Focusing on the gelatin/transglutaminase cross-linking reaction, we aimed to develop a preparation method for powdered fish oil as a sustained-release formulation. Various combinations of gelatin (containing transglutaminase) and emulsifiers were screened to obtain a high quality powder. The newly developed powder contained high amounts of lipids (74% of dry weight; 152mg docosahexaenoic acid/g, 41mg eicosapentaenoic acid/g); nevertheless, the powder exhibited good oxidation stability. As expected, the powdered fish oil showed slow-release properties in experiments in vitro. This novel powdered fish oil would therefore be useful for nutraceutical applications.

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For the effective utilization of food materials, the physicochemical properties and volatile compounds, as well the effect of water washing, of a thermocoagulation product recovered from brine used in salted-dried horse mackerel production were examined. The amount of recovered product by heat sterilization increased up to three weeks; thereafter, no notable increases were observed. Proximate composition analysis revealed the moisture, ash, protein and lipid contents of the product were 64, 16, 17 and 2%, respectively. Off-flavor compounds in the thermocoagulation product were mainly aldehydes and alcohols. Furthermore, it was determined that the salt concentration and volatile flavor compounds were reduced and color values (L^*) were increased by washing. These results revealed that the thermocoagulation product could be effectively reused as a food material after washing.

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For the purpose of promoting the utilization of venison as a functional food, we investigated the carnitine content and physical properties of venison subjected to different sous-vide (cooking by steam heating under vacuum) processing temperatures. The present work aimed to quantify free carnitine and acylcarnitine using liquid chromatography-tandem mass spectrometry. Compared to meat samples heated at 100℃, those heated at 80℃ showed a slow temperature increase and a low rate of weight loss. Moreover, heating at 80℃ resulted in greater hydrophilic L-carnitine and low molecular weight acetylcarnitine than heating at 100℃. On the other hand, levels of hydrophobic hexanoylcarnitine, myristoylcarnitine, and palmitoylcarnitine were greater at 100℃. Determinations of physical properties showed that samples heated at 80℃ were significantly tenderer than those heated at 100℃. Furthermore, sensory evaluation results showed that samples heated at 80℃ scored highly in the following three attributes：toughness (palatability); umami; and overall palatability. Based on these results, we propose that heating at 80℃ is more desirable with respect to functionality and palatability for promoting the utilization of venison as a functional food.

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The relationship between physical properties and water content of monolayers (Wm) and multilayers (MC) was investigated for baked white wheat flour products with different gelatinization levels at various temperatures (5, 20, 40℃). As the temperature increased from 5℃ to 40℃, the region of relative humidity (RH) for brittle narrowed to low RH and that for softening widened. Irrespective of the temperatures tested here, brittle occurred at low RH and hardening at middle-high RH. The RH region of brittle corresponded well to the RH region of Wm during the desorption process, whereas softening corresponded to the MC region. Especially, baked white wheat products with a high gelatinization level became harder at the RH region for MC, and softening started at the MC region. Therefore, the water contents of the Wm and MC regions may be intimately involved in changes in the physical properties of baked white wheat products, irrespective of the temperatures tested here.

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In an attempt to control the blood sugar increase that occurs after consuming cooked rice, we assessed the enthalpy and sensory and textural properties of κ-carrageenan-supplemented rice, and measured its effect on blood glucose in 13 fasting subjects. Samples were prepared by adding κ-carrageenan during cooking, (CP) or in gel form alone (CG) or in combination with CaCl₂ (CG-CaCl₂) to precooked rice. Subjects who consumed greater than 1.0% CP had significantly lower blood sugar levels after 15 and 30 min compared with subjects who consumed standard cooked rice (control). Blood sugar levels of 1.6% CP were only lower than in control after 45 min. The glycemic index (GI) of rice supplemented with greater than 1.0% CP was significantly lower than that of control, and glucose release decreased with CP supplementation greater than 0.5%. Glucose release and GI did not significantly differ between CG-CaCl₂ and control groups. Subjective and objective measures of texture property suggested that hardness significantly increased in rice supplemented with 0.5% CP.

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