Aucubin (AC) is an iridoid glucoside contained in Aucuba japonica Thunb. and Plantago asiatica L. AC was hydrolyzed by β-glucosidase to aucubigenin (ACN), a reactive aglycone, and it reacted with a certain amino acid to form a red pigment. The conditions of this coloring reaction were similar to those of the red pigment formed from geniposidic acid (GSA) and amino acid. It was suggested that ACN became a dialdehyde form in the aqueous solutions and then reacted with amino group of amino acid to form the intermediate by amino-carbonyl reaction. Further, the coloring reaction was promoted with heating and acidity by organic acid, and the reaction mixture deepened with the passage of time and finally gelled. The molecular mass of the pigment prepared from AC and glutamic acid showed higher than that of the pigment produced from GSA under the same reaction condition. The color of the pigment produced from AC and glutamic acid showed high stability in a pH range of 4-7, however, it precipitated at pH 3. The color deepened and decreased the red tone with heat treatment. Light exposure caused hypsochromic shift and fading of the color. The red pigment produced from a mixture of AC and GSA showed red color tone depending upon the proportions of these iridoid glucosides and was not separated into each pigment originated from AC or GSA by a gel chromatography. These results suggested that the forming mechanism of the red pigment produced from AC was a similar to that of GSA.

View full abstract

Changes in soymilk color during soybean grinding were investigated. With soymilk prepared from Fukuyutaka (normal type) seeds, an increase in the soybean grinding temperature caused decreases in the Hunter's chromatic L and b values of the soymilk and an increase in its a value. These changes correlated with those in the soymilk's peroxide. When soybean seeds lacking all the lipoxygenase isozymes (Kyushu 111) were ground under the same conditions, hardly any change in the soymilk's color was observed. These findings suggest that the changes in soymilk color during soybean grinding are caused by a lipid oxidative reaction of lipoxygenases. From the behavior of the color observed on ultrafiltration, we inferred that the yellow pigments, which reflect the b value of soymilk, were water-soluble low molecular compounds. Also, we found from the difference spectrum of soymilk whey after the enzyme reaction that the maximum decrease in absorbance occurred at approximately 420nm. On analysis of this soymilk whey using high-performance liquid chromatography (HPLC) at 420nm, we found that many peaks had disappeared following enzyme reaction. The main peak that disappeared had a maximum absorption wavelength at 415nm and was distinctly different from well-known carotenoids on its spectral characteristics.

View full abstract

Volume change of fish flesh, that is swelling or shrinking is caused by a long time immersion in salt solution corresponding to their concentration. The amount of penetrated salt cannot be estimated by conventional diffusion model in such case. So, time variation in penetration of salt into fish flesh accompanying swelling or contraction, and relationships between an amount of penetrated salt and volume change of flesh were studied. On the other hand, model equation describing these relationships were derived as follows with some assumption and approximation, and compared with experimental results. Salt are transported by diffusion and by flow of absorbed or released solution. Concentration of these solution were assumed to be the same concentration of the outer solution. No matter what the volume change was swelling or shrinking, the model equation explained the experimental results well.

View full abstract

We cultured thick bean sprouts by immersion in a 10 ppm phytohormone solution of auxin (IAA), cytokinin (CBA), abscisic acid (ABA), or gibberellin (GA3), and evaluated changes in the content of each nutrient at the time of harvesting in comparison with conventional culture methods as a control. After cultivation by the phytohormone treatment, both soybean and mung bean thick sprouts showed a similar state of growth. In both types of thick bean sprouts, changes in the contents of nutrients were affected by the growth state after sprouting. Compared with the control method, the contents of nutrients increased after the culture with IAA or CBA with growth inhibitory effects but decreased after the culture with ABA or GA3, with growth promoting effects. The contents of major nutrients (protein, lipids, sugars, fibers, and ash) gradually decreased in the early period of culture (1-3 days) but markedly decreased in the middle period (4-5 days) appropriate for harvesting and the terminal period (6-7 days) showing root growth and cotyledon formation. The contents of moisture and vitamin C (L-AsA) showed reciprocal changes to those of the major nutrients, increasing with culture period. Niacin and vitamins B1 and B2 as water-soluble vitamins decreased from the early to middle period of culture but were slightly increased in the terminal period, reaching a peak. The major nutrients and L-AsA increased after the culture with IAA or CBA but decreased after the culture with ABA or GA3 suggesting disadvantages of the latter phytohormone cultures. The contents of niacin and vitamin B1 and B2 did not markedly differ between the phytohormone-treated and control cultures. Phy to hormone treatment of cultures produced differences in the contents of nutrients in thick bean sprouts according to the degree of involvement of each phytohormone in growth after sprouting. After the culture with IAA or CBA which inhibit growth, nutrient degradation and synthesis became slow, and growth-associated nutrient consumption decreased. On the other hand, after culture with ABA or GA3 which promote growth, the reverse phenomenon occurred ; i.e. the contents of nutrients decreased compared with controls.

