(1) Stimulative effects of various miso and soy sauce for acetic acid production were revealed when acetic acid bacteria including Acetobacter No.2 strain(accepted from National Institute of Fermentation Technology, Ibaraki-ken), Acetobacter aceti IFO 3281 and M-1 strain isolated from vinegar mash were employed as starter. Among the tested materials including miso and soy sauce, when supplemented to the basal medium, no salt soybean miso had the highest stimulative effect as same level of yeast extract. (2)Stimulative substances in no salt soybean miso were separated into an acidic fraction and a neutral fraction on a chromatography employing Amberlite IR-120(H⁺)and IR-4B(OH^-). The basic fraction, however, showed slightly stimulative effect. (3)Most effective substances in neutral fraction were considered to be composed of glycerol and sugars as the results of the bioautography and gaschromatography. Stimulative effect of the acidic fraction was suggested to due to the organic acids such as lactic and succinic acid from the organic acid components of the acidic fraction.

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The influences of headspace volume, pasteurization temperature, pasteurization time and storage temperature on the quality of Satsuma mandarin(Citrus unshiu Marc.)juice were investigated. The reconstituted juices(12°Brix)were packed into Tin Free Steel cans(250ml)under the following conditions: headspace volume, 0-20ml; pasteurization temperature, 60-93°C; pasteurization holding time, 0.5-10min. The final juice products were stored at 20°C or 37°C during 6 months, and tested periodically for the changes of browing, ascorbic acid, 5-(hydroxmethyl)-2-furfra 1(HMF)and sensory evaluation. Headspace and storage temperature rather than pasteurization temperature and time affected the juice quality. With the rises of headspace volume and storage temperature, ascorbic acid and sensory score rapidly decreased while browning(O. D. 430nm)and HMF gradually increased. From these results, it was demonstrated that headspace and storage temperature play an important role in keeping the quality of canned Satsuma mandarin juice.

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Apples cv. Starking Delicious are sensitive to cold temperature and apples cv. Ralls Janet are less sensitive to cold temperature. To make clear the mechanism of the chilling injury from the level of molecular species, the molecular species of phosphatidylcholine in the fruits of both cultivars were examined. As the results, the phosphatidylcholine of cv. Starking Delicious and cv. Ralls Janet was fractionated into 10 bands and 6 bands, respectively, by argentation thin-layer chromatography. The fatty acid composition of each band of phosphatidylcholine differed among harvest years in Starking Delicious. The each band seperated by argentation thin layer chromatography contained one, two or more kinds of molecular species, respectively. The fatty acid composition of each band of phosphatidylcholine in the fruits were different between both cultivars. The numbers of molecular species in both cultivars decreased after cold storage, especially those containing unsaturated fatty acids.

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Winged bean was soaked for 18hr in the solutions of sodium bicarbonate, sodium chloride and cellulase and macerating enzymes prior to cooking. These presoaked beans were cooked with and without pressure. The enzyme treatments hardly showed any effects on cooking time to get soft seed by both cooking methods, but presoaking in sodium bicarbonate solution was most effective on both cooking methods. 67% of winged bean protein was extracted with water, and the aqueous extract was processed into curd with calcium sulfate or glucono-δ-lactone. Solid curd was not formed under the same conditions manufacturing soybean curd(Tofu). The aqueous extract of soybean could be replaced up to 30% by the winged bean extract on manufacturing Tofu.

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Chemical composition of the Enso mucoid of Shokuyo-Anatsubame(Collocalia fuciphaga)were investigated, in particular saccharides and amino acids. (1) It contained moisture 14.3, saccharides 27.5, N9.3, ash 4.8, Ca 0.693, P 0.004 and S 0.70%. (2) A fraction(F-Ia)1.9g was obtained from 10g of the material by extraction with boiling-water and fractionation with gel filtration. Its molecular weight was estimated to be 10000O-500000. The ratio of the content of saccharides (reducing saccharides)and that of proteins was 1:2.4 in F-Ia. (3) PPC revealed that the saccharide components of the fraction(F)consisted of galactose, mannose and fucose; the composition of which analyzed by GLC was 84.7, 10.5 and 4.8%, respectively. (4)Amino acid analysis showed that the fraction(F-Ia)conntained aspartic acid 11.7, serine 10.7, valine 10.2 and threonine 10.1%.

