We evaluated the environmental impact of aseptically packaged chicken using ohmic heating. Ohmic heating is a method that directly applies electric power to food. CO2 emissions were determined for each stage and compared with retort-heated food products. Retort-heated foods were assumed to be packaged by two methods: retort pouches and canned food. Replacing cans with pouches reduced CO2 emissions by 64 %. CO2 emissions were reduced by more than 80 % by replacing retort heating with ohmic heating. Additionally, the characterized results of 13 environmental areas indicate that the substitution of canned foods with aseptically packaged foods using ohmic heating can potentially reduce the environmental impact by up to 88 %. Furthermore, in the quality evaluation, ohmic-heated foods retained the same or better quality and palatability as the retort-heated foods. Aseptically packaged food products using ohmic heating can be substituted for conventional retort heating methods to reduce the environmental impact without sacrificing palatability.
The present study describes the effects of prefreezing on drying rate, surface color, internal structure, and textural properties of kiwifruit treated with microwave-vacuum drying (MVD) under controlled-temperature conditions at 20, 30, and 40 °C. The prefreezing was effective in reducing the drying time in the MVD process under properly controlled temperature conditions. The MVD samples without prefreezing had the same level of low a* value (high greenness) as the freeze-dried sample, but the prefrozen-MVD samples showed a slight browning due to discoloration during thawing in an atmospheric pressure environment. The prefreezing suppressed sample shrinkage during the MVD process and allowed the formation of a porous structure with many large voids with thin walls. Thanks to this structure, the prefrozen-MVD samples showed textural characteristics similar to the freeze-dried sample, but the porous structure was not formed in the MVD at 20 °C, indicating that a high microwave power is required to generate a high enough vapor pressure to form the porous structure.
Hard water is softened because its use in everyday life can cause various problems in the living environment. However, existing water-softening methods have a number of drawbacks. Here we examined a new water-softening method involving atomization. Three concentrations of calcium-based synthetic hard water and a commercial natural hard water were prepared. Each hard water was sprayed into the atmosphere at 1 MPa from an atomization nozzle and then collected. Part of the collected water was recirculated, and the atomization treatment was continued. After the treatment, a white precipitate and fine bubbles were generated, the Ca2+ concentration and electrical conductivity decreased, and the pH increased. Then over time, the white precipitate increased slowly and the Ca2+ concentration decreased until finally it almost fell within the recommended range. This water-softening phenomenon was thought to be due to expansion of the gas-liquid interfacial area and generation of fine bubbles with atomization. This method is extremely simple and expected to show high versatility.
The regulation of enzyme activity in the production of various fermented foods using koji mold has been optimized in many ways, and few additional refinements are apparent. This study examined light as a modifiable factor with which to adjust the enzyme activities of koji. A previous study has shown improved saccharification of wheat bran with Aspergillus oryzae RIB40 under at least 8 h of darkness. In the work reported here, light exposure had no significant effect on the saccharification activity of A. oryzae RIB1187. However, light exposure for 8 h or more continuously decreased protease-specific activity in RIB1187, as was seen previously in RIB40. This information may help manufacturers to improve fungal enzyme production, processes, and facilities.
Lipid oxidation in food can result in the generation of off-odor compounds. We investigated the combined effects of α-tocopherol with rosmarinic acid and various antioxidants on the prevention and inhibition of off-odor formation. We added these combined compounds in a linoleic acid emulsion, followed by an oxidation reaction with 2′2-Azobis (2-methylpropionamidine) Dihydrochloride at 37 °C for 5 h. The hydroperoxide was measured by the ferric thiocyanate method, and the off-odor components were measured by gas chromatography. Median effect analysis was used to assess the combined effects. The results showed that the combinations of α-tocopherol with rosmarinic acid and caffeic acid exhibited a synergistic effect on inhibition of lipid peroxidation and some off-odor components, likely attributable to the catechol structure in these compounds. Interestingly, the combination of α-tocopherol and rosmarinic acid showed a potent synergistic effect on (E)-2-nonenal and (E)-2-octenal, indicating that the formation process of off-odor components may influence the combined effect.
