A new oven system (Aqua-gas^TM) using superheated steam and micro droplets of hot water, has been developed. In this system, a mixture of superheated steam and hot water is achieved under normal pressure by spraying pressurized boiling water into a heating chamber through a nozzle. It was found that Aqua-gas has a higher heat transfer rate than ordinal superheated steam. The moisture content of the food product processed with this oven system can be controlled by regulating the amount of micro droplets used in the superheated steam.
In order to assess the basic cooking and processing properties of Aqua-gas treated food materials, a comparison between Aqua-gas treatment and boiling and steaming used as conventional cooking methods was undertaken using broccoli, green soybeans, Japanese radish, taros and carrots as test materials. The following results were obtained :

(1) The record of the heat transfer : When treated by Aqua-gas, the speed of the temperature rise at the central part of the materials at early stage of cooking is higher than when treated by conventional boiling (start cooking in cold water) and steaming, making the heat transfer highly coefficient.

(2) Moisture : No significant difference was recognized between the percentages of the moisture content of the materials treated by “Aqua-gas”, and those of neither conventionally “boiled” nor “steamed” materials.

(3) Color : Green vegetables such as broccoli and soybeans in AQG heating has higher score in a* value than steaming. But no such effect could be found from the scores of red carrots, white Japanese radish and taros.

(4) Texture : Vegetables like Broccoli and soybeans need little time to be processed by Aqua-gas heating. The texture of the cooked vegetables is between the textures of the boiled (tender) and the steamed (less tender than well-boiled), and was evaluated as “just right” by the evaluation of sensory testing.

  As for the vegetables that require relatively longer cooking time (longer than 10minutes), however, the texture of the Aqua-gas processed vegetables (e.g. Japanese radish, carrots and taros) was softer than that of the boiled and⁄or steamed.

(5) Nutrition information : In case of Aqua-gas heating, the levels of amino acids, such as alanine, aspartic acid and glutamic acid that indicate the level of sweetness, were higher than after boiling. The levels of amino acids, such as arginine that presents bitterness, were lower after conventional steaming. And the result of the sensory testing made it clear that the food processed by Aqua-gas heating were rated as the sweetest and the most tasteful.

  As for minerals and total vitamin C, Aqua-gas heating also controlled the reduction of the total amount of the minerals, and the loss of vitamins, as well.

(6) Application of Aqua-gas heating for preliminary heating of taros : As for the sensory testing of taros, a significant difference between Aqua-gas heating and non preliminary heating was not observed in overall evaluation such as the texture of the foods, and the comprehensive evaluation of taste, as well. Therefore Aqua-gas heating could be expected to replace preliminary heating.

View full abstract

  Exercise and nutrition are absolutely necessary for health promotion or enhancing athletic performance. On the other hand, physical activities and food situation affect nutritional status and physiological function.
  In Japan, exercise induced anemia (sports anemia) was observed in the late 1950′s., and this symptom was improved by increasing dietary total protein and⁄or animal protein intake levels. Nowadays, protein fat carbohydrate ratio is approximately 15:25:60 which is suggested for athletes. In case of maintaining body weight, the dietary method of increasing all foods in proportion to the energy intake seems to be suitable. Body weight reduction by exercise is more effective than by dietary restriction even when dietary condition is equal except for energy.
  It is well known that prolonged bed rest or weightlessness cause various atrophies and decreasing physiological function. After the Great East Japan Earthquake, disuse syndrome under worsened food situation happened as well as after previous earthquakes. In these cases, relatively-frequent physical activities are recommended than relatively- large amount of exercise.
  Recently in the world, there are some problems such as double burden of malnutrition in developing countries and obesity people who consume too much junk food or soft drinks, etc. In response to becoming diversified lifestyles, it is considered that roles of eating habits and physical activities will be more important.

View full abstract

  I and my students have developed some fish sauces made from puffer, whale and sea urchin gonad as the local specialties of Shimonoseki city in west Japan. These sauces were commercialized. Antioxidant actives of these sauces were measured by using chemiluminescence, ESR (electron spin resonance), ORAC (oxygen radical absorbance capacity) and HORAC (hydroxyl radical averting capacity) methods. As the results, these sauces indicated the high antioxidant activities. Furthermore, these sauces were researched by the next-generation food functional estimation method, i.e., the new simultaneous measurement method using cellular signal transduction mechanisms. This method means the simultaneous measurement of chemiluminescence and fluorescence by LED light indicating superoxide anion radical generation and intracellular calcium ion concentration, respectively, of neutrophil-like HL60 culture cells. It was found that some sauces indicated the anti-inflammatory activity in addition to antioxidant activity. On the other hand, I and co-researchers investigated the supply of high quality frozen raw fish by a quick freezing method using alcohol brine. The whole body of Japanese horse mackerel was used. Alcohol brine freezing at -25°C was compared with air freezing at -20°C. Quality of fish meat was analyzed using K value as an indicator of freshness by HPLC, pH, TBARS value as an indicator of lipid oxidation, remaining ethanol by GC/MS and sensory test. As the results, it was indicated that the fish meat frozen quickly by alcohol brine method was superior to that by air freezing.

