Processing of soybeans for industrial manufucturing of Tempe, a traditional fermented soybean food in Indonesia, was investigated. The bacterial count of Tempe prepared from peeled soybeans was lower by 2 orders than those prepared from unpeeled soybeans. The bacterial count of Tempe was lowered by soaking peeled soybeans in an aqueous solution of an organic acid. Acetic acid gave the most effective results among organic acids employed. Namely, 0.2% level of acetic acid, 1.0% level of lactic acid, succinic acid and tartaric acid, or 3.0% level of citric acid was required in order to lower the becterial count of Tempe to 10 4/g level. It was appropriate to soak peeled soybeans in an aqueous solution of acetic acid at 17 to 20°C for 3 to 4 hours. Tempe prepared from peeled and pressure-steamed soybeans was superior in taste to the one prepared from boiled soybeans. Steaming the peeled and soaked soybeans under O.8kg/cm2 for 3 to 7 minutes made the hardness of the soybeans to 1.0 to 1.5kg which gave appropriate condition to make Tempe. Satisfactory Tempe manufacturing may include the following process: peeling soybeans; soaking the peeled soybeans in 0.2% solution of acetic acid for 3 to 4 hours; draining the beans; and steaming under 0.8kg/cm² for 3 to 7 minutes.

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Nose cartilage of chum salmon, which had been stored at-40°C, was thawed and cut into 2mm thick slices, followed by curing in 4% acetic acid solution up to 168 hours. Sensory panel members noticed that the color of cartilage turned into white, its fishy odor disappeared, and the texture became soft and palatable by curing. During curing process, the hardness value measured by a Texturometer and the water holding capacity measured by a centrifugation method decreased. A significant correlation was seen between the hardness and the water holding capacity. pH value of the cartilage lowered rapidly to that (pH3.0) of soaking solution containing acetic acid. A remarkable decrease was shown in the contents of ash and carbohydrate during the curing process. After 168hr of curing, the calcium and mucopolysaccharide contents decreased to half of those of untreated sample. The collagen content was unchanged. From these findings, the softening of the cartilage during the curing process will be explained by the hypothesis that the matrix of cartilage becomes porous and fragile because cations which are responsible for cross-link formation in mucopolysaccharide are replaced by H⁺ ion of acetic acid, and consequently Ca⁺⁺ ion and mucopolysaccharide are released from the matrix.

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Eleven kinds of foods (rice, soy bean, potato, sweet potato, Japanese radish, carrot, apple, pear, persimmon beef and chicken) were pressurized at hydrostatic pressure of 5000kg/cm² at room temperature for 10min. Effect of pressurizing on appearance, odor, taste and texture of food was evaluated by sensory tests. Changes in hardness and color were measured by a Texturometer and a Color difference meter, respectively. The fracture load and fracture deformation of Japanese radish were also measured by a Rheoner. The surface structures before and after pressurizing were observed by SEM. Furthermore, after pressurizing, the permeation rate of sodium chloride into Japanese radish during NaCl aqueous solution soaking and the browning rate of potato were studied. The appearance, odor, taste and texture of almost all foods changed by pressurizing except rice and soy bean. The texture of potato and sweet potato turned to pliable and the sweetness of sweet potato increased. Taproot vegetables increasd in transparency and became pliable. The transparency and sweetness of the fruits increased. Pear and persimmon softened. The color of meats was tinged with white and their hardness increased. Gelatinization in potato starch was not observed. Pressurized Japanese radish absorbed more sodium chloride than controlled one. The browning rate of potato was accelerated by pressurizing. From these results, it is suggested that hydrostatic pressure will become one of the useful way for new food processing or cooking.

