Production of dairy flavors by microbial lipase modification upon milk fat was investigated. Fatty acids released from whole milk, cream and butter by various lipases were converted to methyl esters and then analyzed by gas chromatography. The lipase treated products were also organoleptically evaluated. The free fatty acid profiles produced by microbial lipases showed a relatively small difference, while a great difference was observed between microbial and animal lipase (pregastric esterase, pancreatic lipase). Organoleptically each lipase developed characteristic flavor. The microbial lipase from Candida cylindracea nov. sp was selected as one of the most suitable one for producing dairy (especially creamy-buttery) flavors. The following investigation was made on the behavior of this lipase. Different fatty acid profiles were obtained from three substrates; consentrated milk, cream and buffer. Each profile resembled to that of free fatty acid in each untreated substrate. Fatty acid profiles produced at different stages of hydrolysis showed a little difference. In the case of C.cylindracea lipase a lag phase in hydrolysis curve was observed in only cream among three substrates, but other lipases had no lag phase in all substrates. Through this investigation a production method of various dairy flavors in desired intensity was established by using microbial lipase.

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The heat-induced gel formability of myosin B (natural actomyosin) and washed actomysin which prepared removing main regulatory proteins (tropomyosin, troponin) from natural actomyosin, were investigated. The results obtained were summerized as follows: (1) Elastic modulus, modulus of breaking elasticity and breaking energy of the heat-induced gel obtained from washed actomyosin were superior to those of myosin B in range of 50° to 100°C, and the drop in heat-sensitivity of washed actomyosin was observed. (2) The differences of rheological properties between both proteins reflected microstructure and solubility of gels, and those were closely affected by the form of network rather than protein quantities. Changes in minuteness and regulality of network were observed at 70°C and 100°C, respectively. (3) According to NaDodSO₄-Polyacrylamide gel electrophoresis patterns, myosin heavy chain, actin and myosin light chain 2 were responsible mainly for the heat-induced gel of washed actomyosin, whereas all of the constitutire proteins were responsible for that of myosin B. In the heat-induced gel at 100°C, S-1 fraction of myosin heavy chain was detected with both proteins. It is concluded from above observations that two regulatory proteins have no effect on the heat-induced gel formability of myosin B.

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The samples used in this experiment were fresh tea leaves (S-1), grean tea (S-2), green tea prepared by heating at 130°C for 30min (S-3), corresponding to refired green tea, and green tea prepared by heating at 170°C for 30min (S-4), corresponding to roasted green tea, i.e. Hoji-cha. Crude lipids (CL) were extracted with CHCl3-MeOH (2:1), and then separated into three fractions, which were chloroform fraction (CH), acetone fraction (AC) and methanol fraction (ME), by a silicic acid column chromatography using three kinds of solvent systcms. Total fatty acid contents of CL of S-1, S-2, S-3 and S-4 were 4.0, 3.3, 2.8 and 3.0%, respectively. Fatty acid contents of all fractions showed a tendency to decrease during manufacture of green tea, and the degree of decrease in ME was slightly large compared to other fractions. In AC, the ratio of main unsaturated fatty acid (C_18:2, C_18:3) to main saturated fatty acid (C_16:0) of S-4 was a little smaller than those of other samples, but there was little difference in the ratios among other fractions.

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Three fractions (I, II and III) of pectic polysaccharides were separated from a cotyledon extract of Adzuki beans (Vigna angularis) by DEAE-cellulose column chromatography. The ratio of the amounts of I, II and III was approximately 7:4:3. Gas chromatographic analysis of the acid hydrolysates of the fractions revealed the presence of the following neutral sugars in each one: galactose, mannose, glucose, arabinose, xylose, rhamnose and fucose. Fraction I contained glucose as a major constituent (about 70%), and considerable amounts of xylose and galactose, but no uronic acid. I gave no color with iodine and was resistant to the hydrolytic action of a bacterial α-amylase; I is likely to belong to a class of hemicellulose. The molecular weight of I was estimated to be about 3×103. Fractions II and II containing about 32 and 42% of galacturonic acid, respectively, were susceptible to the action of endopolygalacturonase of Kluyveromyces fragilis. The low molecular weight products, mono- and oligogalacturonates, at a final stage of the enzymatic degradation amounted to about 20 and 43% of the total uronate contents of II and III, respectively. Judging from their susceptibility to the action of the pectic enzyme, their basic structures probably resemble those of common pectic substances which are the main components of middle lamella of primary cell walls of fruits and vegetables. The major neutral sugar constituents of II and III were xylose, arabinose and galactose.