View full abstract

  Japanese rice consumption has been on a declining trend. In 2006, it fell to approximately half of its 1960 level. A major factor in this decline has been the switch to a more western style dietary lifestyle with higher intakes of animal products and fat, which have reinforced the decrease in rice consumption. In the present paper, as an aid to thinking about how rice consumption can be expanded, the author introduce a number of new technologies concerning rice and rice flour. For example, new genetic traits have been introduced that have created rice varieties with new functions. Among these are low-amylose rice, which doesn't become hard even when it gets cold, and low-gultelin rice for patients with kidney diseases. Pre-washed rice was developed from the two standpoints of improving convenience when cooking rice and preventing water contamination from rice-washing water. Aseptic packaging technology was developed in order to make it easy to eat tasty pre-cooked rice. A new type of rice cooker has appeared equipped with a temperature program to draw out the full sweetness and deliciousness of cooked rice by activating the rice's enzymes during cooking. Moreover, technology for grinding rice flour into an extremely fine powder so that it can be used for the same purposes as wheat flour has gone on sale commercially. As a result, bread is now baked using rice flower and breads with new textures and gluten-free bread for people with wheat allergies have also appeared. Thanks to a slew of innovative technological developments such as these, an expansion in rice consumption can be expected in future.

View full abstract

  The purpose of this study was to investigate the relationship between the eating habits and unidentified complaints of high school students, in order to show the possibility that unidentified complaints were an operant reinforcer to improve their eating habits.
  Meal balances were calculated from the Food Balance Guide. The eating habits of both boys and girls were not well-balanced that intakes of staple food, side dishes and fruits were not enough, and intake of confectioneries/soft drinks was excessive. In the case of boys, the overintake of confectioneries/soft drinks was related to deficiency in meals. Girls had significantly more symptoms of unidentified complaints than boys.
  The relation between the eating habits and unidentified complaints was clear among the boys. Overintake of confectioneries/soft drinks was related to the frequency of irritation. The deficient intake of staple food caused headache. The shortage of side dishes caused postural hypotension, stiff necks and irritation. These results suggested that the unidentified complaint could be improved by reducing the intake of confectioneries/soft drinks and taking properly staple food and side dishes in boys.

View full abstract

  Tartary buckwheat flour is considered to be a good health food with a new physiological function, because it includes more rutin, an antioxidative component, than the ordinary buckwheat flour. However, by containing rutinase, it has more bitterness than the ordinary buckwheat flour. Therefore, we used the tartary buckwheat flour whose rutinase was deactivated by a heat-moisture treatment in this study, and a series of cookies were made by changing the added amount of the tartary buckwheat flour in order to clarify its optimal ratio as well as its effective use and aptitude from the viewpoints of improving the physical properties, palatability and antioxidative activity of the cookies.
  To make each of these sample cookies, 100g of powder, which contains 0, 10, 30, 50 or 70 wt% of the tartary buckwheat flour added to conventional flour, and a certain volume of butter, sugar, and egg, were mixed, molded and baked for 14 minutes at 170°C. Their breaking strengths were measured as the physical property and their volumes were measured by using the rapeseed method. For the appearance evaluation the L^*, a^* and b^* values were measured, and their overall qualities were additionally evaluated by a sensory evaluation. The peroxyl radical scavenging activity was measured by the chemiluminescence method, and the antioxidative activity was compared based on the IC₅₀ value.
  As a result, the volume expansion was reduced by adding the tartary buckwheat flour to the cookies, and the rupture stress significantly decreased by adding more than 30 wt% of it. The L^* value decreased, the a^* value rose, and a red color became darken by increasing the added amount of the tartary buckwheat flour. Moreover, the IC₅₀ value decreased and the improvement of the antioxidative activity was observed though the preference of the color decreased. The sample with 50 wt% of the added tartary buckwheat flour was significantly favored in the sensory evaluation.
  Consequently, the addition of the tartary buckwheat flour to the cookies was found to be an effective method. It was possible to improve the taste and the texture by adding the tartary buckwheat flour by 50 wt%, and to allow the cookies to have an excellent antioxidative activity.

