Compositional Variation in Sugars and Organic Acids at Different Maturity Stages in Selected Small Fruits from Pakistan

Abstract

Selected soluble sugars and organic acids were analyzed in strawberry, sweet cherry, and mulberry fruits at different ripening stages by HPLC. The amounts of fructose, glucose and sucrose were found to be: strawberry (1.79–2.86, 1.79–2.25 and 0.01–0.25 g/100 g FW), sweet cherry (0.76–2.35, 0.22–3.39 and 0.03–0.13 g/100 g) and mulberry (3.07–9.41, 1.53–4.95 and 0.01–0.25 g/100 g) at un-ripened to fully-ripened stages, respectively. The strawberry, sweet cherry and mulberry mainly contained tartaric, citric and ascorbic acids in the range of 16–55, 70–1934 and 11–132 mg/100 g; 2–8, 2–10 and 10–17 mg/100 g; 2–118, 139–987 and 2–305 mg/100 g at un-ripened to fully-ripened stages, respectively. Fructose and glucose were established to be the major sugars in all the tested fruit while citric and ascorbic acid were the predominant organic acids in strawberry and mulberry while tartaric acid was mainly present in sweet cherry. The tested fruits mostly showed an increase in the concentration of sugars and organic acids with ripening.

Chemical Composition, Nutritional Properties and Antioxidant Activity of Monkey Apple (<i>Anisophyllea laurina </i><i>R</i><i>.</i><i> </i><i>Br. ex Sabine</i>)

“…In this study, the values of citric acid content in pulp was higher than in pine apple (2.2 g/kg), in orange(4.5 g/kg), in grape (13.1 g/kg) and in lime (41.2 g/kg) as reported by [27] and in mulberry species (M. laevigataand M. nigra 773-987 mg/100 g) as reported by [28] Organic acid contents in monkey apple were higher than that of pomegranate (Punica granatum L.) : oxalic acid (0.0313 to 1.0167 g/L), malic acid (0.1175 to 2.2302 g/ L), citric acid (0.6130 to 2.1823 g/ L), fumaric acid ( 0.0119 to 0.2990 mg/ L) and tartaric acid (0.0330 to 0.1266 g/ L) values as reported by [29].…”

Changes in the levels of selected organic acids and sugars in apple juice after cold storage

“…Most perishable commodities, however, are stored under refrigerated conditions, and storage life may range from eight to ten days for highly perishable fruits like berries to eight to ten weeks for less-perishable commodities like squash, pumpkin, apples, grapes and pears (Barrett 2007). Soluble sugars in fruits are mainly represented by sucrose, fructose and glucose, whilst malic, citric, and tartaric acids are the primary organic acids (Mahmood et al 2012). The right proportion of these sugars determines the quality of the fruits.…”

Evaluation of healthy and sensory indexes of sweetened beverages using an electronic tongue

“…(i) The sweetness perception (SWP) index of each beverage, an estimate of total human sweetness perception, was calculated as sucrose equivalent based on the amount and relative sweetness (RS) of each individual sugar (RS Sucrose = 1.00; RS Glucose = 0.74; RS Fructose = 1.73) [13][14][15]:…”

“…In fact, these indexes can be more useful nutritional concepts than the chemical classification of carbohydrates, since they may allow a better understanding of the relation between physiologic effects of carbohydrate-rich foods and health [10]. Among the sensory indexes the following are used as consumer's beverage acceptability or overall taste indicator: the total acid flavor, the sweetness index concept, used to assess fruit beverage sweetness as sucrose equivalent [13][14][15] and the wellbalanced flavor index, evaluated from the ratio between total sugars and total acids contents [2][3][4].…”

“…These indexes are influenced by the nature and source of carbohydrates and organic acids present in beverages and may be calculated from their contents, usually obtained experimentally by liquid chromatography based techniques [15][16][17][18]. These approaches, although accurate, are time-consuming, expensive, require qualified technical human resources and, usually, are not ambient friendly.…”