Texture dynamics during postharvest cold storage ripening in apple (Malus×domestica Borkh.)

Analysis of the dynamic mechanical properties of apple tissue and relationships with the intracellular water status, gas distribution, histological properties and chemical composition

“…1) varied between about 1 and 5 Â 10 6 N m À2 , going from very soft to very firm apples (Table 1B). These results are slightly higher than those reported in a previous study on several cultivars sampled in similar cortex area as ours in which the modulus measured by force displacement on various cultivars ranged from 0.5 to 2 Â 10 6 N m À2 (Costa et al, 2012), although the minimum modulus was similar. In this study, EC had a significantly lower Young's modulus (Table 1B, statistics group a) than the other cultivars, and Ariane had the highest (Table 1B, statistics group c).…”

“…In this study, EC had a significantly lower Young's modulus (Table 1B, statistics group a) than the other cultivars, and Ariane had the highest (Table 1B, statistics group c). The Young's modulus and the storage modulus for all cultivars decreased with storage time as previously measured by Small Amplitude Oscillatory Shear on Granny Smith and Golden Delicious cultivars (Costa et al, 2012;Varela et al, 2007). Moreover, previous studies reported a decrease in firmness measured by sensory analysis (Gwanpua et al, 2014;Harker and Hallett, 1992;Johnston et al, 2002).…”

Dynamic volatile organic compound fingerprinting of apple fruit during processing

“…2), which have been mostly related with the consumer perception of firmness and crispiness, respectively (Costa et al, 2011). In accordance with Costa et al (2012), the textural behavior of the three apple cultivars differed during the ripening progression. The apple variety 'Golden Delicious' was characterized, indeed, by a rapid loss of firmness during ripening (almost 40%) together with a reduced acoustic response (around 60%), typical of a mealy fruit (Fig.…”

A candidate gene based approach validates Md-PG1 as the main responsible for a QTL impacting fruit texture in apple (Malus x domesticaBorkh)

“…The second category is defined by acoustic signatures, and is related to the cell wall breaking phenomenon with the consequent release of internal pressure [4,5]. Texture change is a physiological event which occurs naturally throughout fruit development and ripening [6], and the magnitude of texture decay is extremely variable between different apple varieties [7]. The variability observed is the result of physiological mechanisms activated during the fruit maturation and ripening, in which a large number of enzymes are co-ordinately expressed to remodel the cell wall/middle lamella polysaccharide structure, and regulated, amongst other factors, by the effect of ethylene and transcription factors [8,9].…”

“…The variability observed is the result of physiological mechanisms activated during the fruit maturation and ripening, in which a large number of enzymes are co-ordinately expressed to remodel the cell wall/middle lamella polysaccharide structure, and regulated, amongst other factors, by the effect of ethylene and transcription factors [8,9]. The remodelling process is associated with a decrease in cell-to-cell adhesion, resulting in the separation of cells along the middle lamella (mealy texture) rather than a primary cell wall breaking (crispy texture; [1,7]) when the fruit is consumed. Fruit softening and textural changes thus involve a coordinated modification of the primary cell wall and middle lamella polysaccharide structure, a process which initially takes place with a dissolution of the pectin polysaccharides of the middle lamella, followed by a disruption of the ordered structure of the primary cell wall [10,11].…”