Applications of superheated steam for food processing have been studied in recent years with several advantages. A new oven system, which generates superheated steam with micro droplets of hot water (Aqua-gas), was achieved spraying heated water into a heating chamber filled with the superheated steam. It was expected that the micro-droplets increased the heat transfer coefficient of the heating medium. It was also expected that water content of foods processed with this oven could be controlled by regulating the amount of the micro droplets in the superheated steam. Heat transfer rates of the Aqua-gas and the superheated steam maintained at 115°C were measured based on surface temperature of a heat flowmeter. The heat transfer rate of the Aqua-gas was larger than that of the superheated steam in the case the temperature of the heat transfer boundary was low. In addition the drying rate of the food sample was lower in the case of the Aqua-gas due to the effect of the micro droplets. An application of this new Aqua-gas system for surface pasteurization of flesh vegetables and the blanching were examined. Cucumber and carrot samples were pasteurized effectively with slight changes of its color and rheological properties in 30 seconds to 1 minute using this new Aqua-gas system. Potato salad, pasteurized by this new system, had better flavor and longer shelf life than potato salad prepared by the traditional method. The potatoes and broccoli were blanched by the Aqua-gas. The changes in the color, the rheological properties were smaller than the blanched sample by the hot water. The weight loss of the potato was small in the Aqua-gas. In addition, Bacillus subtilis spores on potato were pasteurized effectively by the Aqua-gas. These results suggest that safe fresh food and products with high quality and long shelf life can be provided using this new oven system.
The thermal conduction induced near to the heating plane was detected along the one-dimensional axis (x-axis) in foodstuffs such as a series of food models, cereal flour doughs, highly moisturized foods, etc during pan broiling (heating in a metal vessel) at 105°C, frying at 180°C, boiling at 100°C, steaming at 100°C, and baking at 170°C, using the newly provided heatineg devices. The velocity of increasing temperature monitored in each sample was ranked from the highest to the lowest in the order of frying, boiling, steaming, pan broiling and baking, irrespective of temperature in each heat transfer medium. The increasing temperature against heating time curves for all the samples were in conformity to an exponential equation derived from an assumption that a retardation phenomenon plays a role in the thermal conduction. This article describes the details about distinctive feature of the retardation phenomenon during heating procedures of foods.
The survival of mixed oral bacterial flora in bottled soft drinks by direct drinking during aerobic incubation has been previously reported. Various microaerophilic bacteria are also present in our mouth. The survival of mixed oral bacterial flora in bottled soft drinks by direct drinking during micro aerobic incubation is discussed. The viable cell counts during the microaerobic incubation were greater than those during aerobic incubation when bottled soft drinks were stored at 25°C for 8 hours after direct drinking. Gram negative Diplococcus (Genus Neisseria) were detected after 8 hours. The Genus Bacillus survived during the microaerobic incubation because the spore Genus Bacillus resised the unsuitable condition. The surviving bacterial flora in the bottled soft drinks did not differ between individuals during aerobic incubation.
Various kinds of oral bacterial flora become mixed in bottled soft drinks by direct drinking, but these bacteria decreased with time. It was suggested that Staphylococcus aureus (S.aureus) and Streptococcus pyogenes (S.pyogenes) were able to survive in some bottled soft drinks in our study. The survival of S.aureus and S.pyogenes that are often detected in oral becterial flora inoculated in bottled soft drinks, were discussed. In sports drinks and fermented milk-containing beverages, the number of S.aureus did not change, but S.pyogenes were dead within 5 hours. In barley tea drink, the number of S.aureus increased, but the number of S.pyogenes slightly decreased. In black tea with a milk drink, these 2 species increased. The pH of barley tea and black tea with a milk drink were about 6. The pH of the sports drink and fermented milk-containing beverage were about 3. It was suggested that the growth of these bacteria were affected by the pH rather than some of the ingredients in the soft drinks. In addition, at neutral pH, the black tea with a milk drink was suitabled for the growth of bacteria because it contained sugar and milk. Under the conditions of this study, the enterotoxin of S.aureus was not produced.
