Persimmon fruit

De Ancos, B., Gonzalez, E., and Cano, M.P., Effect of high-pressure treatment on the carotenoid composition and the radical scavenging activity of persimmon fruit purees, J. Agric. Food Chem., 48, 3542, 2000. 

Persimmon fruit slices stored under air showed a decrease in carotene content (Wright and Kader 1997a). The air + 12% carbon dioxide treatment resulted in a loss of cryptoxanthin over the first 3 days, followed by a slight recovery. Levels of carotene... 

Three PAG-active compounds were identified from the extracts of pheromone glands of the persimmon fruit moth, Stathmopoda masinissa Meyrick (Lepidoptera Oecophoridae). These were AE,6Z)-4,6-hexadecadienal and the corresponding acetate (EA,Z6- 6 OAc) and alcohol EA,Z6- 6 OY ). A preliminary field trail confirmed that the acetate as a single component attracted male moths, the possible roles of the aldehydes and the alcohol as components of lures remains to be determined. 

Tanaka, T. et al., Chemical evidence for the de-astringency (insolubilisation of tannins) of persimmon fruit. J. Chem. Soc. Perkin Trans. /3013, 1994. 

Matsuo, T. and Itoo, S., A model experiment for de-astringency of persimmon fruit with high carbon dioxide treatment in vitro gelation of kaki-tannin by reacting with acetaldehyde. Agric. Biol Chem. 46, 683, 1982. 

Imaging has also been applied to the study of chilling injury in persimmon fruit,312 to the study of growth and ripening of kiwi fruit,313 and to the detection of pitted olives, while a conveyer belt transports the fruits through a low-field NMR magnet.314... 

C) Creation of anaerobic conditions by enclosing the fruits in polyethylene (PE) bags under vacuum. In PE bags containing six persimmon fruits/bag, the O2 level remained low (3%) for several weeks while the CO2 level reached 30% after 2 days at 20 °C, in addition to the accumulated AA and ethanol (Pesis et al. 1986). It is possible to flush N2 or CO2 through the PE bags that had been vacuum-treated, in order to create various atmospheric conditions (Pesis et al. 1988). 

Matsuo T, Ito S (1977) On mechanisms of removing aastringency in persimmon fruits by carbon dioxide treatment I. Some properties of the two processes in the deastringency. Plant Cell Physiol 18 17-25... 

Sugiura A, Harada H, Tomana T (1975) Studies on the removability of astringency in Japanese persimmon fruits I. On tree removal of astringency by ethanol treatment (Part I). J Jpn Soc Hortic Sci 44 265-272... 

The strongly astringent taste of persimmon fruits arises from soluble tannins that accumulate in large specialized cells called tannin cells. In this chapter, some chemical properties of persimmon tannins, an outline of simple and reliable methods for estimation of the degree of astringency and the amount of tannins, and some aspects of the physiological changes in the tannin contents of persimmon fruits will be described. 

Persimmon tannin in soluble form reacts with ferric chloride, forming tannin-Fe ion complexes, which are blue-black. We can estimate the degree of astringency in persimmon fruits by colour development during the reaction. 

Seasonal changes in fruit diameter, colour development of the peel (estimated from colour charts) and soluble tannins of persimmon fruits of the cultivars Hiratanenashi (PVA, a parthenocarpic type Fig. 7A) and Jiro (PCNA Fig. 7B) were studied ca.every 10 days at Tsuruoka City in the north of Japan. Soluble tannins in the fruit flesh were measured by the Folin-Denis method. In Tsuruoka, both cultivars usually bloom, starting early in June. 

As mentioned before, the amount of soluble tannin that causes astringency in persimmon fruits is usually estimated visually by the tannin print method and can be measured quantitatively by the Folin-Denis method. There is also a protein precipitation method for the measurement of soluble tannins (Hagerman and Butler 1978). In that method, the soluble tannin content is assayed by the addition of the sample to a standard solution of protein and the isolation of insoluble tannin-protein complexes. The complexes are dissolved in alkaline solution, to which ferric chloride is added. The absorbance of the solution at 510 nm is measured. 

Eaks IL (1967) Ripening and astringency removal in persimmon fruits. Proc Am Soc Hortic Sci 91 868-875... 

Kato K (1984) The condition of tannin and sugar extraction, the relation of tannin concentration to astringency and the behaviour of ethanol during the de-astringency by ethanol in persimmon fruits. J Jpn Soc Hortic Sci 53 127-134 (in Japanese with English Summary)... 

Matsuo T, Ito S (1977b) Kaki tannin. J Chem Biol (Kagaku to Seibutsu) 15 732-736 (in Japanese) Matsuo T, Ito S (1978) The chemical structure of kaki-tannin from immature firuit of the persimmon Diospyros kaki L.). Agric Biol Chem 42 1637-1643 Nakabayashi T (1971) Studies on tannins of fhiits and vegetables. VII. Difference of the components of tannin between the astringent and non-astringent persimmon fruits. J Jpn Soc Food Sci Technol 18 33-37... 

Inkyu, K., Juseop, K., and Jaekyun, B. (1996). The role of P-galactosidase on the modification of cell-wall components in persimmon fruit. Journal of the Korean Society for Horticultural Science 31, 528-533. 

Fukami M, Hattori Z, Okonoyi T 1978 Detoxifying effects of persimmon fruit tannin on snake venom and bacterial toxins. Sankyo Kenkyusho Nempo 30 104-111... 

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