Recently, the utilization of silk protein (sericin and fibroin) is the food field is becoming practicable. As a food material, approximately 6-7t (the 2000 year) of fibroin was used and the market is expanding in Japan. However, the function of silk protein as a food material is poorly understood except for the investigation of its anti-oxidative activity. Therefore, we examined the nutritional function of water-soluble sericin such as its extensive purification conditions, proximate composition, and digestibility.The amino acid composition of purified water-soluble sericin was the same as the yarn silk protein. Moreover, the digestibility of water-soluble sericin was 38% when treated with pepsintrypsin-chymotrypsin in vitro.On the other hand, its in vivo digestibility was approximately 45%.From the result that sericin can be digested and absorbed, we speculatedthat when sericin is used as a food material, it may contain a nutritional function which may contribute to human health.
To investigate the influence of food information on the menu planning in schol lunch management practice, the problems regarding the daily lunches of women college students and the education method of eating, we have carried out an investigation involving 150 women students by dividing them into two groups (group A: eating a box lunch over 4 times a week, 84 students, 56%; group B: eating-out over 4 times a week, 66 students, 44%). 1) The market re-purchase price of food materials (three individual stores) was about 6% lower and the hitting ratio in visually predicting the weights of 10 kinds of foods was 2-28% higher than the first time purchase, indicating the effective mastering of the points in purchasing materials. 2) Food materials have been purchased from supermarkets in a frequency as high as 48%. The selection of food materials was 34% based on the expiration date or use-bydate, 31% on a sensory evaluation but only 15% on the JAS indications. 3) Only 45% and 30% of the students, respectively, have shown interest in the consumption trend and production/distribution of foods. This shows a need for consumer education. 4) Concerning the student subjects, their Body Mass Index (BMI) was 20.1±1.7, average somatic fat rate was 23.9±2.3%, and 37.3% of the students with a standard figure have a tendency of hidden obesity. 5) The daily energy intake was 74.6% of the daily energy expenditure, being significantly low (p<0.05). 6) A trend in taking lunch for both group A and B was economy and simplicity. 7) 35.7% of the students in group A and 45.4% in group B did not take their lunch more than once a week. 8) In their daily lunch, only three-eighths of the dietary allowance was satisfied and the intakes were all insufficient for energy, Ca, Fe, vitamins and dietary fiber but excessive for lipids. The combinations of staple foods and drink only were in ranked high suggesting a lack of consciousness about lunch. Nevertheless, the nutrient intake was improved in the school lunch menu. 9) The lunch fee averaged 350 yen and was almost the same as the school lunch. A high percentage of the students was satisfied with the lunch fee and the school lunch. 10) A relation was observed between the school lunch leftovers and the amount or taste of the menu (p<0.01).
The determination of the nitrogen content in 58 foodstuff samples from 8 food groups, which included cereals, potatoes, pulses, vegetables, fruits, fishes and meats, by the combustion method (CN) and the Kjeldahl method (KN) was investigated. Although the nitrogen content by the CN had slightly high levels as compared to the nitrogen content from the KN, it was found that the CN highly correlated with the KN. We also investigated the crude protein content (CN and KN) in 20 packed meals and found that the CN correlated with the KN. The obtained results showed that the CN was viable and an ideal alternative to the KN for the determination of the crude protein content in foods.
In the past, when boiling spinach, it is suggested that one should use boiling water. It is said that this removes the oxalic acid ingredient and other ingredients with a non-taste, and improves the color. In this study the temperature of the boiling water and the influence of the boiling time were evaluated. 1) The oxalic acid content decreased when the temperature of the boiling water was high and when the boiling time was long. 2) There was no difference in the color of the boiled spinach. 3) Even if the boiling time was long at 60 and 70°C, the oxalic acid content and the change in its strength were low and the heating was insufficient. 4) At 80°C with a sufficient boiling time, a moderate condition was attained. For the oxalic acid content and softness evaluation, heating was from 2 to 3 minutes at 100°C which was considered moderate in the past. 5) At 100°C, the range in the boiling time which can make spinach have a moderate condition was short. From 80 to 90°C, the time period was long. When boiling spinach is always kept in the hot water, boiling is not necessary and it is possible to say that the heating power should be maintained to provide an 80°C temperature or higher.
Generally, when boiling spinach, salt is added to the boiling water. When boiling with about 1% salt water, it is difficult for the composition to change and it is reported that the chlorophyll is also stable. Also, there is a report that there is no difference in the color even if salt is added and boiled. In thisstudy, we examined the influence that the salt content in the boiling hot water exerts on the spinach. Salt at 0.0, 0.25, 1.0, 2.0 and 4.0% was added to the boiling water and then its effect evaluated. 1) The higher the salt concentration, the stronger the salty taste, the sweetness was difficult for the oxalic acid to decrease and it affected the taste. 2) The higher the salt concentration, the softer the spinach. When the concentration was as high as 2.0%, it was too soft and the evaluation was low. 3) There was no difference in the color of the boiled spinach for 0-2.0% added salt. 4) For the salt concentration in the boiling water of 0.25-0.5% for the evaluation of the taste, the texture was good. Because there was no change in the good special color at 2.0% salt and it was difficult for the oxalic acid to decrease, it tasted bad and it was too soft. When adding no salt to the boiling water, there was no influence on the color, but thes weetness was weak and it was not solid.
The physicochemical properties and palatability of4rice samples milled at 95-96%(A), 93-94%(B), and 90-92%(C) milling rates and the germ rice for rice cultivar Hinohikari grown in and northern Kyushu were investigated. The milled rice samples A and B was larger than C in width, length, weight and the expansion coefficient after soaking in water. The water contents of the germ and the outer layer of the rice samples were higher than that of the inner layer. The water absorption rate of the germ rice was the highest among the 4 rice samples. The higher the milling rate of the rice sample, the harder the cooked rice at 24 hrs. after cooking as compared with the rice immediately after cooking. The results of the protein and amylose analyses for the 4 rice samples showed that the protein contents were higher in the outer layer, where as the amylose contents werehigher in the inner layer of the rice grain. The sensory test for the 4 cooked rice samples showed that cooked rice sample A was not better for palatability than the other cooked rice samples, whereas rice sample A and the germ rice, prepared as a soy sauce-seasoned rice, were shown to be better than that when not preparing with soy sauce-season.
The purpose of this study is to establish what kind of goat meat preparations are eaten in Korea (Republic Korea) and the southern parts of Japan (Okinawa and Amami). In Japan, goat dishes have been eaten only in these districts, but in Korea the dishes have been eaten all over the country. In Korea and Japan they are eaten by people in their thirties and forties. In Korea, however more women and young persons have eaten them than in Japan. The frequency with which they are eaten is much the same in both countries. The reason they eat goat dishes is that the dishes are healthy and delicious. It is concluded that in Japan they prefer goat soup, whereas in Korea they prefer baked goat meat.