The effect on the inhibition of lipid oxidation was examined for cooking lard when iron, ascorbic acid and miso individually or in combination were boiled with ginger in water.
The oxidization was accelerated even with the very small amount of iron that was transferred from an iron pan to the boiling water.
However, this oxidization by iron was inhibited when ginger and ascorbic acid were used in combination, although the antioxidative effect was less than that without iron present.
When ginger was used together with miso, the antioxidative effect was less than with ginger alone; However, the oxidizing effect of iron was inhibited by the absorption of iron to the coloids present in miso.

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The kinetics for enzymatic browning of pulp samples from six apple cultivars (Fuji, Mutsu, Orin, Tsugaru, Jonagold, and Kogyoku) were examined. Reflectance was used to measure the extent of enzymatic browning and was evaluated by the Hunter color scale. The time-course plot of the color difference(ΔE)was related to the extent of browning and could be expressed by the equation, ΔE=B (1-exp (-kt)), where B and k are fitting parameters and t is the time in min. The B and k values were calculated by the non-linear least-squares method and respectively applied to the extent of browning and the browning rate constant. The rate and extent of browning were high with the Fuji, Mutsu, and Orin pulp samples, and low with Tsugaru and Jonagold. Although Kogyoku showed a low browning rate, the extent of browning was high. The rate of browning was influenced by the ascorbic acid content and polyphenol oxidase (PPO) activity in the pulp. The extent of browning and PPO activity showed good correlation. However, there was no correlation between the chlorogenic acid content and the extent of browning with the six apple cultivars.

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The suitability for processing of glutinous rice samples imported from Thailand, U. S. A. and China was evaluated against Mochihikari as the control, This being the main variety of glutinous rice produced in Nagano Prefecture.
The following five p arameters reported in the previous paper were used to evaluate the suitability for processing: the hardness of mochi dough, colour tone (L⋅a⋅b), protein content, gelatinization temperature, and the temperature for maximum viscosity two additional parameters related to the paste property, i. e., the total free sugar content and the total free amino acid content were also measured. A score was calculated by summing these seven values and visualized on a radar chart. The glutinous rice from U. S. A. showed the most similar properties to those of Mochihikari, with the rice from China next. The glutinous rice from Thailand had very different properties.

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Sponge cake batter samples individually incorporating xylitol, sucrose or one of four kinds of sugar alcohol, or combinations of these were prepared by whole-egg whipping or by all-in mixing with an emulsifier, and then baked at 170°C for 30 minutes.
The batter specific gravity and the transition peak temperature (Tp) by DSC, and the cake temperature during baking, the shrinkage time and the relative volume were measured.
Some batter samples including those with more than 50% xylitol as the sugar ingredient, showed a lower specific gravity than the others. The batter Tp was correlated with the rate of increase and the maximum cake temperature, and the period for the formation of a sponge structure (difference between the initiation time of cake shrinkage and corresponding time of the batter Tp) versus Tp plots showed a negative linear correlation. These phenomena were similar with both sample groups, each group having had the batter prepared by one of the two different methods, indicating that the different preparation methods had little effect on the baking process.
There was a correlation, which could be approximated by a quadratic equation having a maximum temperature of about 90°C, between batter Tp and there lative volume of the cake. This equation suggested that the addition of some sugars to xylitol that increased the batter Tp value improved the cake volume, the sponge cake sample with only xylitol showing a small relative volume because the batter had a relatively low Tp value.

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The effects of cabbage juice on the mutagenicity of heterocyclic amines (Trp-P-1, Trp-P-2 and IQ)were investigated. The mutagenicity was measured by the Ames method, using S. typhimurium TA 98in the presence of S-9 mix. Cabbage juice was separated into a high-molecular-weight fraction (F-I)and two low-molecular-weight fractions (F-II and F-III) by gel filtration with Sephadex G-25. The FI fraction had higher desmutagenicity than the F-II fraction toward Trp-P-1, Trp-P-2 and IQ. However, the F-III fraction had no desmutagenicity toward these heterocyclic amines. In the present study, high peroxidase activity was detected in the F-I fraction. Since commercial horseradish peroxidase shows high desmutagenicity toward heterocyclic amines, the desmutagenic factor in the F-I fraction is presumed to have been peroxidase. Glucose, fructose and sucrose were observed in FII fraction. These saccharides showed moderate desmutagenicity toward Trp-P-1 and Trp-P-2, but showed low desmutagenicity toward IQ.

