The rheological properties of four kinds of heated meats, broiler, beef, pork, and mutton, have been examined by stress-relaxation experiments. The elastic modulus and the viscosities of the heated meats except broiler increased as the heating temperature increases. Those values of broiler increased slightly with heating temperature and dropped at 100°C. The long relaxation times had the minima at ca. 50°C of heating temperature, whereas the short relaxation times did not depend on the heating temperature.

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The near infrared reflectance method (NIR) was applied to determine the total nitrogen content of green tea. The infrared spectrum of green tea showed a charactaristic pattern in the wavelength region of 1100 to 2500nm comparing with the data of dried laver, wheat and soybean reported, previously. Especially, the specific spectrum pattern was indicated in the region of 2000 to 2220nm. Among about 30 bands obtained in the spectrum of green tea, some characteristic absorption bands were found. A high positive correlation was obtained between the intensity of absorbance using the second derivative (dd²log (1/R)) spectra derived from the absorption band of protein and the total nitrogen content of green tea. By the way, a stepwise multiple linear regression analysis using the second derivative selected the four wavelengths in the order of 2018, 1978, 1942 and 1333nm. The high relationship between chemically analyzed total nitrogen and the values estimated by the regression was obtained, and the correlation coefficient and the standard error of estimation are 0.995 and ±0.072, respectively.

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The improved reverse system (MAK system) of desalting sugar liquid with ion exchange resin has reported in our previous paper. The purpose of this investigation was to determine the head loss with each ion exchange resin layer which was scheduled to use MAK process, by using a experimental apparatus, in order to draw up the industrial plan. On the basis of these experimental data, empirical formula for calculating the head loss in each resin was determined. One might conclude that the head loss with strong basic anion exchange resin layer in M or A tower, was not troublesome. Since the functions of all comercial weakly acidic cation exchange resins (K tower), have not proved consistently successful in both physical (head loss) and chemical properties (Na⁺ leak), it was thought advisable to investigate the excellent synthetic method of weakly acidic cation exchange resin for applying MAK process sartisfactorily. An excellent method was required for the preparation of good quality resin having high capacity, and high ion exchange rate. Having been done the development of this high quality resin which was manufactured by the Mitsubishi chemical industries Co., Ltd., in collaboration with us, the head loss problem is now settled in MAK process.

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Clostridium thermosaccharolyticum is generally believed to be obligate thermophile. However the type strain (ATCC 7956) and 2 of 9 strains of the species isolated from spoiled canned foods grew well from spores with abundant gas productions in PE-2 medium (10ml of solution containing bactopeptone 0.5%, yeast extract 0.5%, L-cysteine hydrochloride 0.05% and agar 0.15% was placed in a screw-capped tube having an outside diameter of 16mm and a length of 150mm, containing 3 to 4 dried peas and 0.1g of calcium carbonate, and then the tube was autoclaved for 20min at 121°C) after 20 days at 29°C. Two strains in comminuted asparagus and 5 strains in comminuted baby clam grew with abundant gas from spores after 60 days at 30°C. Thus, the bacteria is not obligate but facultative thermophile. A possible cause of the canned food spoilage owing to the growth of C. thermosaccharolyticum might be under processing rather than exposure to unusual high temperature after thermal processing.

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Pathway of acetoin formation in vinegar making was examined using Acetobacter aceti IFO 3283 strain. The enzymes participated in two metabolic pathways on producing pyruvic acid from malic acid were purified. The purified enzymes reacted on their substrates. Reaction products were analyzed qualitatively by thin layer chromatography. As the results, it was found that this strain had two pathways for acetoin formation. The one is the metabolic pathway to pyruvic acid from malic acid by malic enzyme. The other was that to oxaloacetic acid from malic acid by malate dehydrogenase and to pyruvic acid from oxaloacetic acid by oxaloacetate decarboxylase.

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A conductometric flow injection analysis system for measuring sugar content in food was constructed and several component of this system were investigated. The controlled-current four-electrode method was used for conductance measurements, and then the cell constant of this system was not affected by flow rate (0-5ml·min-1). The most preferrable conditions for optimum operation of the system were as follows: mixing coil length 80cm (i. d.=0.8mm), injection volume 0.68ml, flow rate 2.3ml·min-1. Over the range of 5 to 30% (w/w), the linear response was obtained and the coefficient of variation was 0.20% at 20% (w/w) sucrose for 10 successive assays. The measuring time was about 3min for each of these assays. The sugar content in citrus juice estimated with this system agreed with that obtained from phenol-sulfuric acid method within an error of 0.20% (w/w).

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An accurate determination for naringinase activity by HPLC and modified DAVIS'method was studied. The authors recommended the HPLC method for the purpose as it gave an accurate amount of α-rhamnosidase as naringinase activity. In comparison with the conventional methods, modified DAVIS'method and remodified one by OKADA, the new method gave the reasonable results, in which a separative analysis of naringinase was established.

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California, Davis, California 95616, U.S.A. Ethanol vapor treatment on the tree to intact fruit of Japanese persimmon cv. 'Hiratanenashi' removed its astringency quickly and induced flesh darkening within 3 weeks. Ethanol treatment did not promote the browning reaction of fruits stored at 1°C. The crude polyphenol oxidase (PPO) preparation obtained from the mesocarp as an acetone powder was much more active when extracted at 24° than when extracted at 5°C. of the 5 common substrate polyphenols tested, 4-methyl catechol was oxidized most rapidly by the enzyme. PPO activity increased sharply just after the loss of astringency coincidentally with the initial appearance of darkening in the calyx end. This high activity was maintained while the darkening was progressing throughout the entire flesh.

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Limonoids were isolated from the seeds and flesh of `banpeiyu' (C. grandis Osbeck). The extracted limonoids were separated by thin layer chromatography and purified by acetone. The determination of isolated limonoids was made by a high performance liquid chromatography (HPLC). In the seeds of `banpeiyu', 600ppm of nomilin, 300ppm of limonin, 150ppm of deoxylimonin and 70ppm of obacunone were detected. It was shown that the nomilin content was higher than the other limonoids in the seeds. In the flesh of`banpeiyu', 3.1ppm of limonin, 0.95 ppm of nomilin, 0.14ppm of deoxylimonin and 0.02ppm of obacunone were detected. The major limonoid was limonin in the flesh and nomilin in the seeds. The seeds contained a large amount of limonoids, showing about 260 times as much as that of the flesh.

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The relationship between four fermentation conditions in pastry production by the sugar containing sponge dough method and flavor substances in products were investigated using the experiment of orthogonal L8 design. The four fermentation conditions were sponge dough mixing temperature, sponge dough fermentation time, dough mixing temperature and floor time. The flavor substances in the products were analyzed by a headspace gas chromatography. Alcohols and acetone in the products were increased with sponge dough fermentation time. Aldehydes in the products were not affected by the four fermentation conditions. The peak regarded as acetoin was increased with sponge mixing temperature and sponge dough fermentation time.

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