Kiwifruit (Actinidia chinensis PLANCH. c. v. Hayward) was grouped into four groups based on its fruit hardness after storage at 4°C for three months. Contents of various components in press juices prepared from the four fruit groups were determined. There was no significant difference in the contents of sugars, total phenols, ascorbic acid and minerals. However, the contents of total nitrogen, organic acids (malic and quinic acids), soluble protein, and free amino acids (total and individual amino acids such as aspartic acid, glutamic acid, arginine, threonine, and alanine) were closely associated with the degree of hardness. Several proteins with different molecular weights were isolated from the soluble protein fractions in each group by Sephadex G-100 gel filtration. The main fraction (MW; 13000) which occupied 62-70% of the total proteins was commonly detected among four groups, and noticeable difference in the amino acid composition was not observed.

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Differences in physical properties correlated to the mouthfeel of agar and gelatin gels were investigated by using multi-point mensuration under the multi-biting test.This test is a combination of multi-biting and multi-point mensuration methods already reported. An underlying principle of the multi-biting test for solid is to detect very smalland very shortand very shortphysical deformation or break down of gels compared to the usual measuring method. Precise analysis of differences in physical properties of agar and gelatin gels is also expected by using the multi-biting test at various deformation ratio (multi-point mensuration). Apparent hardness and apparent springiness characteristics and breaking properties of various agar and gelatin gels could be compared by the progress curves betwee biting ratio (10-50%) and positive work load of a plunger (+A, g. sec) of the multi-biting test. A gradient of linear correlation between biting number and cumulative total positive work load of the plunger, and a ratio of positive work load of the plunger of tenth bite vs that of the first bite in the multi-biting test were useful parameters to analyze physical properties of both gels. Physical properties of both gels also conveniently estimated by comparing several parameters of the multi-biting test measured at 30% biting ratio.

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Total lipids were extracted from four varieties of domestic rye grains, and their lipid class compositions, the component fatty acids and sterols were investigated. The yields of the total lipids were 1.6-1.9%. The neutral lipid fraction usually amounted to about 70% of the whole, in which triacylglycerol was predominant. The ratio of the glycolipid and phospholipid fractions was approximately 1:1.4; the principal lipid classes were diglycosyldiacylglycerol, monoglycosyldiacylglycerol and cerebroside in the former group, and phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol and lysophosphatidylcholine in the latter one. The main fatty acids in nine lipid classes were generally linoleic, palmitic, oleic and linolenic acids in the decreasing order, except for acylsterol, in which the most abundant one was palmitic acid. The relative proportions of linoleic acid were 55-60 % in triacylglycerol, 65-79% in two glyceroglycolipids and 41-68% in phospholipid classes. Seven types of 4-desmethylsterols were detected, among which sitosterol and campesterol, particularly the former one, were predominant in neutral and polar sterol lipids. No significant differences were recognized in the chemical compositions of the rye grain lipids among the varieties harvested in Hokkaido, Japan.

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The characteristics of Jabara and Yuzu were examined in connection with the qualities oftheir juices produced by using three juice extractors such as a hand press extractor, a rotarypress extractor and a In-line extractor. The results were as follows; (1) The fruit weight ofJabara was 1.2-1.7 times that of Yuzu. And Jabara fruit was seedless, but Yuzu had27-28 seeds per fruit. (2) The yield of Jabara juice was apparently higher than that ofYuzu juice. That is, the yield of Jabara juice from the rotary press extractor and the In-lineextractor were 27.5-30.1% and 32.2-41.7%, respectively and those of Yuzu juice were 12.3-14.3% and 8.8-10.2%, respectively, (3) The soluble sugar content of mature-yellowJabara juice was 3.15-3.21%, which was the highest value, and the total contents of glucoseand fructose reached about 50% of the total soluble sugars. In mature-yellow Yuzu juice, the acidity showed maximum content (5.69%), and more than 85% of the acidity was citricacid. (4) The pectin content in Yuzu juice from the In-line extractor was 4- to 5-fold inmature-green fruit and 70- to 100-fold in mature-yellow fruit higher than those of Jabara, respectively. (5) The oil contents in Jabara and Yuzu juices from the rotary press extractorwere 2- to 5-fold higher than those from other extractors. (6)The major volatile componentsof Jabara and Yuzu juices were terpene hydrocarbons such as myrcene, d-limonene andγ-terpinene. Myrcene was more than 40% in Jabara juice, and d-limonene was about 80%in Yuzu juice.

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Dextransucrase production of Streptococcus bovis No.148 and leucrose production by S. bovis dextransucrase were invesitigated. S. bovis could produce dextransucrase not only on a sucrose medium but also on a glucose medium. Carbon dioxide was essentially required for the enzyme production. Influence of temperature, pH, metal ions, sucrose concentration, and fructose on the leucrose production was examined. In this study, the enzyme prepared from a glucose medium and purified by a Sephadex gel adsorption method was used. Leucrose production was little affected by reaction temperature from 20°Cto 40°C, and the leucrose yield for consumed sucrose was in the range of about 25 to 27% in a reaction mixture with 5% sucrose. The yield of leucrose was maximum at pH5.5 which is optimum pH for the function of S. bovis dextransucrase, and gradually decreased by shifting the pH to both sides. Leucrose production was stimulated by Ca²⁺, and slightly depressed by Mn²⁺. The total yield of leucrose was increased with increasing sucrose on centration up to 8%, but the yield for consumed sucrose was maximum on the reaction mixture of 2% sucrose. The yield of leucrose was remarkably increased with increasing fructose added to the reaction mixture, on the other hand, dextran production was extremely depressed.

