The response of unripe Conference pears to modified atmosphere retail packaging

Abstract

Unripe green Conference pears with initial firmness values of 46-55N were sealed in modified atmosphere (MA) low density polyethylene (LDPE, 30 p) pillow packs and in perforated control packs on three dates during [1985][1986]. Changes in pack atmosphere composition, skin chlorophyll content, flesh firmness and sensory quality were monitored during 14-20 days simulated shelf-life at 20°C. In MA packs, equilibrated atmospheres containing 5-9% C02 and <5% 0 2 developed within c. 3 days. Chlorophyll degradation was completely inhibited by MA and resumed when packs were perforated, but MA only partially retarded the rate of flesh softening. Variations in the rate of ripening changes in duplicate MA packs could not be explained simply by differences in pack atmospheres. Furthermore, pears retarded by MA packaging failed to develop the normal sweet, aromatic flavour and succulent, juicy texture of 'eating-ripe' fruit, even when the packs were perforated after 4 days.The differences in the responses of pears and apples to MA packaging, and the limitations of using this technique for the commercial marketing of English pears are discussed.

Limitations to modified atmosphere packaging for extending the shelf‐life of partly ripened Doyenné du Comice pears

“…These results show that MA packaging retarded the rates of degreening and softening of conditioned, part-ripe Comice in much the same way as had been reported for unripe Conference (Geeson et al, 1991) and Comice pears. However, because the skin colour had already progressed to an acceptable stage of yellow before packing, the slight retardation in the rate of softening (Tables 3 and 4) in the one m-p MA packs appeared to offer a better opportunity for extending ambient shelf-life by several days without adversely affecting their eating quality, providing that the pears were not too soft when packed.…”

“…Previous work (Geeson et al, 1991) showed that, when unripe Conference pears (eight-fruit units) were held at 20°C in 30 p low density polyethylene (LDPE) modified atmosphere (MA) packs in which the atmosphere equilibrated to 5-9% C 0 2 and 2-5% 02, chlorophyll degradation was inhibited but flesh softening was only partly retarded. Moreover, pears held in MA packs failed to develop the normal sweet aromatic flavour and juicy, melting texture of normal 'eating-ripe' fruit, even when the packs were perforated to allow ingress of air after only 4 days at 20°C.…”

Quality of Modified Atmosphere Packaged “Bartlett” Pears as Influenced by Time and Type of Storage

“…Other researchers (Smith et al. 1989; Geeson et al. 1991a,b) indicated similar color changes with pears from MAP.…”

“…The influence of MAP on quality of fruit with a naturally longer shelf life is variable. Some investigators report benefits on quality (firmness retention, reduced physiological disorders) in fruits with extended shelf life (Hewett and Thompson 1988; Geeson et al. 1991a; Zoffoli et al.…”

“…The influence of MAP on quality of fruit with a naturally longer shelf life is variable. Some investigators report benefits on quality (firmness retention, reduced physiological disorders) in fruits with extended shelf life (Hewett and Thompson 1988;Geeson et al 1991a;Zoffoli et al 2002). Other researchers (Smith et al 1989;Geeson et al 1991b) indicate that problems can occur with the use of MAP and fruit, particularly injury in "Comice" and "Conference" pears.…”