Changes in the Physico-Chemical Properties of Persimmon (<i>Diospyros kaki </i>Thunb.) During Drying and Quality Deterioration During Storage

Abstract

Dried persimmon (Diospyros kaki Thunb.) is one of the most popular fruit products in East Asia, but its properties and consumer acceptance strongly depend on the drying process and storage conditions that are used. The quality of dried persimmon depends on its physical (color, texture) and chemical (tannin levels, sugar content, the presence of white powder on the surface) properties, which are drastically affected by the decrease in moisture content and composition changes that occur during the drying process and storage. Therefore, in the present report, the changes in the physico-chemical properties of dried persimmon that occur during the drying process and its quality degradation during storage are reviewed for providing fundamental information on the production of high-quality dried persimmon and storage management.

Natural Drying of Astringent and Non-Astringent Persimmon “Rojo Brillante”. Drying Kinetics and Physico-Chemical Properties

“…The ST values were similar to those of the non-astringent fruit. Tannin insolubilization during the drying process could be associated with structural flesh changes ( Figure 2 ), which happens during natural persimmon fruit ripening [ 2 , 32 , 38 ]. In astringent cultivars, the ripening process is accompanied by gradual tannin insolubilization, which leads to a progressive decline in ST with subsequent astringency reduction [ 3 ].…”

“…These differences were still found after 81 days (Figure 3c). The color changes that occurred during the drying period were the result of several biochemical reactions, such as degradation of carotenoids, decomposition of other color pigments, and enzymatic and non-enzymatic reactions [32]. Yamada et al (2009) [33] suggested that the oxidative and non-oxidative degradation of ascorbic acid would contribute markedly to the browning of this product type, while enzymatic browning, by polyphenol oxidase, and the Maillard reaction, between amino acids and reducing sugars would not play a key role.…”

Reformulation of Persimmon Value-Added Model: Product Downstream Development Strategy for Farmers in East Java, Indonesia

“…Persimmon fruit can be found in several regions on the islands of Java and Sumatra, but fruit grown in the East Java region is of better quality and produced in greater quantity than other regions, especially in the Bumiaji, Ampelgading, and Tirtoyudo regions [23]. Farmers usually soak persimmons in a lime solution or use alcohol, carbon dioxide, and hot water to produce a higher-quality taste [24,25]. This is because persimmons have an astringent taste [26].…”

Tratamientos de secado para la obtención de ingredientes de alto valor nutritivo a partir del destrío postcosecha de caqui

“…These differences were still found after 81 days (Figure 3c). The color changes that occurred during the drying period were the result of several biochemical reactions, such as degradation of carotenoids, decomposition of other color pigments, and enzymatic and non-enzymatic reactions (Jia et al, 2019). Yamada et al, (2009) suggested that the oxidative and non-oxidative degradation of ascorbic acid would contribute markedly to the browning of this product type, while enzymatic browning, by polyphenol oxidase, and the Maillard reaction, between amino acids and reducing sugars would not play a key role.…”

“…Tannin insolubilization during the drying process could be associated with structural flesh changes (Figure 2), which happens during natural persimmon fruit ripening (Asgar et al, 2004;Jia et al, 2019;. In astringent cultivars, the ripening process is accompanied by gradual tannin insolubilization, which leads to a progressive decline in ST with subsequent astringency reduction .…”