The preferred characteristics of Korean and Japanese kimchi are compared. The material combination was changed to 5 set as 0.75, 1.0, 1.2, 1.4, 1.6 for the powdered hot pepper and 5 set as 0, 0.5, 1.0, 1.5, 2.0 for the garlic and anchovies respectively. The sample was prepared by salting for 2, 4, 6, and 10 days, then the difference in taste preference between the Korea and Japan samples was compared by a sensory evaluation method using a 7 step estimation. The results of the analysis are as follows : 1. For Kimchi, the crispness decreased and sourness increased based on the salting term. In both country, the salting term of 6 and 10 days at pH 4 received high scores, while the term of 2 and 4 days received relatively low scores. 2. The evaluated items of Kimchi the such as strength and mildness of the garlic, hotness of the powdered hot pepper and Umami of the anchovies have a greater influence on the total evaluation than the crisp taste. 3. The Koreans have an accurate preference for the taste of Kimchi, while the Japanese do not have it. The evaluation showed a tendency of centralization. 4. The material combination of the highest preference was 1:1:1 for the powdered hot pepper, garlic and anchovies in order and a 6-day salting. The lowest one was 1:2:1 and a 2-day salting. 5. The Japanese showed a higher preference for Kimchi with a somewhat mild taste for the powdered hot pepper and garlic compared to the Koreans.
A survey of the actual lunchboxes of preschool children was conducted among the parents of kindergarteners to consider their problems and issues. The obtained results are as follows.: 1. Approximately one-third of the preschool childrens' lunchboxes could be referred to as “pretty much homemade”. 2. In preparing the lunchboxes, many of the parents gave special consideration to their children's favorite foods, color arrangement, easy edibilty, nutritional balance, etc, but few thought about food safety. 3. 62.5 percent of the parents appropriately replied that the lunchbox contents account for approximately one-third of the total energy for one day. 4. Rice was mostly used as the staple food in the lunchboxes, though only a few used plain white rice while many others used flavored boiled rice or rice balls. 5. An average of 5.6 side dishes were included in the lunchboxes. 6. An overlap in dishes prepared using oil was seen, together with the frequent use of meat, whereas the use of fish and vegetables was rather low, which was an issue. 7. Furthermore, expanding the child raising assistance project by incorporating food supporting programs is desired.
Teaching a good cooking practice using beans was carried out for fourth and fifth graders in an elementary school. Before and after the teaching, questionnaire surveys were conducted among the teaching group (150 children) and the control group (249 children). The educational effects and the relationship between the intake frequencies of beans, etc., and the children's healthy situations were investigated using these surveys. The results were as follows. 1) In the teaching group, after the teaching, the children's taste for beans and their will to eat beans were significantly improved and the intake frequency of beans at home showed a tendency to increase compared to the control group. 2) It was suggested that if the children felt that the beans were delicious by cooking and their taste for beans was improved, their beans intake would also increase. 3) For the investigated intake frequencies of four items at home, significant positive correlation was found between “beans” and “bean products” and between “cup noodle” and “convenience store rice ball”. Regarding healthy situations,“beans and bean products” showed a significant positive correlation and “convenience store food” showed a significant negative correlation. 4) In the teaching group, the intake frequency of convenience store food significantly decreased and the children's healthy situations significantly improved. 5) The“beans and bean products predominance group”regarding the intake frequency showed a significantly good health situation compared to the“convenience store food predominance group”. 6) It was suggested that the effect of having a good influence on children's healthy situations was expected by teaching children about traditional foods and how to eat them.
The good points of the nutritive balance based on the Japanese style eating habits are being evaluated worldwide. Dehydrated food is being investigateed as a health conscious type of food. In this study, we investigated dehydrated foods such as of vegetables, mushroom and fruit using the patent gazettes examined how to utilize them with respect to their value and the effect from the drying techniques as to the number of patents concerning the characteristics of the dehydrated foods and the nutrition. The patents suggest many way to make a powder, and use as an extempore food, chips, health food, diet food, confectionery material, and so on. As for the drying technique, there are many freezing and vacuums method for vegetables, and many high temperature heat treatments being used for drying mushrooms and fruits.
