Potassium bromate, which contributes to the formation of disulfide bonds in wheat protein in dough and increased gas-retaining capacity, has been used as a bread improver since the 1910s. However, it has been reported that potassium bromate has a mutagenicity based on experiments with rats. Thereby, the regulations in Japan stated that in the case of bread, residual bromate must be reduced or removed from the final products. Residual contents of potassium bromate in bread extracts prepared by the improved method were measured by high performance liquid chromatography (HPLC) with post-column reaction for the coloring of bromate. No residual bromate was detected in Pullman-type breads with 13 or 15mg potassium bromate added per kg of flour. On the other hand, the residual bromate determined in open-top type bread with 9-30mg potassium bromate added per kg of flour, was found localized on the top of crust put out of the baking pan. Reducing agents such as L- ascorbic acid (AsA), cysteine and glutathione and ferrous sulfate were added to the open-top type bread to reduce the residual bromate. Adding both AsA and ferrous sulfate accelerated the decrease in the residual bromate in the open top-type bread.

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To determine the characteristics of antioxidative activity of dipeptides, anserine (Ans), carnosine (Car) and their mixture (AC mix) isolated from a chicken extract, we evaluated the protective effect of these dipeptides on the protein degradation by reactive oxygen species, ClO⋅, OH⋅ and ONOO⋅, and compared their activities with other antioxidants including vitamin C (V. C), vitamin E (V. E), reduced glutathione (GSH), epigallocatechin gallate (EGCG) and quercetin (Qur). When AC mix was assayed by a diphenylpicrylhydrazyl (DPPH) method commonly used to evaluate the activity in foods, the antioxidative activity of AC mix was only 1/6700 of EGCG, 1/2500 of Qur and 1/1000 of both V. C and V. E. In the evaluation of protective effect on the protein degradation by reactive oxygen species, Ans, Car and AC mix revealed comparatively strong antioxidative activities against ClO⋅ and ONOO⋅ as well as GSH and V. C. V. E, Qur and 50μM of EGCG showed a weak antioxidative activity against ClO⋅, but a remarkably strong antioxidative activity against OH⋅. On the other hand, Ans, Car and AC mix had a weak protective effect on OH⋅ degradation. V. C was also a weak antioxidant against OH⋅ as well as AC mix and GSH, but showed a strong antioxidative activity against ONOO⋅. From these findings, it is strongly suggested that each antioxidant has a specificity against reactive oxygen species in their antioxidative activity and an appropriate combination of antioxidant intake might be very important to prevent injury of body elements by reactive oxygen species generated during an energy metabolism in human body.

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A multi-band image scanner was developed in order to scan a sample at a specific wavelength. A band-pass filter inserted in the light path of the scanner enabled us to acquire the image information at the specific wavelength. An Andes melon was cut into halves and its cut surface was scanned at 676nm, at which the absorbance was reported to correlate inversely with sugar content. The intensity at each pixel of the acquired image was converted into absorbance based on the definition of absorbance. Then cylindrical flesh was extracted from the half-cut sample as a calibration sample. The image scanning and the Brix sugar content measurement of the calibration sample were repeated to acquire a series of data of the absorbance and the sugar content. Linear regression analysis was applied to these data to develop a calibration curve of sugar content versus absorbance. The calibration curve was applied to each pixel of the half-cut sample image in order to construct a sugar distribution map. In the same way, the calibration curve and the sugar distribution map of a Quincy melon were developed. The correlation coefficients of these calibration curves were 0.980 and 0.956, respectively, and their actual sugar distributions were accurately reflected in the sugar distribution maps. Therefore, it can be concluded that the multi-band image scanner is useful for the near-infrared imaging spectrometry.

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We examined the blend for the market on the basis of 3 varieties of low-amylose rice. (1) The 20% of blends of the "Milky queen" and "Snow pearls" were suitable in the palatability evaluation. (2) Hardness was selected as the item to use the evaluation of blend rice from correlation with cohesiveness of palatability evaluation and fluctuation range of palatability evaluation. (3) The multiple regression model was made by the cohesiveness of palatability evaluation of low-amylose blend as purpole variable, and by the hardness as explanation variable. (4) The principal component analysis using variable of a multiple regression formula was examined. The classification of low-amylose blend rice in terms of the evaluation standard of the cohesiveness of the palatability evaluation from principal component load quantity and also principal component scores was examined.

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We examined the property that is related to the palatability of the blend of Koshihikari and Akitakomachi. (1) The suitability was obtained in 60% of blends of Koshihikari in palatability evaluation as cooked rice. (2) Cohesiveness of the palatability evaluation admitted the significance positive correlation with the hardness obtained by cooked rice taste analyzer. It may be possible that this phenomenon becomes the guideline of the measurement of the blend of Koshihikari and Akitakomachi.

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We examine the evaluation of the suitability of cooking cooked rice. (1) The evaluation of the "Akibare" is the best in the palatability evaluation for Sushi rice and fried rice. The evaluation of the 100% Koshihikari was best in seasoning tasted rice. (2) By principal component analysis about the properties, that is related to palatability of the cooking cooked rice, it was found that sushi rice and fried rice resemble well and the trend of tasted rice differs.

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During alcoholic fermentation trans- and cis-resveratrol were rapidly extracted from grape skin along with the rise in the alcoholic concentration and reached equilibrium six days after the start of maceration. The increase of trans-resveratrol was shown to be ahead of that of the cis isomer, but the trans isomer decreased at the late stage. It was, therefore, assumed that trans-resveratrol would be converted to the cis isomer by the action of a possible yeast isomerase. In addition, on the process of malolactic fermentation resveratrol levels were found to increase accompanied by a decrease in piceid concentration. This means that the increase resulted from the hydrolysis of piceid by β-glucosidase activity produced by lactic acid bacteria involved in the malolactic fermentation.

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