We examined the effects of the concentration and molecular weight of collagen peptide (CP) added to rice flour cake on its taste and physical properties based on the density of cake batter, properties such as specific volume, weight variation, and texture as well as the appearance and sensory evaluation of the cake. Three types of CPs isolated from porcine skin, namely, CP1000, CP5000, and CP10000, with molecular weights 1.1, 5.4, and 10 kDa, respectively, were investigated. We found that the addition of 2% (w/w) CP5000 resulted in a cake batter of least density and improved the color, sweetness, softness, and moistness of the cake. Further, these cakes were easier to swallow and showed a higher overall palatability than cakes without CP5000. Based on these findings, we concluded that the use of CP of medium molecular weight, consisting of both low and high molecular weight fractions, and at 2% (w/w) concentration was needed to make puffed and delicious rice flour cake.

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Effects of various physical properties of gels on the physical properties and sensory characteristics of mixed sol-gel samples were investigated.
Mixed sol-gel samples were prepared using cubed agar gels with a thickening liquid. Four agar gel samples with different molecular weights were prepared: Urutora, Yamato, UP, and Gelatin kanten. The thickening liquid was prepared using commercial thickeners at three levels of thickness (mildly, moderately, and very thick).
The textural measurements showed that the hardness, adhesiveness, and cohesion of the mixed sol-gel samples depended on those of the gels. The adhesiveness and cohesion of the samples increased as sol thickness increased. The sensory characteristics of mixed sol-gel samples did not depend on those of the gels. It was conjectured that they were affected by the interaction between the gel, sol, and saliva during the chewing process.

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The gluten protein composition of wheat flour has a large influence on the quality as well as texture of the bread produced. In this study, we examined the effect of gluten protein composition on bread bolus texture during consumption. We substituted part or all of the commercially available wheat standard gluten (SG) for acid soluble gluten (ASG). We then prepared five types of reconstituted wheat flour with different gluten protein compositions, and made bread from each of these flours. Breads made using flours with high and low ASG substitution ratios did not differ with respect to hardness, but showed differences in cohesiveness. As the ASG content increased, simulated bread bolus hardness and adhesiveness decreased, as did the yield stress of the bread powder dispersion liquid. Based on a sensory evaluation, bread made with flour containing 100% ASG was softer and formed more coherent bread boluses than did the control bread (SG 100%). These results indicated that the gluten protein composition of wheat flour effects bread bolus texture during consumption.

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The emulsification properties of eggs allow them to readily mix with fats and oils. Moreover, their heat-induced gels have specific soft textures. However, to the best of our knowledge, the effects of adding fats and oils to liquid egg during the cooking process have not been studied so far. In the present study, we investigated the effects of heat on the rheological properties of two types of liquid egg mixtures, one with milk fat cream and the other with rapeseed oil, and their heat-induced gel structures and textures. We found that the dynamic linear viscoelasticity measurements at 10°C were relatively uniform for the liquid egg-milk fat cream mixture and highly variable for the liquid egg-rapeseed oil mixture, while those at 80°C were highly variable for the former and relatively uniform for the latter. When liquid egg was heated with milk fat cream or rapeseed oil in an omelet-like form, the resulting gel showed a porous structure, as evidenced by scanning electron microscopy. Texture measurements and sensory evaluations demonstrated that heat-induced liquid egg gel with milk fat cream exhibits vulnerable properties. Thus, the addition of milk fat cream or rapeseed oil to liquid egg altered its rheological properties, both during heating as well as during the formation of the heat-induced gel structure, and generated a unique, vulnerable, and flexible, texture.

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For different types of water used to brew green tea, the taste of the tea infusion was compared. Hard water is generally considered unsuitable for the leaching of green tea, and leached tea using Evian water, which had high hardness, had the strongest umami intensity as detected by taste sensors.
Adjusting the hardness of water using CaCl₂ had no effect on umami intensity. However, using it in combination with CaCO₃ influenced umami intensity in a manner dependent on the concentration of CaCO₃.
Using the green teas that were leached with Evian water and Crystal Geyser, a sensory evaluation was carried out using a three-point comparison method.
Green tea was leached with Evian water was significantly preferred.
Using an artificial hard water, tea that was leached with Evian water was measured in a sensory and taste sensor evaluation.
The taste of the two teas was similar.

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Fifty-four panellists aged 20-60 years each cooked 4 dishes using both gas and induction range cookers. The objective was to compare the flavour of the dishes and the cooks' satisfaction based on operating function and feelings of relief and achievement. Sautéed vegetables, grilled fish, ‘chawan-mushi’ and deep-fried chicken were cooked, and the panellists reported their satisfaction levels using a scale ranging from -2 to 2. The flavour of the dishes was also evaluated. With respect to the cooks' satisfaction, grilled fish, sautéed vegetables, and deep-fried chicken, cooked using a gas range, received significantly high scores. The cooks' satisfaction was mainly based on ability to control heating power as desired while watching the gas flames. Chawan-mushi cooked using an induction range cooker also received a significantly high score. The reason for this was that constant temperature was easily controlled. The panellists were satisfied with cooking when they could control the heat as desired. However, overall, gas was preferred over induction heating for cooking all 4 dishes.

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The sensory profile of fresh rice bran oil flavour was determined in comparison with those of soybean oil, canola oil, corn oil, and palm olein oil. Eight trained panellists evaluated the overall flavour intensity of four types of oil (rice bran oil, canola oil, corn oil, and palm oil) by time-intensity (TI) assessments, using soybean oil as a maximum reference sample. The obtained TI curves and TI parameters demonstrated the dynamic characteristics of flavour intensity of each sample during eating. The flavour intensity of rice bran oil was moderate; however, it decreased rapidly and consequently did not last long. The flavour attributes were also assessed qualitatively by nine trained panellists. They were asked to describe the flavour of each sample by selecting perceived flavour terms out of 35 candidate terms. The data were assessed using a correspondence analysis, and the flavour map of the oil sample was obtained. The characteristics of rice bran oil included a sweet flavour and rounded aroma.

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