The canned satsuma mandarin together with hesperidin glycosides was stored at room temperature for 6 months. The turbidity in its syrup was analyzed at intervals of 1, 3 and 6 months. Very low concentration of the glycosides, 0.004%, inhibited effectively cloudiness of the syrup. The amount of soluble hesperidin in the syrup was also analyzed by HPLC. Much amount of hesperidin was solubilized in the clear syrup. From these results, the inhibition of turbidness was caused by solubilization effects. The inhibition was not affected by high temperature and acidity. Solubilization of hesperidin by hesperidin glycosides was applied to 50% orange juice. After storage for 1 month, ninety percent of the total hesperidin of the orange juice containing hesperidin glycosides remained in the supernatant. The effects were kept more than 6 month-storage of the orange juice. From these results, it is confirmed that hesperidin glycosides solubilize hesperidin in canned satsuma mandarin and in orange juice and inhibit crystal formation of hesperidin.

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In this paper we studied the possibility of quantification of sugars in aqueous solution by use of Fourier transform infrared (FT-IR) spectroscopy coupled with an attenuated total reflectance (ATR) accessory. Seven kinds of sugar solution (glucose, maltose, sucrose, fructose, lactose, galactose, mannose) were prepared as food models and their infrared spectrum was obtained for different concentrations. It was shown that the shape of spectrum in the fingerprint region for each sugar was quite different. In this region, all peak areas except that of C-OH vibration band, plotted against the concentration of the sugar solution, showed excellent linearity in non-ideal solution like maltose, sucrose, fructose and lactose, while all peak areas showed excellent linearity in ideal solution like glucose. The calibration curve of the peak with non-linearity was fitted well by use of non-linear function of activity coefficient of each sugar solution. Curve-fit of the fingerprint region was attempted to find the most independent wave number, and it was shown that the curve fit spectra with the maximum absorbance of all IR bands was the most independent and the most suitable for quantitative analysis of sugar concentration.

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This paper studies the possibility of quantification of sugar components in food by the use of Fourier transform infrared (FT-IR) spectroscopy coupled with an attenuated total reflectance (ATR) accessory. Four kinds of sugar (glucose, sucrose, fructose, lactose) were prepared as the main sugar components of food and their infrared spectra were obtained for different concentrations. The adsorption in the fingerprint region for each sugar plotted against the concentrations of the sugar solution showed excellent linearity in range of low concentration. Then model juice in which water and there sugars were mixed based on the reference values was prepared. The comparison between the spectrum of model juice and the simulated spectrum by the sum of these sugar spectra showed a good agreement. The same method by FT-IR/ATR was applied to the determination of sugar contents in fruit juice and lactic acid drink which were on the market. The comparison between calculated values of sugar concentrations and the values reported by manufacturers showed a relatively good agreement. It seemed that presented method was effective to analysis of food components, which needs rapidity and low accuracy.

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In the previous paper, we reported that an extract from miso strongly suppressed melanogenesis of B16C7 melanoma cells. In this paper, we purified two melanogenesis suppressing materials. The materials were identified to be linoleic acid and ethyl linoleate by mass spectrometric analysis. Synthesis of tyrosinase, a key enzyme on melanogenesis, of B16C7 melanoma cells was strongly suppressed by addition of linoleic acid to a culture medium, whereas linoleic acid did not inhibit the activity of partially purified tyrosinase from B16C7 melanoma cells.

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The effect of trehalose on the superoxide dismutase (SOD)-like activity of various vegetables was investigated. Six hundred grams of minced carrot and 66g of trehalose were mixed and dried in vacuo at 40°C for 40 h. The drying matter was powdered and then preserved at 40°C for 7 d. The remaining SOD-like activity of the powder was higher than that of the carrot powder alone. Trehalose was the most effective in stabilizing SOD-like activity among various saccharides tested, such as glucose, sorbitol, mannitol, maltose and sucrose. The same effect was observed with other vegetable powders. Trehalose seems to stabilize both SOD and antioxidants in vegetables.

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We have developed a process control system that monitors the concentrations of some constituents of seasoning pickle in a fish soaking process by near infrared (NIR) method and keeps those concentrations constant by fuzzy control technique. NIR method was investigated for determination of glucose, sodium chloride and sodium glutamate in seasoning pickle. Some accurate calibration equations for these constituents were obtained by multiple regression analysis of second derivative spectra and analytical values by the standard methods. These equations were thought to be able to use for process control judging from their accuracy. We developed software for the control system that receives data from NIR equipment and regulates concentrations of the constituents in fish soaked seasoning pickle by switching pumps attached to each concentrated constituent in seasoning pickle. Introducing a fuzzy control technique enabled acute control of concentrations. In a fish soaking experiment with this control system, the concentrations of seasoning pickle constituents were kept almost unchanged. This control system enables us to make products of uniform quality and is useful for reduction of costs and preservation of the environment through the efficient use of seasoning pickle.

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