The relationship between overall acceptability and physicochemical properties was carried out on 31 types of rice employing sensory evaluation and objective analysis.
1. There was a high correlation between sweetness and overall acceptability in both analytical and preference tests (r=0.88 and r=0.92), but differences between samples were small.
2. For taste, a high correlation (r=0.95) between desirability of taste and overall acceptability was observed, but there was only a low correlation (r=0.23) between strength of taste and overall acceptability, and moreover, a low correlation (r=0.25) between preference and analytical tests.
3. A high multiple correlation coefficient (MR) of 0.97 for the overall acceptability using four attributes desirability of stickiness, desirability of sweetness, whiteness, and transparency was obtained by the multiple regression analysis.
4. Desirability of stickiness, transparency, and whiteness, which make a large contribution to overall acceptability were substituted by objective measurements. Desirability of stickiness was expressed in terms of amylose ratio, thousand grain weight of rice, and whole rice grain rate (MR=0.87), transparency was expressed in terms of the L value and the luster as 60° and 75° angles of incidence (MR=0.66), and whiteness was expressed in terms of whiteness level and the b value (MR=0.71).
5. Overall acceptability of cooked rice was expressed in terms of three attributes, amylose ratio, L value and luster (60°), with a multiple correlation coefficient of 0.76.

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Measurements were conducted for whole grain and outer layer components which are considered to contribute to taste of 31 types of rice. These results were added to the objective measurement method for eating quality of cooked rice according to the previous report, achieving even greater precision.
1. Examining the externality rate which expresses the externality rate of each component in the outer layers, water content was distributed evenly throughout the samples, but protein, Mg, K, total sugar, reducing sugars, free sugars, and free amino acids all have externality rates higher than 13%, making it clear that they predominate in the outer layers of the rice.
2. It was possible to express desirability of sweetness, which was seen to have a high correlation with the overall acceptability of cooked rice, in terms of three items, the total sugar in the whole grain, sucrose in the outer layers, and phenylalanine in the whole grain.
3. Overall acceptability of cooked rice could be expressed in terms of three items, sucrose in the outer layers, the L value, and the amylose ratio, with a multiple correlation coefficient of 0.85, substantially higher than multiple correlation coefficient of 0.68 from the objective measurement formula in the previous report 19) obtained from physical properties, and making it clear that better evaluation of the overall acceptability of cooked rice is possible.

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In order to establish the cooking condition of “Nashi-modoki” (mock-pear), rheological properties, sensory evaluation and microscopic observation of the potato cooked in boiling water or 30% vinegar solution were investigated under various conditions (e. g. cooking time and cut-size of potato).
The results are as follows:
1) When starch granules in potato were gelatinized in boiling water, crispness of potato was lost because of softening of the tissue.
2) By boiling the potato in 30% vinegar solution for 7-10 minutes, the crispness in sensory evaluation was found, and only little changes in cell walls were observed in microscopic examinations.
3) Effects of the cutting size and the boiling time on crispness of potatoes cooked in 30% vinegar solution were investigated. As a result, it was found that the crispness of “Nashi-modoki” was kept at the wider range of boiling time when the potato was cut in the thiner size.

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This study clarifies the cooking methods used for sesame seeds throughout the world. Answers to a questionnaire were received from 252 persons in 38 countries during January-March 1993, and literature research was conducted on “Sekai no tabemono” published by Asahi (1980-1982) and on “Africa and Arab cooking”.
In East Asia, both white and black seeds are used for cooking in the whole, rough ground or paste form. On the other hand, in the Near and Middle East, mainly the white seeds are used in the paste form. The difference in the usage of sesame between the two regions seems to principally depend upon the degree of grinding.
South Asian people often eat sesame seed, although its characteristic usages as a food was not clear from this examination. In North America, only the granular type of sesame seeds are used, while in Europe and South America, very little use of the seeds was found.
It is apparent from these investigations that the use of sesame depends on the dietary culture established in each area of the world.

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Qualities of sesame seeds differing in colors of the husks were examined at the points of pigments of husk, a roasting odor, palatability of roasted sesame and antioxidative activity of roasted sesame oil. The pigments of husk were extracted and examined by spectrophotometer and thin layer chromatography. The head space volatiles of roasted sesame seeds with white, black or gold husks were analyzed by gas chromatography and their aroma concentrates were analyzed by gas chromatography-mass spectrometry. Their palatabilities were evaluated by sensory tests using riceballs and crackers. The antioxidative activities of three roasted sesame seed oils were investigated by weighing method and the peroxide value. The results were as follows;
1) The husk of gold sesame had a yellow pigment which was not included in that of white or black sesame.
2) The roasted black sesame seeds which had a heavy odor were not preferable and the rosted gold sesame seeds which had a mild fragrant and sweet aroma were preferable.
3) The antioxidative activity of roasted black sesame seed oil was the strongest in three samples.
4) It seems to be preferable that roasted gold sesame seeds having antioxidative activity and nutty flavor are used in the sameway as other kinds of nuts.

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The suitable conditions of cooking for three kinds of branded rices, i. e., Hitomebore, Koshihikari, and Sasanishiki were investigated by controlling the amounts of water added. While Koshihikari and Sasanishiki are popular as rice with good palatability variety, the properties of Hitomebore have little been examined.
The results obtained were as followes:
The component contents of amylose, crude protein, potassium and magnesium in the above three kinds of rices showed the good effects on the taste of cooked rice. Moreover, the relationship between the properties of cooked rice and the increase of rice weight on cooking was revealed. When the weight of cooked Koshihikari was 2.16-2.36 times that of uncooked rice, the better tastes of cooked rice with moderate hardness and stickiness were given. For Sasanishiki the desirable tastes with moderate hardness were given by reducing the increase of rice weight on cooking. On the other hand, for Hitomebore the desirable tastes with moderate softness and stickiness were given by raising the increase rice weight on cooking.

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