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We examined the effects of ingredients and boiling time on the quality of Nikogori.
The boiling time for making the firmest gel with yellowtail and Pacific cod was shorter than that with chicken wings. The firmest Nikogori was that formed from chicken wings, being firmer than that from yellowtail, while the gelling of broth from Pacific cod was very poor.
Gel made from chicken wings was relatively stable during long-term boiling. However, those from yellowtail and Pacific cod gradually became soft by boiling for more than 30 minutes.
The transparency of the broth decreased with increasing boiling time, and the amount of protein in the broth increased with yellowtail and chicken wings.
Proteins in the broth contained the gelatinous molecules forming Nikogori, as well as unidentified proteins hindering the gelation process.
The gelatinous molecules in the broth were changed to those of low molecular weight by long-term boiling so that the Nikogori became soft.

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We investigated the effect of mirin on Fried pork. Raw pork was marinated in water, mirin, nikiri-mirin or an ethanol solution for 17 hour. The quantity of soluble pork substances in the mirin marinade was lower than in the other solutions. The pork observed by electron microscopy. It was found that the structure of pork marinated in the mirin solution was hardly changed by frying. It is considered that the tissue of pork while beeing fried was maintained by the effect of ethanol and glucose contained in mirin.

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A highly viscous exudate was prepared by stirring “Mekabu” (sporophyll of Undone pinnatifida)after soaking in hot water. The viscosity of exudates prepared under different conditions (temperature and NaCl addition) was measured with an E type viscometer. To define the factor of change in its viscosity, the content and viscosity of dry matter in the viscous exudate were measured.
The influence of temperature and NaCl addition on the viscosity of sodium alginate extracted from “Mekabu” was investigated. The viscosity of the viscous exudate prepared at 20°C was 4.74cP, and it increased to 21.76 cP at 8°C. The viscosity of the viscous exudate was correlated with the content and viscosity of dry matter. The amount of the component which can maintain a high degree of viscosity at high temperature increased when the temperature of the preparation was raised.
NaCl addition decreased the viscosity of the viscous exudate during soaking and stirring, although it had had little influence on the content and viscosity of dry matter after dialysis. The viscosity of sodium alginate declined with NaCl addition. The decreased viscosity of the exudate was mainly responsible for the change in structure of dissolved polyelectrolytes from NaCl addition.

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Yellow yolk spheres vary in size by their site in the yolk and the difference of the hen egg (Mineki and Kobayashi,1997; Mineki,1999). Whether the sizes of yolk spheres are influenced by the weight of eggs and how many yolk spheres are packed within the yolk were examined.
Commercial eggs were weighed and steamed. The transverse sectional area, maximum width and maximum long dimension of yolk spheres in the inner, middle and outer layers of yolks were measured by image processing techniques.
The transverse sectional areas of the spheres ranged from 3.20×10³ to 9.88×10³μ m². The maximum width ranged from 60 to 99μ m. The maximum long dimension ranged from 71 to 124 pm. They were smaller in the outer layer and larger in the inner layer than in the middle layer.
The sizes of yolk spheres were directly correlated to the weight of the whole eggs and yolks. Smaller yolks contained smaller yolk spheres, and larger yolks contained larger yolk spheres.
The number of yolk spheres within a yolk was calculated from the transverse sectional areas of the yolk and yolk spheres.
The number of yolk spheres within a yolk was estimated to be about 1.8×10⁷, regardless of the egg weight.

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Almost all leafy vegetables are stored in a household refrigerator, but whether the storage attitude of the vegetables, for example, upright, laid down, or upside down, affects the quality or not remains unclear. Three kinds of vegetables, i. e., spinach (Spinacia oleracea L. ), “komatsuna” (Brassica chinesis L. var. komatsuna MATSUM) and “kaiware” (Raphanus sativas L. var. longipinnatus L. H. Bailey cv. Tokinashi) purchased from a retail market were stored at 4°C and 95% RH for 14 days. The vegetables were placed in the attitude of upright, laid down or upside down, and the quality was determined after 0,4,7 and 14 days of storage.
The weights of both spinach and “komatsuna” decreased by 5% and 10% after 7 and 14 days of storage, respectively. “Kaiware” had a wet spongy sheet in the roots, so we determined the moisture content instead of the fresh weight. There was no significant difference in the weight or moisture content among the three storage attitudes.
The amount of total vitamin C in the spinach decreased by 20-25%, 30% and 35% after 4,7 and 14days of storage, respectively. However no difference was apparent among the three storage attitudes. This change in vitamin C content was similar in “komatsuna” and “kaiware”, and some leaves of “komatsuna” turned yellow during storage.
A sensory analysis of boiled spinach and “komatsuna” indicated no significant differences in the green color, odor, taste, flavor, texture or overall preference among the three storage attitudes.
There was also no significant difference in the green color and odor of raw “kaiware” among the attitude. These findings indicate that the storage attitude does not significantly affect the retention of vitamin C nor the taste while storing spinach,“ komatsuna” and “kaiware” in a refrigerator.

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