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In the process of making dry fruit (Hoshi-gaki) from two varieties of astringent persimmon, i.e., Koshu-Hachiya and Koshu-Hyakume, changes of taste components such as soluble tannin and free sugars were examined. The samples of every drying stage were extracted with methanol and the methanol extracts were subjected to analysis of soluble tannin by the Lowenthal-Proctor method and sugars by both Bertrand method and gas chromatography. Soluble tannin and astringency disappeared in 7 days. Fructose and glucose initially decreased and then increased, while sucrose once increased and then decreased during this period. Finally sucrose disappeared after about 10 days from the beginning of sun drying. Total sugar always amounted to about 60% in dry matter through the course of drying. White powder developed on the surface of dried persimmon was consisted of fructose and glucose at the ratio of 1:3.5-4.3. Mannitol, which was previously reported and sucrose were not detected.

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Three fractions of neutral lipids, glycolipids and phospholipids were obtained from total lipids in seeds and endocarps of two cultivars("Hakuho" and "Kurakata-wase") of peaches, Prunus persica BATSCH var. vulgaris MAXIM. by mean of silicic acid column chromatography. Further, several lipids were separated from the fraction of neutral lipids by thin-layer chromatography. Fatty acid composition of the above lipids was determined by mean of gas-liquid chromatography. The results obtained were as follows: (1) In the case of two cultivars, total lipid contents were 2.2-3.6% in seeds and 0.1-0.2% in endocarps. Neutral lipid contents in total lipids were 92.8-95.0% in seeds and 47.4-48.1% in endocarps, (2) The main lipids in neutral lipids were triacylglycerol (88.6-92.1%) in seeds, and sterols (28.2-30.5%), 1.2-diacylglycerol (15.8-15.9%), triacylglycerol (12.6-12.8%) and 1.3-diacylglycerol (10.0-14.9%) in endocarps. (3) Fatty acid compositions of total lipids, neutral lipids and several lipids (sterolesters, triacylglycerol, free fatty acids, 1, 3-diacylglycerol, 1, 2-diacylglycerol and monoacylglycerol) contained in neutral lipids fraction were remarkably dif- ferent between seeds and endocarps, but were not different between two cultivars. The main fatty acids were C_18:2, C_18:1 and C_16:0 in seeds, and C_18:3, C_16:0 and C_18:2 in endocarps.

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Aiming to recycle food-processing waste into animal feeds, the effect of irradiation on the recovery of suspended solids from blood waste water treated with chitosan and it's disinfection was investigated. The wastewater was coagulated by the addition of chitosan. The coagulation was accelerated by pre-irradiation treatment, and the acceleration was maximum at around 3 Mrad irradiation. In the coagulum from blood wastewater treated with chitosan or in blood powder, the viable counts of total aerobic microorganisms (2.4×10⁶-6.0×10⁷/g) and coliforms (1.8×10⁶-3.3×10⁷/g) were decreased to undetectable levels with doses of 1.5-2.0 Mrad and 0.2-0.5 Mrad, respectively.

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The Si content in tea was assayzed by the inductively coupled plasma-atomic emission spectrometry. Before making an alkalic solution of Si, it was neccesary to remove Ca, Al, Mn and Fe in tea ash from the samples. These compounds co-preciptated with Si in an alkalic solution. The range of Si assay was 1-30μg/ml.

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