A series of feeding experiments was performed to examine whether sesame lignan substances (sesaminol and sesamin) might exert a tocopherol (Toc) /tocotrienol (Toc-3) enhancement effect in rats. A mixture of Toc and Toc-3 (T-mix) was made up composed of α-Toc (23%), α-Toc-3 (22%), β-Toc-3 (5 %), γ-Toc-3 (34 %), δ-Toc-3 (10 %) and a small amount of β-and γ-Toc, and a diet containing 20 mg/kg (A) or 50 mg/kg (B) each this T-mix was given to the rats for 8 weeks. In the rats fed on diet A, (a) hemolysis of the red blood cells, (b) plasma pyruvate kinase, and (c) plasma and liver lipoperoxides were elevated in comparison to the case with diet B, whereas these values declined when 0.1 % sesaminol was supplemented to each diet. The major component of Toc in both the plasma and liver was found to be α-Toc, while a small amount of α-Toc-3 was detectable and γ-Toc-3 was undetectable. Supplementation of sesaminol caused a marked elevation of α-Toc; although the concentration of α-Toc-3 was also elevated, its content remained low. α-Toc was the predominant component in the rats fed on sesaminol. Sesamin exhibited an similar effect on the rats, but to a much lesser extent in comparison with the effect of sesaminol.

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Enterobacter cloacae GAO, a leavening bacterium, was studied for its assimilation of organic acids contained in a culture broth.E. cloacae GAO produced lactic acid and formic acid therefore, the lactate dehydrogenase (LDH) of E. cloacae GAO may affect the production of hydrogen gas by the bacterium. We investigated the purification and characteristics of the lactate dehydrogenase from E. cloacae GAO. The last purification step resulted in the specific activity of the enzyme being increased 48.5-fold with a yield of 4.6%. The molecular weight of the purified enzyme was approximately 115, 000 by gel filtration, being composed of four subunits each with a molecular weight 31, 000 as evaluated by SDS-polyacrylamide gel electrophoresis. The optimum pH and temperature for the enzyme activity were 7.5 and 30°C, respectively. The lactate dehydrogenase was stable at 40°C and between pH 7 and 9, and the enzyme activity was strongly inhibited by Cu²⁺ and Mn²⁺. The enzyme predominantly contained glutamic acid in its amino acid composition.

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The characteristic anthocyanin, vitamin C, dietary fiber and sucrose contents of new types of colored potatoes were studied.
The total dietary fiber level in the violet, red and yellow potatoes were 0.75, 0.66 and 0.85%, respectively. The total vitamin C contents of the violet, red and yellow potatoes were 25.3, 14.1 and 31.5 mg/100 g, respectively, while the anthocyanin contents of the violet, red and yellow potatoes were 142, 148 and 17 mg/100 g, respectively.
The main anthocyanin structures in the violet and red potatoes were determined to be petanin and pelanin by FAB-MS and1 H-NMR analysis.
The red potato anthocyanin was very stable to heat and UV irradiation.
Sucrose in the red and yellow potatoes increased during low-temperature storage.

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The effect of absorped moisture on the textural properties of low-moisture foods was investigated. Thirty-one kinds of confectionery and dry goods on the market were left standing at six levels ofrelative humidity controlled by a saturated salt solution.
The breaking force and initial elastic modulus of the moisture-equilibrated samples were measured, and the test samples were classified into two groups. One group (I) comprised those samples which gradually became softer in texture, and the other group (II) which retained a similar texture to the original one or became harder than the original one. It was found that the samples in both groupsbegan to change their texture at around 68%RH.
The water sorption isotherm of each test sample was measured at the six levels of relative humidity. Both groups of samples exhibited on S-shaped line with two inflexion points. The monolayer water content of all samples was calculated by the BET method to be 2.5-14/100 g of dry matter.
Most samples, however, either remaind unsoftened or were temporarily hardened in the limited range from monolayer to multilayer.
The softening phenomenon started above approx. 5% water content with group I, but above approx. 10% water content had no effect with group II. In comparison with the group II samples, those in group I had less monolayer water content and much free water under high-moisture conditions.

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Peptides in beef which had been heated at 60°C for 6 h were fractionated into four groups according to their molecular weight (MW) : I, less than 500; II, 500-1, 000; III, 1, 000-10, 000; and IV, 10, 000 and more.The combination of fractions I and II increased the “umami” sensation. While the presence of II, III and IV with fraction I did not increase this sensation. Umami was increased when fraction II was added to onion soup which has few peptides. The major fractions with molecular weights of 500-1, 000 and 1, 000-10, 000 were both basic.