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In order to examine a role of added sucrose in texture of Chinese style dried pork, "nikukan", changes in the weight of sliced pork during drying and shear force values after drying were measured on the addition of various concentrations of sucrose or glucose. Stiffness of obtained dried pork decreased with an increase of the sugar concentration and its decrease was significant by sucrose. When sliced pork was dried at 50°C in the presence of various concentrations of sucrose or glucose, the weight of sliced pork decreased according to a first order reaction rate. A plot of the logarithmic rate constant versus the initial molarity of sugars give a straight line. The slope of the line for sucrose was steeper than that for glucose, indicating that sucrose was more effective than glucose to depress the drying rate of sliced pork. On the other hand, when a suspension of myosin B was heated in 0.16 MKCI at pH5.5 and 50°C, its turbidity increased rapidly and reached a maximum value at the very early stage due to aggregation of myosin B. Addition of sugars depressed both the rate and the maximum value of turbidity. Such effect of sucrose was more pronounced than that of glucose. All the above results suggested that sucrose (added to sliced pork) contributed to softening of dried pork by drying uniformly the tissue due to retarding of its drying rate as well as by preventing muscle protein from excessive aggregation.

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A stevioside hydrolyzing enzyme was purified from raw soy sauce by a series of column chromatography and found to be homogeneous on polyacrylamide gel electrophoresis. The molecular weights estimated by gel filtration and SDS-polyacrylamide gel electrophoresis were 184000 and 90000, respectively, suggesting that the enzyme was consisted of two identical subunits. The optimum pH for the enzyme was about 5.0, being stable below 5.O at 4°C for 18h. The optimum temperature was about 55°C, being stable up to 50°C for 10min. The enzyme activity was inhibited by AgNO₃, CuCl₂, PbCl₂, HgCl₂, FeCl₃, AlCl₃, SDS and p-chloromercuribenzoate. Specificity studies for substrates indicated that the enzyme was specific for β-configuration of sugars and prefered β-1, 2 glucosidic linkage, suggesting that the enzyme was β-glucosidase (β-D-glucoside glucohydrolase, EC 32.1.21). The apparent Michaelis constant of the purified enzyme was 9.71mM for stevioside.

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Soybean seeds were separated into seed coat, hypocotyl and cotyledon to estimate removal efficiency of its undesirable taste by hot water soaking. The largest amount was extracted from hypocotyl and it was 53% of the control (glycosides prepared from 70%- EtOH extract from hypocotyl). Therefore, the hot water soaking seemed to be a simple and effective way to reduce the undesirable taste without dehulling and dehypocotyling processes. From TLC and HPLC patterns of glycoside components extracted from each part by 70% ethanol extraction and by hot water soaking, larger quantity of saponin A group, which has stronger undesirable taste than others, was detected in hypocotyl than in the other parts. Saponin Aa and Ab, which are the major components of saponin A group and have the strongest undesirable taste, were mainly detected in hypocotyl. Furthermore, more unidentified components (U1 and U2) and more saponin Aa and Ab were extracted by this method even than by 70% ethanol extraction, showing effectiveness of the hot water soaking on removal of the undesirable taste. The unidentified component U1 was found to be glycitein 7-β-O-glycoside and U2 to be daidzin through determination using TLC and HPLC after fractionation by Sephadex LH-20 gel permeation chromatography.

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Limonoids in seeds of Yuzu (Citrus junosSieb. ex Tanaka) were extracted with Trisbuffer (pH8) and analyzed by high performance liquid chromatography with a UV spectrophotometer. Yuzu seeds containedall of the major limonoids commonly found in other citrus. Limonin was predominant, 32% of the total limonoids, followed bynomilin, ichangensin and deacetylnomilin.Small amounts of acidic limonoids such as nomilinic acid deacetylnomilinic acid, isolimonic acid and obacunoic acid, were also present. Ichangensin present in Yuzu appears to be inherited from Ichang Chie (C.ichangensis), supporting the report thatYuzu is a hybrid of Ichang Chie.

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Three methods, i.e., immunological method, thin layer isoelectric focusing and high performance liquid chromatography (HPLC), for the identification of the unheated meat species were compared. Three methods were species-specific and immunological met hod was especially high sensitive. However, the hen antiserum reacted with duck cut and yolk of immunological method. Horse meat and chicken mixed in chopped meat could not be identified by thin layer isoelectric focusing. Horse meat could not be identifie d by HPLC. HPLC method was able to analyse the mixed ratio of beef and pork. Eleven commerc ial chopped meats, and 4 commercial and l home made hamburger patty were examined. As the result, one chopped meat labelled as containing only beef and one hamburger patty were shown to contain horse meat by immunological method.

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α-D-Mannosidase of kiwifruit was purified from flesh by ammonium sulfate fractionation and column chromatography on DEAE-cellulose, hydroxylapatite, Sepharose CL-6B and Con A-Sepharose 4B. The purified enzyme was almost homogeneous on disc gel electr phoresis. Its molecular weight was estimated to be 86000 by gel filtration and 83000-85000 by SDS-polyacrylamide gel electrophoresis. The pH optimum was found to be 5.0-5.5, The enzyme was stable in the pH range of 6.5-7.5, and up to 55°C during 10 min incubation. It showed Km value of 6.7mM for p-nitrophenyl α-D-mannoside. Its activity was stimulated by Zn²⁺. It catalyzed the hydrolysis of ovalbumin glycopeptide and yeast mannan.

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Under aerobic condition, starter lactic acid bacteria could not inhibit the growth and enterotoxin production of Staphylococcus aureus in the fermented sausage. But, by the combination of starter cultures and anaerobic incubation using nitrogen gas atmosphere or vacuum-packaging, S. aureus was markedly inhibited and no longer could initiate growth even when the sausages were exposed to aerobic condition. When the inoculum level of S. aureus was 10 5 or 10 6 cells/g, enterotoxins were not detected in the sausage.

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