Radiation Processing of Foods, Some Effects of Gamma Radiation on Keeping Quality of Apples

Abstract

Storage studies of applies treated with gamma radiation were conducted. The principal immediate effect was a softening by radiation dosages in excess of 10 kilorads, and a transient stimulation of respiratory oxygen consumption. Sauce was prepared from treated apples and evaluated as to quality. The principal effect of irradiation was a loss of "grain," which resulted in no significant change in acceptability or preference of the product. In storage, irradiated fruit softened at a much slower rate than did nonirradiated fruit. Despite the initial softening, the combined effect was fruit firmer than normal. Softening was positively correlated with changes in pectin content. Irradiation produced a marked reduction in the incidence of storage scald, and evidence of reduction in true brown core was suggested. Some slight indication of induced injury to the skin of one picking of one variety was found, and some impairment of flavor was described at high dosages in another variety.

Comparative Study on the Sensory Properties of Fuji Apples and Niitaka Pears Irradiated by Gamma Rays, Electron Beams, or X-rays

“…As irradiation dose and storage time increase, firmness decreases. Numerous studies have reported that the softening of fruits induced by irradiation is associated with the decrease in total pectin content (Gunes et al, 2001;Massey and Smock, 1964). Gamma ray irradiation at doses above 400 Gy decreases the firmness of Fuji apples immediately after irradiation (Al-Bachir, 1999; Gunes et al, 2001;Mostafavi et al, 2012).…”

Effects of irradiation on respiration and ethylene production of apple slices

“…Irradiation resulted in stimulation of respiration rate of apples, and generally tissues from more mature fruit were less sensitive to irradiation 8. 9 Romani et al 10 observed a divergent respiratory response of ‘Bartlett’ pears to irradiation dose, with higher levels of irradiation (6–10 kGy) resulting in a reduced respiratory activity compared with that of control fruits or those irradiated at lower levels (2–2.5 kGy).…”

Studies on enhancing the keeping quality of peach (Prunus persica Bausch) Cv. Elberta by gamma-irradiation

“…The conversion of WSP fractions to water-insoluble pectic acids during the onset of senescence results in decrease in WSP fractions. The low dose irradiation and low temperature storage have markedly delayed the activity of protopectinase and pectin methyl esterase enzymes responsible for degradation of protopectin and pectin (Massey et al, 1964). Loss in weight increased in all treatments including control during storage and the increase was significantly less under refrigerated conditions.…”

“…Irradiation and refrigeration are known to have a delaying effect on respiration and senescence, hence resulting in higher retention of TSS during storage. Irradiation at high doses lead to altered pore permeability, favouring respiration and senescence and thereby causing depletion in TSS (Massey et al, 1964;Wills et al, 1996;Chetan et al, 2006).…”