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Bacillus natto was cultured in the chemically defined liquid medium which contain various amino acids as nitrogen source, and effects of amino acids on the formation of pyrazines were examined. The amino acids which are related to glutamic acid on metabolism, L-glutamic acid, L-aspartic acid, L-arginine and L-proline, promoted the best growth. Yields of pyrazines produced in the culture broth were not always parallel to cell growth. In the case of L-serine, L-aspartic acid, L-alanine and ammonium citrate, whole pyrazines were yielded about 10mg/l and above, and mostly consisted of tetramethylpyrazine. Pyrazines which have a characteristic side chain corresponding to the amino acid present in the medium were not detected.

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Multi-biting test of liquid samples prepared from rices by the specified method was carried out for investigating their physical properties correlated to the eating qualities of cooked rices. Differences in physical properties correlated to the eating qualities of glutinous and nonglutinous rices could be estimated by this method. Three pairs of rices from IRRI (lnternational Rice Research Institute) of which differences in physical properties correlated to the eating qualities cannot be explained by conventional physical measuring methods were submitted to this multi-biting test. Differences in the physical properties correlated to the eating qualities of these three pairs of rites were estimated clearly by this method.

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free and protein-bound amino acids and extractable 5'-GMP in fruit-bodies of Shiitake Mushroom (Lentinus edodes Sing.) grown on artificial bed-blocks examined. (1) The crude protein content was 25.9%and the carbohydrate was 67.0%. (2) The total free amino acid content was 1665mg/100g dry weight. In free amino acids component, glutamic acid was the dominant and was 385.9mg/100g dry weight. Free amino acids content per dry weight decreased slightly with the growth of fruit-body. (3) Among the protein-bound amino acids, glutamic acid was the major compound, while methionine and cysteine were minor ones. (4) The amount of 5'-GMP extracted from whole of matured fruit-bodies was 312.8mg/100g dry weight, and that in the cap of fruit-bodies was amounted to 2.6 times compared with the stem.

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Using the technique of gas chromatography equipped with FPD, concentrations of 7 isothiocyanates, iso-propyl isothiocyanate (itc), sec-butyl itc, n-butyl itc, allyl itc, 3-butenyl itc, 3-methylthiopropyl itc and β-phenethyl itc, were determined. In these cases, the formulas, y=ax^b, were established in each case. Where x are concentrations of these isothiocyanates, y are [peak areas of these isothiocyanates/that of internal standard (phenyl isothiocyanate)]x100, a and b are constant number. Therefore, simultaneous determination of 7 isothiocyanates in natural material hydrolysate became to capable.

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Phenolic compounds in Katsuobushi was determined by a high-performance liquid chromatography (HPLC). An assay solution was prepared as follows; 5g of Katsuobushi powder were extracted with 60ml of 40 (v/v) ethyl alcohol for 15min at room temperature. The extract was filled up to 100ml with 40%(v/v) ethyl alcohol and was filtrated with 0.2μm filter. Determination was performed using Shimadzu LC-6A under the following conditions; A column pipe (4mmφ×15cm)was packed with ODSH (Shimadzu Techno-Research)and eluted with methanol-water (adjusted to pH 2.1 with phosphoric acid)[15:85, v/v]at a flow rate of 0.8ml/min. Column temperature was 55°C. Column effluents were monitored at 268nm. This method will ensure the determination of phenolic compounds in Katsuobushi with 2-3% of coefficients of varience and 96-99% of recovery. 2, 6-Dimethoxyphenol was the most predominant among 3 kinds of phenolic compounds, and the concentration of the phenol was 50μg/g. The phenolic compounds gradually increased in number as well as in amount with the advance of the smoking process, and reached saturation at the middle of smoking process.

