Chemical and sensory variability in table grapes

Abstract

This study is concerned directly with the first two factors only, although textural changes associated with the ma turity level of the fruit could possibly influence over-all sensory impressions. Flavor is defined as the complex reac tion of taste and olfactory receptors; the olfactory aspect is believed to be secondary with non-muscat varieties. In this study, only the taste aspect of flavor will be considered.There are four possible tastes in grapes: acidness (tart, or sour), sweet ness, saltiness, and bitterness. White grapes are very low in tannins and other bitter-tasting substances. Red grapes have more bitter-tasting substances, but these are mainly in the skins and unless skins are vigorously chewed little bitter taste is experienced. Grapes have very little salty taste, though tartrates give a reaction. Tartrates as buffer agents re pressing the ionization of malic and tartaric acids may, however, influence the acid taste.The characteristic gustatory sensation of grapes is their sweet-sour taste. The main sugars found in grapes, levulose and dextrose, are of very unequal sweet ness (about 1.5:1) and presumably the

Understanding American and Chinese consumer acceptance of ‘Redglobe’ table grapes

“…American consumers chose the 'neither like nor dislike' option only a few times (average 7%), whereas Chinese consumers chose it frequently (average 34%). Our data confirmed that 'Redglobe' consumer acceptance is more sensitive to SSC:TA ratio than SSC alone as has been reported for 'Perlette' and 'Thompson Seedless' grown in California and Israel (Nelson et al, 1963(Nelson et al, , 1972(Nelson et al, , 1973Guelf-Reich and Safran, 1971). However, the relationship between consumer acceptance and SSC:TA ratio is highly related to consumer acceptance within a TA or SSC range.…”

“…The relationship between consumer preference and fruit chemical composition has been studied in different commodities. Several researchers have established that consumer preference is well related with fruit soluble solids concentration (SSC), titratable acidity (TA) and SSC:TA ratio in kiwifruit (Gorini and Lasorella, 1990;Crisosto and Crisosto, 2001); peaches (Parker et al, 1991); cherries (Kappel et al, 1996;Drake and Fellman, 1987); grapes (Rodan, 1988;Nelson et al, 1963Nelson et al, , 1972Nelson et al, , 1973Guelf-Reich and Safran 1971); and oranges (Pehrson and Ivans, 1988). Recently, it has been reported in mango that sugars and acid enhance human perception of specific flavor notes, including aromatics (Malundo et al, 2001).…”

Study of the effect of ripening stages and climatic conditions on the physicochemical and sensorial parameters of two varieties of Vitis vinifera L. by principal component analysis: influence on enzymatic browning

“…Aroma was also correlated with SSC in Mystery and Prime grapes 41. Both SSC and TA have been shown to be very significant factors in the palatability of table grapes 42. Winkler43 demonstrated that the SSC/TA ratio is a better index of the palatability of table grapes than SSC alone.…”

Evaluación del nivel de aceptabilidad para las variedades Italia, Napoleón y Redglobe en el mercado español

“…Uno de los primeros trabajos que tuvo como enfoque central el estudio sensorial de la uva de mesa fue el realizado por Nelson et al (1963), que trabajaron con las variedades Perlette, Cardinal, Thompson Seedless, Ribier y Tokay y analizaron 1 aspectos sensoriales relacionados al color y flavor, y su efecto sobre la preferencia y aceptación por el consumidor.…”