A study was conducted to determine how frying slices of potato would enhance the antioxidative activity. The content per unit weight of such antioxidants as L-ascorbic acid and chlorogenic acid in raw potato was nearly doubled when the slices were fried. Ultrafiltration of the water-soluble extract taken from the potato chips revealed the medium moleculare weight fraction of 3,000 to 20,000 to have high anti-oxidative activity, although the amount was small. This medium moleculare weight fraction had a strong brown color, due to melanoidin. There was a large amount of the fraction with a molecular weight of less than 3,000, and this fraction contributed 91% of the total antioxidative activity. It appears that chlorogenic acid and melanoidin were responsible for the antioxidative activity of this low molecular weight fraction. The DPPH radical scavenging activity of 19 kinds of potato snack foods was compared. There was higher activity in the potato chips made from raw potato than in those that had been more highly processed.
The antioxidative activity of red and white Welsh onions was evaluated by measuring the radical scavenging and ferric reducing antioxidative activities (TEAC and FRAP, respectively). Both activities of red Welsh onion were much higher than those of the white variety, the strong antioxidative activities being found in the red, and not in the white or green part of red Welsh onion. After heating for 30 or 60 min in boiling water, TEAC in the vegetable tissue of red Welsh onion was decreased to 25-30% of the level in the raw sample; about 40% of the activity had been extracted into the boiling water, the sum of these activities being 60-70% of the level in the raw sample. In the case of FRAP, about 25% was found in the vegetable tissue and about 30% in the boiling water, the sum of these activities being 50-60% of that in the raw sample. The antioxidative components in the three parts of red Welsh onion were also estimated: high amounts of quercetin and anthocyanin were found in the red part, ascorbic acid was found in the white part, and quercetin, kaempferol, and ascorbic acid were found in the green part.
Egg noodles have characteristic eating quality. The physical properties of the dough and cooked noodles prepared with or without egg were examined by a Reometer, and the texture of the cooked noodles was evaluated by a sensory test. The dough kneaded with the egg was easy to produce and was required no resting time. The sensory test indicated that the egg noodles were harder, slightly more sticky and slightly more elastic than the Japanese noodles. The breaking stress value of the egg noodles measured by the Reometer was higher than that of the Japanese noodles. A microscopic observation revealed clearly recognizable endosperm cells at the center of both the egg noodles and Japanese noodles. These endosperm cells around the outside of the boiled Japanese noodles had swelled and crumbled, while the shape of the endosperm cells in the egg noodles had been retained in the amorphous complex of wheat proteins and egg.
Potato was used as the test material to compare the degree of deterioration incurred when boiling vacuumcooked dishes as opposed to those prepared by conventional cooking methods, and to assess the effect of different kinds of added seasoning. The increased rupture strength and reduced deterioration resulting from boiling was evident for the vacuum-cooked potatoes, as compared to those cooked by normal methods. With both the normal and vacuum-cooking methods, the more the amount of salt added to the broth, the higher the rupture value. The amount of pectin eluted into the broth peaked with the addition of sugar, a higher value being apparent with the normally-cooked food than with that prepared by vacuum cooking. A texture check revealed that the gaps between tissues were increased by the addition of sugar.
A questionnaire survey was conducted to evaluate the difference in liking for commercial bottled drinking water (CBDW) by different graders of a women's university. The third and fourth graders recognized the difference between water with a low mineral content and water with a high mineral content more easily than the first and second graders (P<0.01). There was no difference in the intake frequency of CBDW among the different grader. Exercise and taking a bath both resulted in a higher frequency of drinking CBDW (P<0.001). The result of a sensory evaluation show that domestic CBDW was more favored than imported CBDW and tap water (P<0.05). The third and fourth graders could distinguish the taste quality of domestic CBDW more easily than the first and second graders (P<0.05). Green tea extracted with domestic CBDW was more favored (P<0.05) than that extracted with other types of water, the third and fourth graders having greater ability than the first graders (P<0.05) to distinguish the green tea.
Salmon and yellowtail are recognized as special fishes in Niigata, Nagano, and Toyama prefectures. The traditional dish of Shiobiki Sake originated in the Murakami region of Niigata prefecture, and salmon became popular in the Iiyama, Nagano and Saku districts of Nagano prefecture from its fishing in the Chikuma river. On the other hand, yellowtail became popular in the Matsumoto, Suwa, Ina, and Iida districts of Nagano prefecture due to being on the supply route for salted yellowtail from Toyama prefecture. Toyama bay provides good fishing grounds for catching yellowtail in the winter as Kannburi, while Toyama prefecture is recognized for its development of the fishing method, processing technique and distribution of yellowtail.