The enzyme-infusion method is a new technique used to soften food ingredients without destroying their shape. We studied the change in number of bacteria widely used as food hygiene indicators during the　cooking process of vegetables treated by enzyme infusion in order to evaluate its safety. We chose boiled vegetables (burdock roots, lotus roots, carrots, taro and bamboo shoots) in broth as the food sample and measured the standard plate count, and numbers of coliforms, anaerobic bacteria, Clostridia and aerobic spore-forming bacteria. The standard plate count and number of coliforms detected in vegetables before parboiling (e.g., raw, washed, peeled or cut) decreased as the cooking process advanced. No bacterial indicator could be detected after parboiling at 75℃ for 1min. Furthermore, no increase in Clostridia was apparent in the process when the cooking ingredients were under vacuum or hypoxic. The results indicate that boiled vegetables in broth subjected to enzyme-infusion seem to be safe as long as parboiling is properly conducted.

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In order to enhance hydrophilic properties of fiber surfaces, polyester fabrics were treated with an atmospheric pressure plasma (APP) jet with three reactive gas sources; air, nitrogen and argon. The surface reflection spectrum and the tensile extension parameters showed that the plasma impact damage to the fabric was small. The wettability and the surface free energy of the single fiber surface were found to increase considerably after the APP jet treatment. The water wicking rate into the capillaries of the polyester fabric was promoted as a result of the decrement in the advancing contact angle of water on the fiber surface. In addition, the APP jet treatment increased the dyeability of dispersive dyes and the soil release by laundering for the polyester fabric. The above improvements in the functional properties of the polyester fabric were remarkable when nitrogen was used as a reactive gas source.

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To develop a practical teaching unit on dyeing for a one-credit senior high school home economics class, the standard conditions of dyeing practices reported in literature on teaching resources and dyeing studies were searched and the contents were analyzed. A dyeing experiment with the aim of utilizing waste onion skin, which has year-round availability, and a mordant with low environmental impact was developed. The onion skin needed to be extracted in advance. The dyestuff and mordant were prepared at 90-100℃ and room temperature, respectively, and were used at 100% and 6% o.w.f., respectively. Under optimal conditions, dyeing time was 20 minutes, including the time required to heat the dyestuff. Both dyeing and mordanting were done only once and created sufficient hyperchromic effect to dye the fabric. Post-mordant time was 10minutes, followed by a variable amount of time for the soaping process. The dyed fabrics were tested for washing and light fastness.

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Thearubigin (TR) has a wide molecular weight distribution, and the structure and formation mechanism have not been elucidated. The ethyl acetate-soluble fraction of a black tea infusion were applied to Sephadex LH20 chromatography in this study, and further TR fractions were obtained and analyzed by HPLC. The results show TR to be a fraction consisting of two components. The content of antioxidants was also measured during the manufacturing process for a black tea, with 40% showing radical scavenging activity.The radical scavenging activity of the ethyl acetate-soluble fraction changed during a black tea manufacturing process and decreased to approximately 20%.

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The joule (J) has been the only scientific unit of energy included in the International System of Units(SI) since the 1950s; nevertheless, the calorie (cal) is still commonly used as a unit of energy in the field of nutrition and related areas. The unit used in any particular academic paper depends on the editorial policy of the publishing journal, so there is a great deal of inconsistency among academic papers in this field. We investigated in the present study the policy on energy units in 20 noted international journals and consider the reasons for each journal’s policy. We identified five types of journal policy after contacting the journals and looking up ‘energy intake’ in PubMed. Two journals have exclusively adopted kJ (MJ), three require kJ but also permit authors to provide kcal in parentheses where appropriate, one allows the use of kcal but also requires kJ in parentheses when kcal is used, twelve allow both kcal and kJ, and two have exclusively adopted kcal. Despite the general prevalence of using SI units in the modern world, kcal remains widely recognized as a unit of energy in the field of nutrition. We suggest four possible reasons for this. First, J did not originally refer to heat or potential energy. Second, the potential energy of food is measured by burning it and measuring the resulting increase in the temperature of water in a process directly related to the definition of cal. Third, cal is easy for the general public to understand. Fourth, cal is the unit most commonly used by the general public in daily life, and therefore must be adopted in field studies.

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