This study examines the effects of starch type on the properties of eisei-boro samples which had been prepared from potato starch raw material and three kinds of classified starch (large-grain, small-grain and very small-grain types). The overall evaluation by the rating method and ranking test gave the order of preference as raw material starch > large-grain starch > small-grain starch > very small-grain starch. The preference for raw material starch is considered to have been from the feeling of coolness and good mouth melting which resulted from the low gelatinization temperature and high gelatinization rate due to its 75% content of large-grain starch. The 25% content of small-grain starch and very small-grain starch in raw material starch resulted in a non-homogeneous structure that gave the easy breaking, aerial texture and good mouth feeling of eisei-boro.
The inhibitory effect of katsuo-dashi dried bonito stock on the taste of lactic acid was evaluated with a sensory test by trained panelists and with a taste sensor. The taste of the acid was inhibited by increasing katsuo-dashi concentration. Evaluation by a sensory test and gas chromatography-mass spectrometry(GC-MS) showed an inhibitory effect on the odor of acetic acid by adding katsuo-dashi. There was a correlation between the results of the inhibitory effect on the taste of the acid and the influence of the buffering action. The inhibition by katsuo-dashi of the acid odor was effectively demonstrated by GC-MS. These results indicate that katsuo-dashi was effective for suppressing the taste and odor of lactic acid, and are attributed to its buffering action.
We investigated the quality and antioxidative activity of “shio-zuke”, “miso-zuke” and “sunki-zuke” pickles prepared in the Laboratory of Cookery Science at Tokyo Kasei University and of various other pickles on the market. We measured the color difference, pH value, salt concentration, and rupture characteristics to investigate the quality of these pickles. Their antioxidative activity was measured by using the chemiluminescence, ORAC and HORAC methods. The weight, color difference and rupture strain of each pickle changed with the period of preservation. The respective pH values of “shio-zuke” and “miso-zuke” were from 4 to 6 and about pH5.2. There was high antioxidative activity in the salt solutions of “shio-zuke”, “miso-zuke” and “sunki-zuke”. “sunki-zuke” of the fermented pickles strongly scavenged the peroxyl and hydroxyl radicals. “suguki-zuke” and “takana-zuke” of the fermented commercial pickles also had high antioxidative activity.
The texture and structure of brown rice were compared to under-milled and well-milled rice to determine the most suitable method for cooking brown rice. The absorbance of brown rice at 20°C and 30°C was slower than that of milled rice, but reached a similar level after a 2-hour soaking at 60°C. The water content and grain size of brown rice were both smaller than milled rice when cooked. Cryo-scanning electron microscopy showed that the peel, seed coat and aleurone layer of brown rice were progressively removed as the degree of polishing increased. The amyloplasts in starch cells swelled more in milled rice than in brown rice when the rice was soaked in water.The small pores (water trace) in cooked rice increased with increasing degree of polishing, suggesting that the gelatinization of starch was sufficient. However, brown rice was rated worse than milled rice by a sensory evaluation.
We clarify how kouchuu choumi (seasoning in the mouth) influenced the taste of cooked rice when eating main and side dishes with rice. 74.8% of the subjects tested used kouchuu choumi (practicing group), and 25.2% did not (non-practicing group). There were no significant differences between the two groups concerning the frequency of rice intake or the and number and portion size of dishes at dinner, but the practicing group ate more rice. Although the preference for Japanese, Western, or Chinese cuisine was not related to the perceived tastiness when eating such dishes with rice, the selected responses of “dishes requiring rice to taste good” and “dishes with which rice tastes good” were positively correlated. Compared to the non-practicing group, a significantly larger number of people in the practicing group selected dishes using oils or butter and fatty dishes as those with which rice tasted good. The differences between the two groups were also significant for such fish dishes as sioyaki, nizakana, and sashimi eaten as the main course in Japanese cuisine, as well as for dishes considered to be often eaten with rice such as nikujaga and kinpira-gobo.
Dough and bread samples were prepared with various kinds of fermented liquid made from raisins, koji and yoghurt, and their physical properties, health functions and preferences were examined. The dough prepared with fermented koji liquid made by the sponge dough method showed more deterioration in its expansibility of the gluten by enzymes than the equivalent dough made by the straight dough method. Swelling of the bread was consequently poorer, and its rupture energy was higher. The specific volume of the bread samples prepared with fermented yogurt liquid by the sponge dough method was greater, and its rupture energy was lower. This suggested that the porous structure of the crumb influenced the physical properties. The antioxidative activity of these bread samples was higher than that of bread made with dry yeast. The bread samples prepared with fermented raisin and yogurt liquid were also much preferred by a sensory evaluation. It thus was found useful to add fermented liquid originating in food material to these bread samples.
The gelatinization properties of four kinds of noodles, Japanese (flour and salt water), kansui (flour and kansui), egg (flour and egg white) and egg and kansui (flour, egg white and kansui), were measured by the β-amylase-pullulanase (BAP) method and Fourier-transform infrared spectroscopy (FT-IR/ATR). The peak height at around 1,025 cm−1 of the FT-IR spectra markedly increased with increasing ratio of pre-gelatinized flour. The absorbance at this wavelength reflects an increase in the OH groups which were hydrated due to the gelatinization of starch. There was a high correlation in the degree of gelatinization between the FT-IR method and BAP method, although the value with FT-IR method was slightly higher. This result might have been due to the difference of the remaining protein between the two methods of measurement. There was a high correlation between the values for breaking stress and breaking energy after one day of storage by the FT-IR and BAP methods. This suggests the influence of moisture penetrating inside the noodles which equalized the hardness.
The flow characteristics and static viscoelasticity of quinoa starch at low paste concentrations were compared with those of rice and corn starch pastes. The flow characteristics of 2%, 3% and 4% pastes of the three different starches were measured at temperatures of 20, 30, 40 and 50°C. The dependence of concentration on the temperature of the quinoa starch paste was lower than that of the rice and corn starch pastes. The creep curves for each gel measured at 5°C were analyzed by a mechanical model of four elements comprising a Hookean model, Voigt model for retarded elastic modulus and viscosity, and Newtonian model. The paste of the quinoa starch showed the shortest retardation time and lowest Newtonian viscosity. In terms of the rupture properties, the gel of the quinoa starch showed the lowest values for the rupture stress, rupture energy and first modulus.
Sweet potato has been eaten by itself as a substitute for the staple food or mixed with rice in such dishes as imomeshi (cooked rice with sweet potato) and imogayu (rice gruel with sweet potato). We investigated the areas where these dishes have been eaten during the Taisho, Showa and Heisei eras, and related this consumption to the transfiguration and characteristics of each era and area. The results show that the area for eating imomeshi has been spreading from the western to eastern part of Japan during the passing of these eras, while eating imogayu has remained in western Japan. It seems that the spreading popularity of sweet potato was responsible for wider geographical area and familiarization of eating imomeshi. It also seems likely that the different image and eating habits of rice gruel between western and eastern Japan influenced the localization of eating imogayu to western Japan.