Fresh perilla leaves (Perilla ocimoides L. var. crispa) were used to prepare the following five sample solutions : dark-reddish-purple Japanese apricot vinegar (DRP-JAV) containing lye (+lye), DRP-JAV prepared after removing lye, JAV solution of purified anthocyanin pigment (AN, hereafter), a buffer solution of purified AN, and an 18% salt-McIlvaine's (MI) buffer solution of purified AN. These sample solutions were stored for 60 days, examined of their pH, browning, absorbance and color tone, and analyzed by high-performance liquid chromatography (HPLC) to determine whether it is possible to utilize AN from DRP-JAV+lye and that from the DRP lye that had been disposed. (1) The DRP lye contained a relatively large amount of AN, the recovery ratio of which was 0.85%. (2) The pH of the 18% salt-MI buffer solution of the purified AN was 1.30 because of the added salt, and did no change until the 60 day. The pHs of the other sample solutions showed no change during the storage for 60 days. (3) The extent of browning increased with storage for each JAV sample when stored at 25°C for 60 days. (4) The relative absorbance, which was obtained by assigning 100 to E at λ_525nm before storage, of DRP-JAV+lye increased during storage. The relative absorbance of the other sample solutions decreased. (5) From the changes in the color tone of the sample solutions, it is judged that DRP-JAV+lye cannot be used, for pickling Japanese apricot. However, it is very much possible to utilize the purified AN extracted from DRP lye. (6) Cis-and trans-malonyl shisonins of DRP lye were hydrolyzed to cis-and trans-shisonins during storage. However, the color tone of the lye was significantly influenced by the increase in the extent of browning.

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Phenolic compounds were analyzed in the outer, middle and inner layers of the peel and in the pulp of bananas during ripening from the ripening-initiation. The major phenolic compound found was dopamine followed by 3, 4-dihydroxyphenylalanine (L-DOPA), tyramine and tyrosine in all portions of the bananas. These compounds located mainly in the outer layer of peel followed by the middle and inner layers of the peel and the pulp. The concentration of dopamine decreased during ripening in all portions of the fruit, particularly in the outer layer of the peel in which senescent spotting appeared at a late stage of storage. On the other hand, those of the other compounds, namely L-DOPA, tyrosine and tyramine increased during ripening. Polyphenol oxidase (PPO) activity was detected in all portions of the fruit ; however, it increased only in the outer layer of the peel. Short-term (24h) nitrogen-gas treatment of the ripening-initiated banana delayed the induction of senescent spotting and the decrease in dopamine content, while it increased the PPO activity of the nitrogen-gas-treated bananas to the same extent as that of air-treated bananas. These results indicate that dopamine is used as substrate of PPO for the formation of brown pigments of senescent spotting.

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In this study, we isolated viable cells from various meats and determined the characteristics and taxonomic position of the Pseudomonas strains isolated. As a result, the viable cell counts ranged from 10³ to 10⁶ cfu/g. In addition, all the meat samples contained strains belonging to the genus Pseudomonas. Most of the Pseudomonas isolates grew at 4°C and decomposed lipids and proteins; they were identified as Pseudomonas fluorescens. Recently, sanitation has become well based on HACCP and etc. However, the number of cells and bacterial species consisting one part of meat samples have not changed compared with those reported 20 years ago.

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