This study aimed to evaluate the physiological functions of Asparagus officinalis L. fruit extracts with 70 % ethanol. The polyphenol-concentrated ethyl acetate (EtOAc) fraction of the asparagus fruit extract exhibited high inhibitory activity in vitro, against α-amylase, α-glucosidase, lipase, and angiotensin-I-converting enzyme compared to the other fractions. This fraction also exhibited an anti-proliferative effect on 3T3-L1 preadipocytes, and suppressed lipid accumulation and cell viability of 3T3-L1 adipocytes; it had no such effect on mature adipocytes. This suggests that the anti-lipid accumulation activity of this fraction was due to suppression of the differentiation of 3T3-L1 preadipocytes, and not direct suppression of lipid accumulation. The effect of the EtOAc fraction on 3T3-L1 cells might be partially attributable to luteolin. Thus, A. officinalis L. fruits contain polyphenols which can potentially prevent lifestyle diseases, with luteolin being a promising candidate.
Goldenberry leaves are widely consumed traditionally due to the multiple health benefits attributed to them. The objective of this study was to evaluate the effect of foliar application of salicylic acid (SA) at different concentrations during goldenberry cultivation on the physicochemical and nutraceutical properties of the leaves. The results showed that 0.5- and 1-mM SA treatments significantly increased the levels of total phenolic compounds, flavonoids, extractable phenolic compounds and proanthocyanins in goldenberry leaves. It also had positive effects on chlorophyll levels, although higher SA concentrations tended to decrease chlorophyll content. No SA treatment affected plant growth, pH, or acidity, however, a slight decrease in the total soluble solids content was observed. Proximate analysis revealed that SA treatment did not alter fat and ash content but increased protein content and decreased total carbohydrate content. Moreover, treatment with 0.5 and 1.0 mM of SA resulted in increased levels of proline and phytosterols and exhibited higher antioxidant capacity, attributed to their rich content of bioactive compounds, particularly phenolics. Additionally, 1.0 mM SA treatment enhanced the inhibitory activity of α-amylase and pancreatic lipase, indicating its potential in managing hyperglycemic conditions. These findings highlight the nutraceutical properties of goldenberry leaves and their potential utilization as a byproduct of goldenberry cultivation, warranting further research to explore their metabolite profile and maximize their benefits.
As part of our studies on the prevention of lifestyle-related diseases by processed foods, we evaluated the xanthine oxidase (XO) inhibitory activity of barley tea. The XO inhibitory activity of the tea (a hot-water extract of roasted barley) was not as potent as that of another roasted beverage, coffee. However, the activity of an ethyl acetate-soluble substance in the extract was significantly stronger than that in coffee. Purification of the substance revealed that pyrogallol was the most potent compound. After establishing a quantification method for pyrogallol in barley tea, we analyzed correlations between pyrogallol content, roasted grain color, and XO inhibitory capacity of barley tea. The findings suggest that the XO inhibitory activity of barley tea is related to the roasting degree and chroma b* of barley grains through the content of pyrogallol, although other active compounds may be present in barley tea.
The contents of a meal may affect postprandial performance, e.g., by causing drowsiness. Therefore, we investigated the effects of a low-carbohydrate meal (LCM) on drowsiness and performance. We evaluated postprandial drowsiness, wakefulness, and concentration level by eye tracking analysis, monitored blood glucose levels over time, and measured autonomic nervous system activity and cognitive function before and after the meal. In addition, participants subjectively evaluated their condition with a visual analogue scale. We found that the postprandial rise in blood glucose level was significantly lower after an LCM than after a high-carbohydrate meal (HCM), but the results of the eye tracking test showed no statistically significant differences between the LCM and HCM. However, it tended to decrease blink duration and increase pupil diameter and fixed gaze duration after the LCM compared to HCM. The findings suggest that postprandial blood glucose levels and the eye tracking indices were possibly related.