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Nangmyeon is one of the most popular noodles in Korea and has a characteristic texture. A sensory analysis was carried out to define the characteristic texture of nangmyeon in comparison with other popular noodles. Seven different recipes for the ingredients and/or their ratio of nangmyeon were selected from cookery books for the experiment, involving three kinds of Pyongyang nangmyeon, three kinds of Hamgheung nangmyeon and a modern commercial type. These recipes were used to define the mixing time, amount of water to be added and the boiling time before serving the noodles. Fifteen kinds of other popular noodles were selected to compare their textural properties with those of nangmyeon. First, the words used to describe the texture of noodles were collected. Based on the selected 5 words, a sensory analysis was performed, and a principal component analysis was conducted. The 22 types of noodles were then divided into 5 groups according to the first and second components. The texture of the two types of traditional Korean nangmyeon fell into different groups. Hamgheung nangmyeon and the commercial Korean nangmyeon made up one group and could be differentiated.

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A survey of the effect childhood diet on the taste sensitivity and personality in later life was conducted on college students from 18 to 20 years of age (93 females). The sensitivity toward sweet, sour, salty, bitter and umami tastes was measured by using aqueous solutions.
The students recalled the tastes and nutritional balance from childhood when preparing daily meals. Dishes such as Hamburg steak, curry and rice, and nimono were eaten, together with snacks, cakes and sweet rolls by most of the 93 subjects during childhood.
Most of the subjects recalled eating tasty and enjoyable meals around the family dinner table, and that their mothers prepared everything from scratch. A few of the students recalled eating meals alone and having a lot of fast food.
Taste sensitivity tests with aqueous solutions showed that the subjects could perceive 0.1-0. 6% of sucrose, 0.01-0.05% of citric acid, 0.01-0.06% of sodium chloride, 1.0 × 10^-9-1.0 × 10^-4% of quinine, and 0.005-0.035% of MSG. Little difference was found between the diet in childhood and the subsequent taste sensitivity.
There was, however, a significant correlation between the diet in childhood and 8 of the 12 personality traits. A balanced diet in childhood had a good effect on personality (i.e., absence of depression, an active demeanor and social extravesion).
We conclude that a good diet during childhood had little influence on taste sensitivity in later life, while it had a positive influence on personality development.

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A comparative study of preference for nangmyeon noodles between 107 Japanese and 110 Korean students was carried out on 4 kinds of nangmyeon. Two traditional Korean nangmyeon noodles, the Pyongyang type and Hamheung type, and a modern commercial type of nangmyeon were made in the laboratory with a special machine supplied from Korea. The Japanese nangmyeon noodles were purchased from a retail Japanese market. The Japanese students didn't show any particular preference because they were not familiar with nangmyeon, while the Korean students preferred the Hamheung type most. The texture which the Korean students preferred was strongly elastic and not easy to bite. These textural properties were not apparent in Japanese noodles and are characteristic of Korean nangmyeon noodles.

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Most plant foods such as vegetables, fruit, seaweed and mushrooms contain antimutagenic or anticarcinogenic compounds. These compounds may be altered or lost during processing and cooking. Therefore, it is very important to investigate the change in antimutagenicity of a food due to processing and cooking. The objective of the first stage of this study was to examine the antimutagenicity of water-soluble and fat-soluble substances in plant foods. Food samples were selected from popular seasonal vegetables that are commonly available. The water-soluble fraction and fat-soluble fraction were extracted from each freeze-dried plant food with a 0.1 M phosphate buffer and methyl alcohol, respectively. The antimutagenic activity was evaluated by the Ames method to examine the mutagenicity of Trp-P-1, Trp-P-2 and 2-hydroxy- (1-N-nitrosoindolyl) propionic acid (NIHP) toward Salmonella typhimurium TA 98.
Twenty percent of the forty plant juices tested reduced the mutagenicity of Trp-P-1 by more than 50 %, and 35% of the extracts from the other 29 vegetables reduced mutagenicity of NIHP by more than 50 %. Eighty three percent of the water-soluble fractions extracted from 24 freeze-dried plant foods showed antimutagenic activity toward Trp-P-2. On the other hand, only 25% of the fat-soluble fractions from the freeze-dried plant foods showed antimutagenicity, although a few of them demonstrated very strong activity. Seventeen percent of the tested plant foods had antimutagenicity in both the water-soluble and fat-soluble fractions. Most of the plant foods tested contained antimutagens in their water-soluble fractions.

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