In order to quantitatively estimate the effects of membrane fouling and osmotic pressure on the performance of membrane separation systems, a concentration polarization equation and a membrane transport equation based on nonequilibrium thermodynamics were applied to membrane processes for liquid foods, and new mathematical models were proposed. These models were then applied to several membrane processes in the food industry, including an ultrafiltration process for cheese whey fractionation, a reverse osmosis process for fruit juice concentration, and a nanofiltration process for oligosaccharide purification. The efficiency of the membrane processes could be precisely expressed by the new models, and the validity of the models was demonstrated. Thus, some membrane processes in the food industry can be optimized by using these models, and their feasibility evaluation is described.

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The purpose of this study was to examine the effect of soup temperature on body thermal sensation, body temperature and heart rate. A randomized crossover study was performed in 13 healthy female university students (22.2 _mls00b1/ 3.2 years). After overnight fasting, the subjects ate hot soup (87 kcal, 70°C), cold soup (87 kcal, 10°C), or drank hot water (0 kcal, 70°C) in the morning on different days. Body thermal sensation, tympanic membrane temperature, oral temperature and heart rate were evaluated over a 60-min period after soup or water intake. The changes in body thermal sensation and oral temperature just after the intake of hot soup and hot water were significantly higher than those after the intake of cold soup. The change in tympanic membrane temperature after the intake of soup or water was not significantly different among all three samples tested. The change in heart rate just after hot soup intake was significantly higher than that with cold soup or hot water. The oral temperature just after soup or water intake is thought to represent a regional temperature, whereas tympanic membrane temperature is thought to represent the systemic temperature. Therefore, it was suggested that the change in body thermal sensation just after the intake of soup or water was not based on the systemic temperature, but on the regional temperature. Since the only distinguishing factor of the hot soup was a higher palatability, it was suggested that the change in heart rate after hot soup intake is related to palatable taste stimulation.

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We examined whether Japanese white salted noodles mixed with 6% esterified tapioca starch would be a suitable food for the elderly. Samples studied were noodles prepared with wheat flour which had been boiled for 10 min (MG10), and noodles with wheat flour that was partly mixed with tapioca starch and boiled for 10 or 13 min (CA10 and CA13, respectively). Physical properties of the food were assessed by moisture content, shape change, and penetration tests. Mastication was evaluated by electromyography while young (age, 23.3±/2.7 years) and elderly (age, 75.8±/7.3 years) subjects ate the same samples, and palatability was assessed by sensory evaluation. Results revealed the following: 1) CA10 and CA13 were found to have a smoother, softer, and more elastic texture than MG10, and were considered by all subjects to be easier to eat and more palatable. 2) CA13 had a higher moisture content than CA10. It was softer, less elastic, and easier to chew in the early stage of mastication, and was considered to be the easiest to eat. 3) Mastication and palatability differed between young and elderly subjects. Elderly subjects chewed samples for a longer period of time and considered CA13 to be the easiest to eat with the best palatability. The young subjects also considered CA13 to be the easiest to eat, but found CA10 to be the most palatable and very chewy due to its dense firmness. 4) CA13 was considered by the elderly subjects to be the easiest to eat, despite its chewy consistency. Therefore, CA13 is likely useful in preventing masticatory hypofunction as it is a suitable food for the elderly.

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In order to isolate ingredients with lipase inhibitory activity in the ethanol extract of Cassia mimosoides L. var. nomame Makino, fractions were collected using liquid column chromatography and hig-performance liquid chromatography. This resulted in the isolation of ingredients I and II. Structural analysis showed that ingredient I was a known condensed tannin dimer. In contrast, ingredient II was found to be a novel condensed tannin trimer, but its final structure and stereostructure could not be successfully determined. Measurement of lipase inhibition activities showed that ingredients I and II had 50% inhibitory concentrations of 10 μg/mL and 0.8 μg/mL, respectively. Thus, it was confirmed that ingredient II had strong lipase inhibitory activity.

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Rice washing is an essential process for the removal of remaining bran from the surfaces of rice grains. The effect of NaCl on the removal of bran from milled rice grains by a water-based soak-washing process, of which the milling yield was 70%, was evaluated. In the soak-washing process, fats, fatty acids, and the off-flavor of aged rice grains were effectively reduced by the addition of NaCl into the water. This effect was also observed with a hand-washing process. This reduction can be attributed to the overall effect of at least the two following factors: the NaCl-induced decrease in interfacial tension at the bran-water interfaces in aqueous solution, and the repression of water uptake by rice grains under high concentrations of NaCl.

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We investigated the production of γ-aminobutyric acid (GABA) in bran obtained from the polishing of mules barley or mochi barley grains. This bran had high GABA production capability in glutamic acid solution in the absence of pyridoyxal phosphate. This might be because there is a high ratio of holo-type to apo-type glutamate decarboxylase in the bran from mules barley and mochi barley.

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Leaves of nine Okinawan sweet potato cultivars (Ipomoea batatas L.) and two comparable sweet potato cultivars were examined for their ability to induce nitric oxide (NO) production in LPS-stimulated RAW264.7 macrophages. All of these varieties suppressed nitrite production, an index of NO. In addition, the sweet potato leave extracts decreased the amount of nitrite ions generated from NOR3, an NO donor, indicating that they have NO-scavenging activity. This NO-scavenging activity of sweet potato leaves was correlated with the total amount of polyphenol and its main constituents of caffeoylquinic acid (CQA) derivatives, such as 5-monoCQA, 4,5-diCQA, 3,5-diCQA, 3,4-diCQA and 3,4,5-triCQA. Therefore, the CQA derivatives may be responsible for the NO-scavenging activity. This study demonstrated that sweet potato leaves may be promising functional food materials for preventing various inflammatory diseases that cause excess NO production.

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