Superheated steam was applied to food processing because of advantages that include efficient heat transfer by latent heat and the prevention of product oxidation. Superheated steam solves problems such as water absorption and the dissolution of solid content from foods caused by hot water or saturated steam heating ; however, it causes low product yield due to its high drying capacity. In order to extend the application of superheated steam to food processing, 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 was 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, especially with cold materials. Fresh vegetables have been pasteurized effectively with little change in texture by heating with this system. 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. This system is currently used in the food industry for cooking potato salad, preprocessing meat, and in the pasteurization of fish products in Japan.

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In our earlier studies, 445 Japanese texture terms were collected from questionnaires administered to food scientists/technologists and interviews with texture researchers. In the present study, foods associated with the 445 Japanese texture terms were collected and analyzed. Terms that have the same meaning but are represented by different Chinese characters and onomatopoeic words that are derived from the same sound were classified into same term groups. A total of 271 term groups were formed in the study. Eighteen trained descriptive panelists were asked to write down food items associated with each term group. As a result, a comprehensive pool of 935 kinds of food associated with the texture terms was developed, and the data was submitted for correspondence analysis to understand the structure of Japanese texture vocabulary. The dimension 1 contrasts fracture versus fluidity terms. The dimension 2 can be interpreted as the axis related to fluffiness and airiness. The data obtained in this study can be applied to preliminary lexicon sources of descriptive sensory evaluation and can provide useful clues to the international understanding of Japanese texture terms.

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A method of predicting deoxynivalenol (DON) concentrations in wheat flour was developed using fluorescence fingerprinting (FF), which is also known as excitation-emission matrix. A partial least square (PLS) regression model was built based on FF values at various wavelength conditions and reference values for DON concentrations were measured by chemical analysis. The model showed good fitting to the validation dataset with R²=0.983 and SEP=1.4 ppm. The absolute values of the regression coefficient for the calibration model were significantly high in the wavelength range of Ex 240-400nm and Em 500-600nm. To reduce the number of wavelength conditions for shorter measurement time, PLS regression was again applied to the FF values at the above limited wavelength conditions. The fitting values of the acquired model to the validation dataset were R²=0.977, SEP=1.6ppm, and were not significantly different from those of the first model. The results indicate that rapid and non-destructive prediction of DON concentration in wheat flour is possible using FF.

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White bread was heated in convection microwave ovens with multiple functions, including oven (Ov), grill (Gr), steam (Sm), microwave (Mw), superheated steam grill (SSG), and superheated steam oven (SSO) functions. The texture, water content, and browning of the heated breads were investigated. 1) Bread heated with superheated steam softened quickly, and the texture was both soft and crispy. The texture of bread heated with Sm at 180°C was soft. 2) The speed of browning using SSG was 2.5 times faster than with Gr, and that using SSO was 2 times faster than with Ov. 3) Based on a water distribution model system, the textural characteristics of SSG and SSO samples are caused by the rapid speed of drying and surface browning, and the high internal moisture content. 4) The hardening caused by heating using Sm was slow, but the texture of long-heated bread was the same as that using Mw.

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7S and 11S globulins are major components of soybean protein. We developed a new simple freeze-thaw method for crude fractionation of these proteins in soymilk. Raw, unheated soymilk was frozen at -30°C, and then thawed at 10°C for 24h. The freeze-thawed soymilk separated into two layers, and the weight ratio of the upper layer (UPL) and the down layer (DOL) was 3 : 2. By SDS-PAGE analysis, the ratio of 7S to 11S globulins was 1 : 0.14 in the UPL, and 1 : 1.7 in the DOL. We mixed UPL with DOL in various ratios, and tofu curds were made from these mixtures. The breaking stress of the tofu curd increased with increased DOL ratios. The curd made from UPL was soft and smooth, and a novel dessert-like product was made via coagulation with yuzu juice. Through sensory evaluation, the product made using only UPL was tasty. These results show that rough separation of 7S and 11S globulins in raw soymilk can be achieved by a simple freeze-thaw treatment, and can lead to the development of new food products.

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Much evidence suggests that tea has anti-obesity properties. Studies have been conducted using Goishi tea, a post-fermented tea produced in Otoyo town, Kochi, Japan. As previously reported by Miyamura et al. in 2008, Goishi tea has antioxidant and anti-arteriosclerotic effects. The present study investigated the influence of Goishi tea on visceral fat weight in diet-induced obese mice. Obesity was induced in C57BL/6J mice by administrations of High-Fat Diet (HFD) for 28 days. We assessed obesity by measuring body weight, blood glucose, triglyceride (TG), total-cholesterol (T-CHO), insulin, internal fat weight and adipocytokine levels. The 28-day study indicated that the body and lipid weights were substantially higher in the HFD group than in the normal diet (ND) group. Intake of Goishi tea was shown to inhibit adipose tissue enlargement. In addition, the level of adiponectin in the Goishi tea group was the same as in the ND group. Goishi tea was also found to control an increase in tumor necrosis factor-α and interleukin-6 in the HFD group. It was suggested that Goishi tea is effective for treatment of metabolic syndrome.

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