Thermal and Calcium Pretreatment Affects Texture, Pectinesterase and Pectic Substances of Frozen Sweet Cherries

Abstract

Freezing causes loss of turgidity and firmness in sweet cherries. Thermal pretreatment at 50°C for 10 min followed by immersion in 100 mM CaCl2 and thermal pretreatment at 70°C/2 min with or without immersion in 100 mM CaCl2 prevented freezing‐induced loss of firmness. Thermal pretreatments increased the pectin fraction soluble in EDTA, reduced the degree of pectin esterification, and increased both the concentration of divalent cations in the cell wall and the pectinesterase activity bounded to the cell wall. Immersion in CaCl2 increased the concentration of Ca2+ cations in the cell wall and enhanced the effect of thermal pretreatments on pectinesterase activity.

Effect of calcium additives on physicochemical aspects of cell wall pectin and sensory attributes of canned peach (Prunus persica (L) Batsch cv Andross)

“…7,9 Moreover, calcium ions have been proved to inhibit tissue weakening of processed fruit and vegetables. 4,8,41 Sensory and quality attributes were evaluated in order to take advantage of the benefits that calcium additives offer regarding physicochemical parameters of the cell wall framework and tissue retention.…”

Effect of temperature and pressure on the activity of purified tomato polygalacturonase in the presence of pectins with different patterns of methyl esterification

“…However, the food industry can benefit from a controlled activation of PME, while PG is selectively inactivated by choosing proper combinations of pressure and temperature. Consequently, the texture and juice viscosity of tomato-based products will be improved, as the partly deesterified pectin chains, formed after reaction with PME, may crosslink in the presence of divalent cations and are less susceptible to h-elimination chain breaking reactions during thermal processing (Alonso, Canet, & Rodriguez, 1997;Hoogzand & Doesburg, 1961;Hsu, Deshpande, & Desrosier, 1965;Stanley, Bourne, Stone, & Wismer, 1995;Steinbuch, 1976;Stolle-Smits, Beekhuizen, Recourt, Voragen, & van Dijk, 2000;Van Buren, 1979;Van Buren & Pitifer, 1992). Former enzyme inactivation studies, i.e.…”

Frozen green beans (Phaseolus vulgaris, L.) quality profile evaluation during home storage

“…This mostly affects colour, texture and flavour. Texture losses occur by softening processes, which are related to the hydrolisis of structural sugars, such as the decrease in pectin content (Alonso, Canet, & Rodrigez, 1997;Fuchigami, Hyakumoto, & MiYazaki, 1995) and the downshift in weight of hemicelluloses (Jackman & Stanley, 1995) by acid catalysed hydrolysis.…”