In recent years, numerous attempts have been made to reduce the sugar content of processed foods to meet consumer demand. The aim of this study was to produce cookies without added sugar through rice koji fermentation combined with the addition of food enzymes. Rice koji prepared from the yukikomachi variety, which exhibits high enzyme activity, was the most suitable among five tested white koji molds for cookie production. The thickness and expansion rates of cookies prepared using rice koji and food enzymes were lower than those of sugar-containing cookies (control). However, no significant difference in cookie diameter was observed, indicating a greater spread in experimental cookies. Compared to the control, the L* values for the cookies were significantly lower, whereas the a* and b* values were higher, consistent with increased browning. Experimental cookies were markedly softer than the control cookies, and brittleness differed significantly among treatments. Differences in sugar composition were also observed. Further, total free amino acid and GABA contents were approximately 20.5–25.8-fold and 1.4–1.7-fold higher than the control, respectively. Additionally, the experimental cookies had fewer calories, higher crude protein levels, and lower carbohydrate levels compared to the control cookies. These results suggest that cookies prepared with rice koji and food enzymes may serve as a healthier alternative.

Ice cream was prepared using both a tabletop and a commercial batch freezer, with identical ingredients and formulations, to compare overrun and microstructure during the freezing process. Both machines exhibited similar trends in overrun throughout the manufacturing process. Peak overrun was observed when the ice cream temperature reached approximately −4 C. Although the peak overrun values differed between the machines, a significant positive correlation was observed. Cryo-scanning electron microscopy images showed that air cells and ice particles became finer as freezing progressed in both machines. These findings indicate that tabletop ice cream machines are suitable for fundamental research, as they exhibit freezing behavior similar to that of commercial machines. The results also suggest that the maximum overrun values for commercial machines may be estimable based on data obtained from tabletop machines.

This study aimed to develop konjac glucomannan gels with novel mechanical properties by modifying the gel network structure. Five types of scallop shell–derived particle gelling agents, with varying particle diameters (1.4 mm < D_a ≤ 4.0 mm, 910 μm < D_b ≤ 1.4 mm, 530 μm < Dc ≤ 910 μm, D_d ≤ 310 μm, and D_e ≤ 150 μm), were used as alternatives to conventional gelling agents (e.g., calcium hydroxide). Konjac gels with an inhomogeneous structure, characterized by cloudy and translucent regions, were obtained using gelling agents with large particle sizes (530 μm < D_a, D_b, and D_c ≤ 4.0 mm). Puncture resistance, surface pH, and internal pH were measured. The cloudy regions exhibited puncture resistance values ranging from 0.63 N to 0.90 N, whereas the translucent regions showed values below the measurement accuracy of 0.05 N. The pH values showed no significant difference (11.62 ≤ pH ≤ 12.34) among all samples regardless of the measurement regions.Although the pH values of the translucent regions were sufficiently alkaline for gel formation, puncture resistance showed markedly low values. Two-bite texture analysis showed distinct mechanical property differences between the inhomogeneous and homogeneous konjac glucomannan gels.

Chewing sounds are an important component contributing to the perceived "deliciousness" of food. This study clarified the tonal and emotional evaluations elicited solely by chewing sounds, excluding the influences of taste, aroma, and texture. The participants comprised 25 employees of a company affiliated with the first author. A total of 22 types of food, including frozen desserts and sweets, were evaluated by the SD method. Principal component analysis revealed that 83.7 % of the tonal evaluation variance was explained by the first principal component, which ranged from "hard/cracked" to "vague/weak". Similarly, 79.9 % of the emotional evaluation was explained by the first principal component, which ranged from "motivating/arousing" to "depressed/calm". A strong correlation was observed between the scores of the first principal component and the tonal and emotional evaluations (r=0.984). Cluster analysis grouped the chewing sounds into four clusters: high arousal, semi-arousal, semi- subsidence, and high subsidence. Metallic and hard sounds tended to evoke feelings of motivation and arousal, whereas weak and vague sounds were associated with depression and subsidence. Spectrogram analysis indicated that metallic and hard chewing sounds produced high sound pressure levels in high frequency bands over short durations, while weak sounds produced low sound pressure levels in low frequency bands over longer periods. These findings suggest that differences in food structure affect both the tonal and emotional perceptions of chewing sounds.

To elucidate the potential novel functions and health benefits of red beet, the present study compared the antioxidant properties, polyphenol contents, and flavor characteristics of kimchi prepared with red beet and Japanese radish. Samples of red beet kimchi and Japanese radish kimchi that had been fermented for 0, 3, 7 and 14 days were analyzed. In all samples, DPPH radical scavenging activity and total polyphenol content were consistently higher in red beet kimchi than in Japanese radish kimchi. The results of sensory evaluations revealed that red beet kimchi was sweeter and less acidic than Japanese radish kimchi, suggesting that red beet kimchi may be preferred by people who dislike acidic kimchi. Furthermore, red beet kimchi had higher functionality and appeared to be more palatable than Japanese radish kimchi.

Waxy barley contains high levels of dietary fiber and calcium, while amaranth is rich in dietary fiber, calcium, magnesium, iron, zinc, and vitamin B6, nutrients that are often deficient in the Japanese diet. To elucidate the optimal combination of cereal grains with high acceptability for promoting habitual consumption and nutritional benefits, the effects of various grains cooked with white rice on color, flavor, texture and taste were evaluated using a colorimeter, gas chromatograph-mass spectrometer (GCMS), texture analyzer, and by sensory evaluation. The flavor of cooked waxy barley is distinguishable from other grains, mainly because it is rich in aldehyde such as hexanal and ketones such as 3-octen-2-one. Addition of black rice improved the appearance of cooked assorted grains including waxy barley and amaranth. Waxy grains increased the stickiness. The addition of waxy proso millet, which is bright yellow in color, may further improve the flavor of the cooked grains. A mixture of grains comprising 30 % waxy barley, 5 % black rice, 3 % amaranth, 3 % waxy foxtail millet, and 3 % waxy proso millet cooked with white rice has high palatability for consumption as well as nutritional and health benefits and is well suited for habitual consumption.

The purpose of this study was to clarify the conditions under which gluten-free and additive-free breads can be prepared by mixing two types of rice flour. Rice flour of “Mizuhochikara,” a variety suitable for making rice-flour bread, was mixed with rice flour from either “Yawaramaru,” a non-glutinous variety with a high amylopectin short chain ratio, or “Yawakoimochi,” a glutinous variety with a high amylopectin short chain ratio. When “Yawaramaru” rice flour was used, the specific volume was more than 4.0 mL/g at a substitution rate of up to 40 %. The firmness of bread made with 40 % “Yawaramaru rice” flour after 3 days of storage was about 18 % lower than that of bread made with “Mizuhochikara” rice flour only (p < 0.05). When “Yawakoimochi” rice flour was used, the specific volume was about 3.3 mL/g at a substitution rate of 20%; however, at higher substitution rates, the loaves had significantly less volume. The firmness of bread made with 20 % “Yawakoimochi” rice flour after 3 days was about 18 % lower than that of bread made with “Mizuhochikara” rice flour only (p < 0.01). These results indicate that using rice flour with a high percentage of short amylopectin side chains can suppress bread aging to some extent without the addition of additives such as thickening agents.