Raw soymilk separates into two layers upon freeze-thawing. We investigated the effects of high-temperature thawing (50–100 °C) on the freeze-thaw fractionation of soymilk. After freezing, the samples thawed at high temperatures separated into two layers with similar fractions as observed in samples thawed at low temperatures (10 °C). As the thawing temperature increased, the separation time of the samples thawed at high temperatures decreased by less than half, when compared to those thawed at low temperatures. The ratio of the weight of the upper layer to the total weight decreased as the thawing temperature increased. The 7S and 11S proteins in soymilk could be fractionated through high-temperature thawing, similar to that through low-temperature thawing. Protein denaturation did not occur upon fractionation at higher temperatures. These results suggest that raw soymilk can be fractionated even through high-temperature thawing and may contribute to the efficient production of freeze-thaw fractionated soymilk.
Brassicaceae vegetables contain glucosinolate (GSL), which is well known for its role in the plant defense system, bitter substances, and functional components. This study reported the GSL profiles of 18 GSLs in 14 Brassicaceae vegetables (kale, cabbage, kohlrabi, broccoli, cauliflower, komatsuna, pak choi, turnip, choy sum, Chinese cabbage, rutabaga, leaf mustard, leaf radish, and radish root) consisting of 64 cultivars grown in Japan. The GSL compositions showed specific trends among each species, and furthermore, there was considerable variation in the total and individual GSL contents among the cultivars and tissues of the same vegetable. Because each vegetable was grown under the same conditions, this variation was expected to primarily be due to the genetic background. It is desirable to collect additional data from commonly distributed cultivars to conduct more detailed studies on GSLs in Brassicaceae vegetables, such as investigating a negative correlation between GSL consumption and cancer risk.
Soy protein has been approved in Japan as a Food for Specified Health Uses to lower serum cholesterol. A foreign-made soy protein ELISA kit has been proposed for quantifying soy protein levels. However, acquisition of this foreign-made product is time-consuming, making the product inconvenient for soy protein quantification in Japan. Therefore, as possible alternatives, we evaluated two commercial domestic ELISA kits, both of which quantify soy protein and specific allergens for food-allergen labeling. In this study, we compared antibody reactivity and soy protein levels in soy milk using these three types of ELISA kits (one foreign-made and two domestic ELISA kits). Per the results, we found that commercial domestic ELISA kit-derived soy protein levels could be converted to the soybean protein levels obtained from the foreign-made soy protein ELISA kit, through multiplication by specific factors.
We assessed the bacterial diversity in five Alaska pollock surimi samples using 16S rRNA sequencing to plan the pre-processing of fermenting surimi. The viable bacterial count of the surimi samples was approximately 104-105 cfu/g. Phylogenetic tree analysis revealed that the surimi bacterial profile was dominated by phylum Pseudomonadota, with the dominant genera being Pseudomonas and Psychrobacter. Only one strain of spore-producing bacteria was isolated from the five surimi samples. These results suggest that pasteurization before inoculation of bacterial starters was necessary for stable and hygienic fermentation of Alaska pollock surimi.
Neuronal activity plays a key role in the development and maintenance of the central nervous system. In cultured cerebellar granule neurons (CGNs), activity deprivation by treatment with a low concentration of KCl induces neuronal apoptosis. We found that black pepper (Piper nigrum) oleoresin significantly increased the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide signal on activity-deprived CGNs, whereas piperine, a major compound in black pepper extract, did not. Consistently, induction of cleaved caspase-3, a hallmark of apoptosis was inhibited by black pepper oleoresin upon neuronal activity deprivation. These results show that black pepper oleoresin protects CGNs from apoptosis induced by activity deprivation, and suggest that components other than piperine might contribute to this effect.