Processing and Storage Influences on the Chemical Composition and Quality of Apple, Pear, and Grape Juice Concentrates

Quantification of enzymatic browning kinetics in pear slices using non-homogenous ∗ color information from digital images

“…Table 1 shows that when the traditional method was applied (L * mean value), enzymatic browning rate parameters ranged between À0.007 and À0.002 min À1 for all cultivars, and PP cultivars showed the lower rate parameter; while AP and BP cultivars had no statistical differences in the rate parameters. The calculated values of the enzymatic browning rate parameters in this study could be different from other investigations since the degree to which pears turn brown depends not only of the cultivars but also of other factors such as the endogenous phenolic and polyphenol oxidase content among others (Amiot, Tacchini, Aubert, & Oleszekz, 1995); in fact, it has been demonstrated that pear phenolic composition varies greatly with cultivar, stage of maturity and postharvest storage conditions (Amiot, Tacchini, Aubert, & Nicolas, 1992;Oleszek, Amiot, & Aubert, 1994;Ranadive & Haard, 1971;Wrolstad et al, 1989). However, Amiot et al (1992) and Soliva-Fortuny, Alos-Saiz, Espachs-Barroso, and Martin-Belloso (2004) concluded that for pears picked at dates close to the commercial maturity stage, the susceptibility to browning was not greatly different.…”

Description of the kinetic enzymatic browning in banana (Musa cavendish) slices using non-uniform color information from digital images

“…The values of enzymatic browning rate parameters calculated in this study could be different from other studies since the degree to which bananas turn brown depends not only on the cultivars but also on other factors, such as the endogenous phenolic and polyphenol oxidase content, among others (Amiot, Tacchini, Aubert, & Oleszekz, 1995); In fact, it has been demonstrated that phenolic composition varies greatly with cultivar, stage of maturity and postharvest storage conditions (Amiot, Tacchini, Aubert, & Nicolas, 1992;Oleszek, Amiot, & Aubert, 1994;Ranadive & Haard, 1971;Wrolstad et al, 1988). However, Amiot et al (1992) and SolivaFortuny, Alos-Saiz, Espachs-Barroso, and Martin-Belloso (2004) Table 1 k (min À1 ) and n parameters (average) obtained for the browning fraction conversion data, for L à and b à channel colors.…”

The partial compositional characteristics of apple juice from 175 apple varieties

“…Various factors such as cultivar, growing region, climate, cultivar practices, harvest maturity (Drake and Eisele, 1997), storage atmosphere (Drake and Eisele, 1994), storage conditions (Drake et al, 2002;Drake and Eisele, 1999), shipping (Babsky et al, 1989) and processing (Spanos et al, 1990;Wrolstad et al, 1989) are known to affect the chemical composition of apple juice and apple juice concentrate. One of many objectives of these investigations was to define the parameters for the authenticity of apple juice based on such analysis as: Brix , titratable acidity, ash, pH, proline, specific gravity, formal index values, sugars, non-volatile organic acids, minerals, amino acids, phenolics, and isotopic carbon ratios (Lee and Wrolstad, 1988c) to produce individual, combined, or matrix databases (Elkins et al, 1988;Lee and Wrolstad, 1988b;Wallrauch, 1988;Evans et al, 1983).…”