, “creamy”, “saku-saku (crispy)”, “pari-pari (crispy)” and “neba-neba (sticky)”. They were considered to be the core terms of texture vocabulary of Japanese consumers.

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Fish sauces made from Japanese common squid internal organs (IKA-ISHIRU) or whole sardines (IWASHI-ISHIRU), have been produced in Noto peninsula of Ishikawa prefecture. Seven kinds of polyamines i.e. histamine(Him), tyramine(Tym), putrescine(Put), cadaverine(Cad), agmatine(Agm), tryptamine(Tpm) and spermidine(Spd) in commercial ISHIRU were analyzed, and changes in the composition of these polyamines during the processing of ISHIRU were also investigated. The major polyamines of both commercial ISHIRU were Him, Spd, Tym and Put, and IWASHI-ISHIRU contained larger amount of Him than IKA-ISHIRU. When the both ISHIRU are experimentally fermented, the contents of Cad, Agm and Spd decreased in IKA-ISHIRU during the fermentation and reached the steady states over about 8 month. Other polyamines of IKA-ISHIRU showed the same levels during the fermentation. In the case of IWASHI-ISHIRU, although histamine increased slightly during the fermentation until 6 month , other polyamines kept the same levels during the fermentation. From these results, it is presumed that the contents of polyamines in ISHIRU were related with a freshness of raw materials and ingredients, and that the microorganisms like histamine-producing bacteria were hardly concerned in the formation of polyamines in ISHIRU.

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”Tanbaguro” is a local variety of Japanese soybean (Glycine max) that is characterized by large seed size and a black seed coat. We intended to determine a method for determining the geographic origin of Tanbaguro seeds by their inorganic element composition. Seed samples of 48 Tanbaguro varieties and eight ”non-Tanbaguro” black soybean varieties cultivated in different years were collected in Japan and China. Eight inorganic elements (Al, Mn, Fe, Ni, Cu, Zn, Sr and Ba) of these samples were estimated using ICP-AES (Inductively coupled plasma atomic emission spectrometer). Significant differences were observed between Japanese and Chinese samples in the contents of four elements (Al, Fe, Cu and Sr). Principal component analysis samples could generally be divided into two groups : those cultivated in Japan and those cultivated in China. Various combinations of inorganic elemental contents were used to perform the linear discriminant analysis (LDA). LDA performed by eight elements classified with a confidence of 96%, and country of origin could be predicted with confidence of 100%. Even when four elements (Al, Mn, Sr and Ba) were used, it was possible to distinguish whether the country of cultivation was Japan or China. LDA performed by Al and Fe contents, selected by stepwise discriminant analysis, classified and predicted with a confidence of only 89% and 79%. However, since all samples cultivated in China could be correctly classified and predicted, this discriminant model was useful for the screening of samples. Therefore, the applicability of this method for determining the geographic origin of Tanbaguro bean varieties was demonstrated.

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The emulsifying properties of egg yolk with diacylglycerol (DAG) as the oil phase were investigated and compared with triacylglycerol (TAG) as the oil phase. The fatty acids of the DAG and TAG samples were adjusted to nearly the same composition before being used in this experiment. The effects of egg yolk concentration, pH, and the added salt on the emulsifying properties were evaluated by the interfacial tension, flow characteristics, oil droplet size and emulsifying capacity of the emulsion.
The interfacial tension in the TAG-egg yolk solution interface decreased significantly depending on the concentration of the egg yolk. The decrease was most marked at pH 6, and at pH 3 and 9 albeit to a lesser extent. The decrease in interfacial tension of DAG was less than that of TAG and the differences associated with decreased pH were also small. The viscosity of the TAG emulsion (egg yolk 1%, oil volume fraction 0.5) was not largely affected by pH. DAG at pH 6 produced a high viscosity emulsion, but droplet size was not affected by sample oil and pH. The emulsifying capacity of both oil samples was markedly higher at pH 6 compared to pH 3 and pH 9, which was more conspicuous in TAG. While the addition of NaCl did not affect the interfacial tension of TAG, it decreased the interfacial tension and viscosity of emulsion of DAG. The emulsifying capacity of both TAG and DAG increased after the addition of NaCl, with the magnitude of the increase being larger in DAG.

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[in Japanese]

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[in Japanese]

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