View full abstract

The antioxidative activities of warm water-extracts of whole barley and classified barley (referred to Draft barley hereafter) were compared with those of green tea and coffee bean. The Draft barley was prepared from whole barley grain by using polishing roll equipped with the Draft barleyclassification system. The antioxidative activity was determined by the Rancimat analysis for the evaluation of the induction time (I.T., Rancid point) and the Active Oxygen Method (AOM) test. The I.T. values of tested oil were delayed by adding the Draft barley extract. Especially, those of whole barley and Draft barley 2 showed higher values than those of others. The antioxidative activity of the roasted barley extract was significantly higher than that of the raw barley extract, and the longer barley was roasted, the period roasting barley was, the higher the antioxidative activity became. The antioxidative activities of the roasted Draft barley were found in its water and ethanol extracts but not observed in the diethyl ether and chloroform extracts. The preventive effect on deterioration of soybean, whale and sardine oils was increased in proportion to the dose of the barley extract. The antioxidant activity decreased in the order of the water extracts of green tea, coffee bean and Draft barley.

View full abstract

Extraction of lipid from the freeze-dried (FD) residue of "IKA-ISHIRU" (squid fish sauce) was carried out with supercritical carbon dioxide (SC-CO2) at the conditions of 150-350kg/cm2 and 35-70°C. The effect of ethanol as an entrainer was investigated. SC-CO2 extracted about 22% of lipid from the FD residue of "IKA-ISHIRU" (extraction at 250kg/cm2, 45°C, 4 hr) When ethanol was added to SC-CO2, the extraction ratio of lipid showed a higher value. This result indicated that ethanol acted as an entrainer and that the addition of ethanol to SC-CO2 was fairly effective for the extraction of lipid. These extracts were analyzed for fatty acid compositions by gas-liquid chromatography (GLC). The major fatty acids of these extracts were 14:0, 16:0, 16:1 (n-7), 18:0, 18:1 (n-9), 18:1 (n-7), 18:2 (n-6), 18:4 (n-3), 20:1 (n-11), 20:1 (n-9), 20:4 (n-6), 20:5 (n-3), 22:1 (n-11 and n-13), 22:1 (n-9), 22:6 (n-3). The sum of these fatty acids was more than 85% of the total fatty acids. The major polyunsaturated fatty acids were 22:6 (n-3) (DHA, 22.7%) and 20:5 (n-3) (EPA, 8.94%). The amount of total fatty acids of SC-CO2 extracts showed a higher value than that of CHC13-CH3OH extracts.

View full abstract

As a cultivation method of thick soybean sprouts, soybean were intermittently immersed after sprouting in a mixed phytohormone solution (total phytohormone, 10 ppm) containing auxin, abscisic acid, cytokinin, and gibberellin at various ratios. Growth, food physical properties, water content, and surface color of thick soybean sprouts were evaluated. In the hypocotyl and root growth of thick soybean sprouts, auxin+abscisic acid and cytokinin+abscisic acid at a high ratio of auxin or cytokinin inhibited extension and the number of root hairs and increased thickening and food physical properties, improving quality. These combinations appeared to be appropriate. The yield was closely associated with the water content. Auxin+gibberellin and cytokinin+gibberellin at a high gibberellin ratio, which only slightly inhibited growth, increased the water content and quantity, resulting in an increase in the yield. These combinations also appeared to be appropriate. For color numerically evaluated by Hunter's method, the combinations containing a high ratio of auxin or cytokinin, which only slightly inhibited growth, were appropriate. Combinations containing a high ratio of gibberellin, which only slightly inhibited growth, caused slight milky yellow. However, this tone was not incompatible macroscopically. The combinations containing a high ratio of auxin or cytokinin were appropriate for cultivation of thick soybean sprouts by this method and very useful for improving quality. Concerning the yield which is economically important, the feasible amount slightly decreased as the degree of growth inhibition increased. However, when cultivation conditions such as the concentration of the mixed phytohormone solution and treatment period and time are arranged, this method appears to be more appropriate than dipping at cultivation in a single phytohormone (10 ppm) solution.

View full abstract

Cotyledon tissues of kidney beans were prepared by soaking of cotyledons in water at 25°C for 22 h followed by cutting into about 5×5×1 mm slices. The cotyledon tissues were heated in a presence of some seasonings (sodium chloride, sucrose, ethanol, acetic acid and sodium glutamate) and softening degree of tissues and loss of birefringence of starch inside tissues were measured. Softening of cotyledon tissues was depressed by the addition of sodium chloride (more than 1.0M), sucrose and ethanol, while it was stimulated by the addition of acetic acid and sodium glutamate. On the other hand, starch gelatinization inside tissues was depressed by the addition of sodium chloride, sucrose and sodium glutamate, while it was stimulated slightly by the addition of ethanol and acetic acid.

View full abstract

The quality of natto depends on the quantity of sticky materials (SM) which are produced by the starter, Bacillus subtilis (natto) strain. In this study, we found that phytone, papain-digested soy protein, significantly enhanced the SM production by B. subtilis (natto). L-Gluta-mate was also found to exhibit the same effect. When 1% phytone was added to SG medium, SM was produced 5-10 times more than that in the standard SG medium. Phytone appeared to enhance both the SM production and cell growth, suggesting that it plays some role in the increase of SM and cell growth. L-Glutamate (3-5%), on the other hand, enhanced SM production but not cell growth. We therefore deduced, that the effect of phytone was different from that of L-glutamate.

View full abstract