Physicochemical changes in cubiu fruits (Solanum sessiliflorum Dunal) at different ripening stages

Abstract

Cubiu shrubs (Solanum sessiliflorum Dunal) have drawn the attention of researchers for their biological versatility (preferential heliophilous or facultative ombrophilous shrubs), their capacity to grow in upland or lowland areas, and the good technological quality of their fruits for the food industry. The aim of this study was to verify physicochemical changes in cubiu fruits during maturation. The fruits were harvested from the experimental station of olericulture of the Instituto Nacional de Pesquisas da Amazônia (INPA), Brazil. The analyses were performed in whole cubiu fruits (peel, pulp, and placenta) at four traditional ripening stages (green, turning, ripe, and fully ripe) for the determination of weight, moisture, total solids, total carotenoids, proteins, lipids, and ash. Cubiu fruits showed large weight variation, with amodal distribution. The ripe stage was critical to maintain moisture, and from that stage on, water loss became evident. The lipids increased steadily over the four ripening stages, maintaining, however, insignificant calorie content. Total carotenoids, proteins, and ash reached the maximum level at the fully ripe stage. With the exception of weight and moisture, all physicochemical changes exhibited the same general behavior, i.e. they increased as the fruits ripened at the four investigated stages.

Biochemical Changes of Cubiu Fruits (<i>Solanum sessiliflorum</i> Dunal, Solanaceae) According to Different Tissue Portions and Ripening Stages

“…Thus, the pulp and the placenta are more protected from this vast exposure to the environment, saving the internal moisture of the fruit. However, moisture loss is an initial trigger for ripening; on the other hand, the greater retardation in moisture loss will increase the potential for extending storage life [1]. It is worth emphasizing the dietetic importance of the high percentage of moisture of cubiu fruits in all tissue portions and ripening stages investigated herein.…”

“…According to methodology previously described [1], freshly harvested cubiu fruits were homogenized in the blender and immediately kept in a furnace at 65˚C until constant weight was reached (12 hours). The dry matter was estimated by difference.…”

“…hydrosoluble flavonoids); the washed hexane solution (with carotenoids) being dried and its absorbance being read at 450 nm on the spectrophotometer (acetone (5 mL) and hexane (45 mL) as blank in the same solvent volume) [1].…”

“…In contrast to vitamin A and its potential toxicity (or hypervitaminosis A), carotenoids are not toxic even when ingested in large amounts (e.g. in anorexia nervosa and/or bulimia nervosa) due to their low intestinal absorption, but when the latter increases, the liposoluble pigments are deposited in the subcutaneous tissue, and the skin becomes yellow (hypercarotenosis or carotenodermia), a condition that usually resolves spontaneously [1] [24].…”

“…It can both inhibit polyphenol oxidase (as a chelating agent) and promote browning (in the presence of amino acids) [20]. Apart from these potential detrimental effects on fruit appearance, ascorbic acid is highly beneficial for Also, the amount of moisture is one of the most fundamental analytical procedures that can be performed on a food product; the dry matter that remains after moisture removal being commonly referred to as total solids [1]. TSS are especially used as indicators of total sugar content in fruits, providing information on the fruit maturation state; on the other hand, they are formed by water-soluble compounds such as organic acids, ascorbic acid and pectin [27] [28].…”