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The contents of potassium, sodium, calcium, magnesium, phosphorus, iron, copper, zinc, manganese, cadmium, lead, arsenic and mercury in 48 species (56 samples) of wild edible mushrooms and 1 species (1 sample) of cultivated mushroom growing in soil, collected and purchased mainly Kanto, Chubu and Tohoku districts from 1979 to 1986 were determined. The results were as follows; K: 1.1-5.4%, Na: 15-170mg/100g, Ca: 2-89mg/100g, Mg: 8-161mg/100g, P: 165-2028mg/100g, Fe: 3.4-547.0mg/100g, Cu: 0.1-41.6mg/100g, Zn: 0.7-20.8mg/100g, Mn: 0.4-13.3mg/100g, Cd: BDL(Below Detectable Level)-86.05 ppm, Pb: BDL-20.26ppm, As: BDL-93.25ppm and Hg: BDL-6.67ppm in dry basis, respectively. There were differences in the mineral contents among the different species of edible mushrooms. Some characteristics were found in the mineral contents of the samples belong to the same species.

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Application of hydrochloric acid extraction procedure for determination of inorganic elements (K, Mg, Ca, Zn, Mn, Cu, Fe and P) in animal foods (raw skipjack, boiled and semi-dried whitebait ("shirasuboshi"), boiled and dried sardines ("niboshi"), loin of pork and pig liver) was described. Potassium, Mg, Ca, Zn, Mn, Cu and Fe were determined by atomic absorption spectrophotometry (AAS) and P was determined by vanadomolybdate spectrophotometric method. The results were compared with those obtained by dry ashing method using platinum dish or wet digestion method using HNO3-HClO4 as pre-treatment. (1) Potassium, Mg, Ca, Mn and Zn in animal foods were extracted with 1% and 3% HCl solution at room temperature (20-25°C), and Cu was extracted with 3% HCl solution at room temperature (20-25°C). (2) Iron in pig liver and "shirasuboshi" were extracted at 80°C with 3% HCl, but extraction of iron in the other animal foods was incomplete, ranged between 37 and 68%. (3) APDC-DIBK extraction of Fe, Cu and Zn followed by AAS determination could be applied to 3% HCl extracted solution as same as dry ashing or wet digested sample solution. (4) Extraction of phosphorus in animal foods with dilute HCl was incomplete, ranged between 70 and 89%.

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From a Japanese linden honey sample, trehalulose, 1-O-α-D-glucopyranosyl-D-fructose, was isolated by gel filtration chromatography, ion exchange chromatography and preparative HPLC, and was finally identified by TLC and ¹³C-NMR. Occurrence of trehalulose was confirmed in 9 nectar honey samples derived from 7 floral sources in Japan. Trehalulose contents of the honey samples ranged from 0.5 to 2.5% of total solid.

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Excretion of cholesterol into the feces increased with the feeding of pectin in rats. Filtration with an ultrafilter of a mixture of cholesterol or free fatty acids with various soluble dietary fibers (SDFs) resulted in low levels of cholesterol or free fatty acids in the filtrate. Glucose, organic acids, and water soluble fatty acids were found in the filtrate even when mixed with SDFs at physiological pH. From these results, it seems that the increase in cholesterol excretion into feces by pectin may be due to the entrapment by SDF matrix or destruction of the micelles of cholesterol or fatty acid with SDF.

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A reverse-phase high performance liquid chromatography (HPLC) was developed to separate and quantitate allyl isothiocyanate (AIT), a pungent principle of brown mustard, and cinnamaldehyde (CA), an aromatis principle of cinnamon. These compounds were extracted from ground spices with 70% (v/v) ethanol, separated on a Hitachi-gel # 3011-O by reverse-phese HPLC using methanol as a mobile phase with a flow rate of 1.00ml/min and detected by ultraviolet absorption at (190-400)nm. (1) AIT had a UV absorption maximum at 245nm and RT was 2.39min. AIT content of mustard extract (20% w/v) was 1.808±0.019mg/ml and in terms of defatted mustard, it was equivalent to 9.040±0.095mg/g. (2) CA had a UV absorption maximum at 286nm and RT 2.80min. CA content of cinnamon extract (20% w/v) was 6.810±0.014mg/ml, and in cinnamon, it was 34.050±0.070mg/g.

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