A study was undertaken to evaluate the antioxidative activities of several vegetables of Allium species. Results obtained were as follows: (1) While every vegetables of Allium species tested(Allium sativum L., A. cepa L., A. tuberosum Rottler, A. fistulosum L. var. caespitosum Makino, A fistulosum L., A bakeri Regel) exhibited apparent antioxidative activities in a linoleic model system, only A. sativum L. and A. cepa L. showed the activities against a minced pork model system. (2) A. sativum L. and A. tuberosum Rottler contained higher amounts of sulfides than others tested. (3) A larger amonut of S-alkyl-L-cystein sulfoxide was found in A. sativum L., A. bakeri Regel, A. tuberosum Rottler, A. fistulosum L. than in other samples tested. (4) Boiling or microwave heating increased antioxidative activities the vegetables of Allium species and decreased their flavor contents.

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Properties of buckwheat proteins were investigated from the standpoint of food processing, and the following results were obtained. The protein content of the 3rd flour (obtained at the final stage of crushing) was around 5 times as high as that of the 1st flour (obtained at the initial stage), and 80% of the former proteins was water-soluble. Physical properties of acid-precipitated protein (APP) from the water extract resembled those of wheat gluten. Especially, a remarkably high viscoelasticity was found in the APP from the 1st flour. The extent of the protein-protein interaction induced by heat treatment of the water extract from the 1st flour was far extensive as compared with that of the water extract from the 3rd flour. Viscosity of the proteins from the 1st flour was higher than that of the proteins from the 3rd flour, e.g., the former APP showed around 10 times higher value than the latter APP. Viscosity of the proteins generally decreased by the addition of NaCl. Intrinsic viscosity of the APP was 10-40 times as high as that of soybean globulin. Taking the above results and the observation by scanning electron micrography into consideration, the relationship between the buckwheat proteins and the formation of buckwheat noodles was discussed.

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Antioxidative activities of 11 kinds of sugars and of 16 kinds of cane and beet sugars were studied. (1) Among eleven sugars examined, pentoses and hexoses showed prooxidative activities but disaccharides such as lactose and sucrose showed no influence on oxidative stability of linoleic acid. However, antioxidative activity was recognized with brown sugar. (2) Among sixteen cane and beet sugars examined, antioxidative activity was not detected with granulated sugar and soft yellow sugar showed prooxidative activity on oxidative stability of linoleic acid. However, five brown sugars showed strongly antioxidative activity. (3) It was confirmed that antioxidative activity of brown sugar and prooxidative activity of soft yellow sugar are influenced by trace elements (iron and copper), nitrogenous and colored substances contaimed in sugar. (4) In the comparison of antioxidative activities of raw sugars, granulated sugar and molasses, the highest activity was recognized with molasses.

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Lipid and fatty acid compositions of the total lipids and fatty acid compositions of the fractionated lipids in meat and viscera of horse mackerel, Trachurus juponicus in four seasons were examined by means of thin layer chromatography (TLC) and gas liquid chromatography (GLC). The total lipids were extracted with BLIGH and DYER method and fractionated by TLC. Fatty acid compositions of the total and fractionated lipids were determined by GLC.
The results obtained were as follows: (1) The total lipid content was higher in spring and summer than in autumn and winter, and it seems to be caused by the increase of triacylglycerines. On the other hand, the compound lipid content was constant through the year. (2) C 16:0 acid content (%) in the total lipids was constant through the year. C 18:1 acid content (%) was rather high in spring and summer, on the contrary, C 22:6 acid content (%) was rather high in winter and autumn. (3) C 22:6 acid Content (%) was higher in the compound lipid fraction than in the other fractions and it seems that this phenomenon relates to the increase of C 22:6 acid content in the total lipids in winter.

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This study was conducted in order to investigate factors concerning with hardness and discoloration of sweetpotato chips. (1) Hardness of sweetpotato chips was apparently influenced by oil content and blister formation that occured in tissue of chips during deep-fat frying. Enhanced blister formation in the chips resulted in an increase in oil content. These chips were found to exhibit softness and increased crispness. (2) The void space was scarcely observed in untreated sweetpotato chips. This physical characteristic was presumed to be the predominant cause of hardening of sweetpotato chips. (3) The lessened blistering in untreated sweetpotato chips may be due to the rapid escape of expanding water vapor from the sliced tissues during deep-fat frying. (4) Maltose content in raw material was found to be extremely low (less thah 0.1% wet basis). However its increment during deep-fat frying was apparently noticeable. The increase in maltose during deep-fat frying was considered to be one of the factors responsible for the discoloration of chips.

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A study was carried out on the amino acids constituting bitter peptides isolated and purified from Gouda-type cheese. Results are as follows: 1. Gouda-type cheese contains more than four kinds of bitter peptides with the molecular weight of 500 to 2, 000. 2. It is supposed that one of the four kinds of bitter peptides may be produced from either αs-or k-casein, and the others are produced from β-casein.

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A small amount of saccharin in milk beverages and fermented milk beverages was determined by gas chromatography. The results obtained were as follows: Saccharin was extracted by dialysis using cellulose tube and then methylated by diazomethane. The detecter of the gas chromatograph should be changed by the amount of saccharin which was analysed. FPD and ECD were suitable for the detection of μg of saccharin, and FID was suitable for mg of saccharin. The recovery rate was 80-100% in each case. It was revealed that this method was applicable to milk beverages and fermented milk beverages containing interfering substances.

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This work was undertaken to obtain technological information on the manufacturing process of hams by a multiple pickle injector. In this paper, the effect of polyphosphate added in loins injected with pickle on water holding capacity, color forming ratio, remaining rate of NO^-₂ and others was investigated. (1) Water holding capacity of cooked cured loin with 2% NaCl increased significantly with an increase of the amount of polyphosphate injected. An addition of polyphosphate in the amount of 0.3% or more maintained a relatively high constant level of water holding capacity of loin. (2) Cut surface of cooked cured loin having 0.5% of polyphosphate was considerably lowered in Hunter L and b-values in comparison with that having no polyphosphate. (3) The remaining rate of NO^-₂ in loin increased with an increase of the amount of polyphosphate, on the contrary, the color forming ratio was lowered. Particularly, the injection of 0.5% or more of polyphosphate induced a marked lowering of color forming ratio. (4) It was found that the distribution of polyphosphate in loin injected with pickle was uneven, indicating a partially high content of polyphosphate.

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