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In the previous report, emulsifying capacity of yeast protein isolates prepared with three different methods(Yeast protein isolate I, II, III)was studied in comparison with those of soy protein and caseinate at various pH's, ionic strengths and leicthin contents(%). In the present study, emulsion stability of these three yeast protein isolates was compared with the results of previous reports and the particle sizes of these emulsions were measured with a microscope. Emulsion stability of yeast protein isolate I was far superior to that of soy protein or caseinate, especially in the acidic and alkaline region. However, yeast protein II and III gave low emulsion stabilities, which were similar to those of soy protein or caseinate. It was suggested that emulsifying properties of the yeast protein isolates were largely influenced by preparation methods of the protein. The particle sizes of the emulsions which have good emulsifying properties were smaller than those of poor emulsions and yeast protein isolate I had the smallest particle sizes.

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Compound lipid fractions separated from total lipids in ordinary meat, red meat, skin, liver and viscera(except liver)of horse mackerel, Trachurus japonicus were examined by means of silicic acid column chromatography(SACC), thin layer chromatography(TLC)and gas chromatography (GC). Total lipids were separated into neutral and compound lipid fractions according to the procedure of CARTER et al. The compound lipid fraction content(g/100g sample)in liver was the highest among five parts above mentioned. Compound lipid fractions were separated into individual lipids by SACC and TLC, and their main components were phosphatidyl choline(PC), phosphatidyl ethanolamine (PE), cardiolipin(CA), phosphatidyl serine(PS)and sphingomyelin(Sph). The difference of each compound lipid content(%)between ordinary and red meat was small and the difference of the above content between liver and viscera was also small. However, serious difference was observed between meat(ordinary and red meat)and viscera(liver and viscera)in each compound lipid content, especially PC and CA contents. Fatty acid compositions of each compound lipid were studied by GC and about 30 kinds of fatty acids were identified. Main fatty acids were 22:6 and 16: 0 acids in PC, 22:6 and 18:0 acids in PE, 22:6, 18:1 and 16:0 acids in CA, 18:0 and 22:6 acids in PS, and 16:0, 18:1 and 22:6 acids in Sph. Main fatty acid compositions of each compound lipid in liver and viscera were different compared with those in other three parts.

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By Sephadex LH-20 column chromatography through stepwise elution with 22-99% methanol, banana tannin components were fractionated as nine peaks, where I, IV, V and IX were the major peaks constituting 44.6, 12.3, 11.2 and 13.2% of total absorbancy, respectively, and the others were minor peaks. Some physicochemical properties of the components of fractionated peaks were determined. The effect of these peak components on oxidative browning of dopamine catalyzed by bananapolyphenoloxidase(PPO)was studied. Further, the effect of some phenolic substances on the browning was described. Resorcinol and phloroglucinol increased the rate of banana PPO catalyzed oxidation of dopamine, although, neither was found to be banana PPO substrates. p-Hydroxybenzoic and cinnamic acids were non-competitive inhibitors, whereas, protocatechuic and o-coumaric acids responded as competitive inhibitors. The sequence of reactions occurring during oxidative changes of dopamine by banana PPO was elucidated through study of the absorption spectra.

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A special method for temperature correction was developed for practical determination of sugar content in Citrus juice by means of our new method based conductometry. Accordingto our devised method, the sugar content could be estimated from Eq. (1) at the temperature range 5-35°C. Eq. (1) could achieve not only the temperature correction but also the correction of experimental errors due to the change of KCl concentration:
Sugar (w/w%)={A·K_b(0.12t+3.96)/0.12t_b+3.96-B}K+0.309t+58.05 (1)
where, k and k_b are the conductivities(Sm^-1)of KCl added juice at t(°C)and of blank solution at t_b(°C), respectively; A and B are the correction factors of KCl concentration and each was approxi-mated by the seven straight lines for the range of 5° to 35°C. The availability of Eq. (1) was evaluated under the different conditions of temperature and of KCl concentration: the coefficent of variation was about 1%. The devised method including Eq. (1) will make it ease to realize an automatic temperature correction.

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