Six kinds of heated mushrooms after being damaged by slow freezing were analyzed for their 5'-GMP and RNA contents. 5'-GMP is a major umami component in mushrooms and is a degraded product from RNA. In some of the mushrooms,the RNA contents in the frozen mushrooms indicated significantly lower contents than those in raw mushrooms, while the others showed a tendency to decrease. Along with this tendency, the 5'-GMP contents in the frozen mushrooms significantly increased when compared with the contents in the raw mushrooms. Based on the electron microscope observations of the mushrooms tissues, it is thought that when slowly frozen mushrooms were heated, a lot of dripping occurred and the enzyme (RNase) action became active. A sensory evaluation was carried out for the Japanese pilafs which is rice cooked with frozen mushrooms or raw mushrooms. In pilafs using L.edodes, there was a significant difference in its taste. The pilaf using frozen mushrooms was more preferable than that using the raw mushrooms. In H.marmoreus, the taste, flavor, texture and total evaluation were significantly difference. The pilaf using frozen mushrooms got high evaluations. For T.matsutake, there was a significant difference only in the flavor. Concerning G.frondosa, a sensory evaluation was carried out using two kinds of Japanese pilafs. One was treated with salt and the other using soy souse. In the G.frondosa rice treated with salt, there were significantly differences in the color, texture and total evaluation. The pilaf using raw mushrooms was more preferable. On the other hand, for that treated with soy souse, there was no defference in the flavor. When these mushrooms were used as an ingredient of miso soup, the frozen mushrooms were more preferable than the raw mushrooms regarding the color, the taste, the taste of the mushrooms and the total evaluation. Based on these results, we concluded that it is useful and advantageous when cooking to use mushrooms after freezing without blanching, because their sturdy tissues when defrosting and the increase in the umami taste by heating.
The inhibitory effect on the increasing the postprandial blood glucose levels by Banaba extract capsule enriched corosolic acid was evaluated. First of all, blood glucose levels of 12 subjects including of 7 males and 5 females were measured at the time of fasting and in 30, 60, and 120 minutes after being ingested only starch meal (540 kcal). Then a soft capsule of Banaba extract contained high 10mg quantity of corosolic acid was orally administered to all subjects at every morning for two weeks. The inhibitory effect by the capsule was evaluated to compare with the postprandial blood glucose levels by being ingested the only starch meal. As a result, a significant inhibitory effect was observed at the each point of fasting and 30, 60 and 120 minutes within only one week after administrating the soft capsule. Both the weight loss and the improvement of BMI were observed also after two weeks administrating. It is clear that the soft capsule of Banaba extract contained high 10mg quantity of corosolic acid is available, as no adverse effect was observed during and after the trial.
From October through December 2003, a survey regarding beverages was carried out on 306 female university students from Ulaanbaatar and 283 of them from provincial areas. The following results became clear. 1. In both (urbanites and provincials) cases, hot water was the most popular beverages among the female university students. However, the former urbanites frequently consumed black tea or coffee while the latter provincials showed a high frequency in suutei chai and khar chai. 2. Coffee was frequently taken between meals, but black tea was regarded as a beverage to be taken together with a meal. 3. Compared to the Ulaanbaatar urbanites, the provincials preferred suutei chai far more than black tea. Thus, a difference in preference was recognized (p<0.001). 4. Both parties regarded suutei chai as the most popular beverage for guests and family get-together occasions, but a higher percentage was seen among the provincials, while black tea was also regarded higher by Ulaanbaatar urbanites for such occasions than the provincials. Thus, a significant difference towards beverages in such a situation could be seen among the two parties (p<0.001). 5. Many of those who like black tea or coffee themselves seem to have selected the traditional suutei chai as their highest preference for guests and family get-together occasions.
An electronic nose is equipment imitating the human smell mechanism and evaluates the smell as the whole. The fundamental principle is the combination of the measurement of gas by some gas sensors with which the gas response characteristics differ and the multivariate analysis of information from these sensors. We added the trap tube to the measurement mechanism in a shimadzu electronic nose [FF-2A]. Using this trap tube, we got measurement sensitivity higher than before by concentration of sample gas, and reproducibility and distinctiveness higher than before by removal of humidity. And we introduced the concept of a vector into analysis. Using this analysis method, we realized dividing the smell into quality and strength and expressing them numerically, and realized bringing the strength of a smell close to human sense. We performed evaluation of smell in relation to food and drink field using FF-2A, and in this review, we introduced the example of comparative evaluation of the smell of the Japanese tea with which grades and places of production differ, yogurt, and wraps for foods.