Histamine release by granulocytes is a critical event in the induction of type I allergy. We investigated the effects of four different fruit vinegars made from yama-budo, haskap, blueberry and pomegranate on histamine release by the basophilic leukemia cell line RBL-2H3. Results clearly indicated that these fruit vinegars, especially pomegranate vinegar, have potent inhibitory effects on histamine release. We then performed adsorption chromatography with Diaion HP20 to estimate the bioactive components in pomegranate vinegar; the fraction eluted by 50% ethanol (EtOH) showed the most potent suppressive effect. Next, we subjected the 50% EtOH-fraction to liquid-liquid division with ethyl acetate (AcOEt), and suppressive activity was observed in both the water and AcOEt layer fractions, indicating the existence of multiple bioactive components. Furthermore, suppression of histamine release by each fraction was almost completely abolished by treatment with polyphenol adsorbent polyvinylpolypyrrolidone. These results suggested that the pomegranate vinegar contains multiple polyphenol compounds involved in the suppression of histamine release by granulocytes.

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The present study aimed to clarify the effects of soluble tannins from astringent persimmon on the qualities (color, texture and astringency) of pudding. We compared the qualities of pudding made with the astringent paste or juice and non-astringent paste from persimmon. As a result, puddings were dark in color when the astringent paste or juice of persimmon was added. Also, the sensory analysis of pudding appearance, color, smoothness and food texture showed increased values with the addition of the astringent persimmon juice. Further, the astringency of the paste and juice was disappeared by mixing with evaporated milk and egg during pudding manufacturing. It is concluded that the astringent persimmon juice is the most suitable for the manufacturing of pudding using astringent persimmon.

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We report here on the development of a fermented lactic acid beverage using syrup made from non-standard persimmons (Diospyros kaki ‘Fuyu’). BFRI 380-7, which was isolated from persimmons, was selected from growth assay results in persimmon syrup medium. BFRI 380-7 was identified as Lactobacillus plantarum. Furthermore, lactic acid bacteria (LAB) strains (including BFRI 380-7) that were capable of fermenting persimmon syrup exhibited tannase (tannin acylhydrolase) activity. BFRI 380-7 was optimally cultured at a temperature of 30°C and 4 to 6 days incubation time, and lactic acid production was the highest at a syrup concentration of Brix 30. Fermented persimmon syrup (30°C, 5 days) contained 1.1% lactic acid and LAB at 4.8×10⁸ CFU/ml. We successfully produced trial products of the fermented lactic acid beverage using BFRI 380-7 from persimmon syrup without milk components.

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In this study, a newly developed heating system, which consisted of superheated steam and hot water spray (Aqua-gas) treatment, was applied to sweet potato leaves. Upon initiation of Aqua-gas treatment, the internal temperature of sweet potato leaves was immediately increased, and reached 95°C in 30 seconds. Notably, polyphenol oxidase (PPO) activity was not deactivated by short-term Aqua-gas treatment, while 5-minute treatment almost completely inactivated PPO activity. Moreover, the amounts of caffeic acid and 7 species of caffeoylquinic acids (CQAs) in sweet potato leaves after Aqua-gas treatment were significantly higher compared to leaves subjected to boiling treatment. Therefore, we propose that Aqua-gas treatment is a useful heating system to maintain the nutritional components such as CQAs.

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