View full abstract

  We developed a verbal expression for a visceral sensation as a subjective evaluation with regard to the feeling of satiation. The purpose of this study was to examine the change in the score by the progress of time and reproducibility of this verbal expression for a visceral sensation. The feeling of satiation in 33 healthy adults was measured by using the VAS (visual analog scale) and a verbal expression for a visceral sensation on 17 items before and six hours after a standard meal. The result of a feeling of satiation (VAS) was significantly high after feeding until 300 minutes in comparison with fasting score (F (8,216)=148.4, p<0.01). The verbal expression of a visceral sensation was significantly high after feeding until 180 minutes in comparison with fasting score (F (8,216)=84.1, p<0.01). Furthermore, capacity and weight factor scores were classified into 3 patterns from the time required for the scores to return to the average score before meal. The pattern that decreased in section from 180 to 240 minutes was similar to the pattern by scintigraphy at all discharge time. It was suggested that the visceral sensation expression captured the information on the stomach and viscera.

View full abstract

  We studied the effects of corn oil and perilla oil intake by rats during pregnancy and lactation on the composition of the stomach contents and plasma lipids concentration in their pups. Two groups of dams were fed either a corn oil diet (CD) or a perilla oil diet (PD) during their pregnancy and lactation. On days 8, 21 and 33 after birth, two pups each from the litters of all dams were killed and their blood and stomach were collected. A long chain polyunsaturated fatty acid (LCPUFA; C_20-22) not presented in the dams diet was detected in the stomach breast milk of both groups. Although the n-3 fatty acids of LCPUFA in the stomach of the PD group was higher than that of the CD group, no significant difference in the arachidonic acid (AA; 20:4) and docosahexaenoic acid (DHA; 22:6) was observed between the two groups. The plasma lipid concentration in the pups of the PD group was lower than that of the CD group, but there was no significant difference in the two groups after weaning. Therefore, α-lindenic acid (ALA; 18:3) in the PD was synthesized into eicosapentaenoic acid (EPA; 20:5) and DHA in the dam's body and added to the breast milk, which indicated that the plasma lipids concentration in the pups nursed by the dams fed the PD decreased during lactation.

View full abstract

  The taste preference for various sour dishes, prepared by the addition of one of the purified organic acids as the major sour component, was studied by a sensory evaluation panel comprised of female college students. The sour dishes were sushi rice, Japanese sunomono salad, tofu with a dip of ponzu shoyu (a mixture of citrus-based sauce and soy sauce), honey juice and yogurt drink, and the selected organic acids were gluconic acid, citric acid, acetic acid and lactic acid. Together with citric acid as the results, gluconic acid was significantly preferred over the other organic acids in the yogurt drink. Also, when gluconic acid was added to vinegary dressing at the final concentration of 10% (W/V) as the new recipe (half the amount of salt), there was no difference in terms of preferences of sushi rice between a normal recipe having little gluconic acid and the new recipe. Gluconic acid is a food additive, therefore, the manufacturing study of brewed vinegar, containing a large amount of gluconic acid, as a food was carried out, and by using Gluconacetobacter xylinum and a rotary shaking culture, gluconic acid was accumulated to 9% (W/V) in a 220hr cultivation, and the remaining acetic acid was negligible in the medium. These results suggest that it is possible to produce a new sushi vinegar (vinegary dressing for the rice) having a low salt content and pre-biotics (gluconic acid), but that it is difficult to offer gluconic acid as a mere acidifier of food additives without using other organic acids.

View full abstract

  To brush up dietician skills, a survey of a comparative examination between the habits of eating using a Japanese Food Guide Spinning Top, and others and the awareness of dietician college students was carried out.
  Examination using the Japanese Food Guide Spinning Top, linked others, but did not indicate an intake situation for each body type.
  There were many problems at each body type. To improve the college students motivation to be a dietician, it was suggested that it is important to emphasize to them that meals can be fun. It is essential that diet modifications in each female student needs to be made.
  It is necessary that we continually give them regular education using the Japanese Food Guide Spinning Top, with the purpose of making them conscious about diet. Practical nutrition education in combination with a diet survey, habits on eating and awareness will help them correctly perceive the problem.

View full abstract