Following the previous report, we studied on various conditions of temperature and relative humidity for desirable continuous drying process using a model appratus. The chemical components drying process using a model appratus. The chemical components and physio chemical characteristics of dried skipjack (not moulded) produced by continuous processes were also compared with usual products.
1) To remove rapidly the water in the skipjack in the earlier stage of drying, the supply of more hot air was essential, but after 20 hours operation the temperature and relative humidity must be kept approximately 70-80°C and 50-60% respectively.
2) The time required to produce the product by continuous process was within 80 hours and drying rate was maintained comparatively on the constant level if appropriate programmes were selected.
3) The difference of 5'-IMP content of dried skipjack between cotinuous and usual method was not detected, but rapid discolouration on drjed product by continuous process which didn't use smoke as usual process was observed. So we suggested the protective effect of smoke from oxidation of skipjack.
4) The consideration of results related to hardness, fracturability and cohesivenss showed that diffusion of interior water was carried out more easily at lower temperature (60-70°C) and characterisics of products produced under high temperature and low humidity were more fragile.

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In order to evaluate the quality of canned tomato juices in long-term storage, carbonyl compounds were investigated qualitatively and quantitatitively. They were converted into 2, 4-dinitrophenylhydrazone and separated by thin-layer chromatography. 3-Deoxyglucosone, 3-deoxypentosone, hydroxymetyl furfural (HMF) and furfural were identified as dominant carbonyl compounds. Formation of furfural proceeded also at room temperature during storage, whereas HMF was formed apparently at higher temperature. On the volatile carbonyl compounds fifteen peaks were detected on gas chromatograms injected with 2, 4-DNPs derivatives of the distillate and nine n-alkanals, three methylalkylketones and furfural were estimated.

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The possibility of furfural concentration as an index for quality evaluation of canned tomato juices was investigated. After distillation under reduced pressure and extraction with ethyl ether, furfural was determined satisfactorily by colourimetry using aniline. Formation of furfural proceeded remarkably at higher temperature storage and also at 20°C. On the other hand, hydroxymethyl furfural formed noticeably only at 55°C. The relationship between furfural content and organoleptic evaluation was discussed. When furfural contents exceeded 100μg/l., a panel observed a difference in quality compared with that of controls at a significance of p<0.05 in triangular test. This value reached after four months storage at 37°C and about four years storage at room temperature.

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Antioxidatlve activities of twelve flavonoids were examined. Gossypetin and herbacetin having OH at 8 position of flavonol showed remarkable antioxidative activity against autoxidation of lard. Although quercetin derived by removing OH at 8 position of gossypetin inhibited autoxidation of lard, its antioxidative activity was reduced about 1/3 as compared to gossypetin. Furthermore, kaempherol derived by removing OH at 3 position of quercetin showed hardly antioxidative actity. Both naringenin and hesperetin having no reducing power for DPPH did not inhibit autoxidation of lard.
Synergistic effect was recognized in combination of nine flavonoids with melanoidin and six flavonoids showed synergistic effect on d-δ-tocopherol. In combination of two kinds of antioxidants selected from gossypetin, d-δ-tocopherol and melanoidin, gossypetin and melanoidin showed the most effective inhibition on the oxidation of lard. However, the combination of gossypetin, d-δ-tocopheral and melanoidin extended induction period of lard to three times higher that of gossypetin and melanoidin.

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In order to obtain data about a moistureproof packaging design for spray-dried Citrus unshiu juice, the rate of adsorption of moisture on the powder with or without cover of the plastic films was examined by a dish method at 25°C and 92% relatve humdity. The adsorption isotherms obtained were conformed to the PAIN equation.
The rate constant of moisture adsorption K for the powder was 310×10^-5 to 546×10^-5 hr^-1, whereas that K' of the powder covered with film was 1×10^-5 to 36×10^-5 hr^-1. Both K and K' became greater with decreasing the content of pulp, and K' became greater when film having higher moisture permeability coefficient Q was used. The plots of log K' were expressed as a straight line.
An empirical equation, log K'=2 log K+log Q, was derived from the experimental data.

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Fractions of lipid and protein were separated from the proteolipid which had been isolated in the previous study. Determination of the lipid moiety showed that the major components were phospholipids, mainly composed of phosphatidylcholine, phosphatidylethanolamine, phosphatidic acid and a small amount of glycolipid. The protein moiety contained more hydrophilic amino acids and less acidic amino acids comparing with the amino acid composition of soybean globulin. From these results, the interaction between the lipid and the protein was supposed to be due to hydrophobic and electrostatic bonds. The protein moiety was separated to two components by gel electrophoresis and had two N-terminal amino acids of alanine (major) and glutamic acid.

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Effects of concentration, pH-value, caffeine content and temperature of tea infusion on the degree of creaming (turbidity) were examined quantitatively.
As it was observed that creaming was markedly decreased when a tea infusion was incubated with tannase, effect of tannase-treatment on the creaming of infusion was examined in detail under various conditions.
It was found that decrease of turbidity was in close connection with liberation of gallic acid from polyphenols, and the infusion (1.8g/100ml, 4ml) which was incubated previously with 100 units of tannase (1ml) for 1hr at 50°C was scarcely turbid by cooling at 2°C.

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The purpose of this study was to establish a practical method for the determination of the added shortenings of breads served for school lunch. In the range of 0 to 6% shortening to flour, the linear relationship was found between the amounts of added shortenings and the fats contents of the breads analyzed by the acid hydrolysis method. By use of the regression line induced, the average amount of added shortenings was estimated to be (5.3±0.9)% to flour for 17 school lunch breads produced in Nagano State.

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Ammonium sulphate and urea were investigated for the purpose of developing new standard samples instead of hippulic acid on Ncorder method, which is based on Dumas method.
(1) It was found that urea can be used as a standard sample instead of hippuric acid on Ncorder method.
(2) Using urea as a standard sample, the Ncorder method were compared with those of Kjeldahl method for several food stuffs.

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