Quality of `Buerre Bosc' and `Doyenne du Comice' pears in relation to harvest date and storage period
H. John Elgar, Christopher B. Watkins, Shona H. Murray and F. Anne Gunson
Postharvest Biology and Technology. Vol., 10 Issue 1. Jan 1997. pp. 29-37.
1997
บทคัดย่อ
Fruit from two winter pear cultivars, `Buerre Bosc' and `Doyenne du Comice', were harvested during maturation at weekly intervals during two seasons. Ripening behaviour during 1 week at 20°C was assessed at harvest and after 2, 4, 6, 8, 12, 16 and 20 weeks of storage at -0.5°C. During ripening, the two cultivars showed distinctly different patterns of ethylene production after chilling. Ethylene production of `Buerre Bosc' fruit followed typical climacteric patterns and generally exhibited progressively higher rates with longer storage. That of `Doyenne du Comice' fruit increased with longer storage when initially transferred to higher temperature, but tended to decline during the ripening period. Ripening of fruit of both cultivars, as judged by physical measurements, was affected by harvest date and storage period. Early-harvested fruit required longer periods of storage before reaching full ripeness than late-harvested fruit (6 weeks cf. 2 weeks). Fruit still retained the ability to ripen fully after 20 weeks of storage. The extractable juice contents and titratable acidity concentrations of ripened fruit decreased with increasing storage, but these changes were less pronounced and occurred later than those for flesh firmness and background colour. Sensory analyses indicated that harvest date only affected eating quality of `Doyenne du Comice' fruit. Fruit stored for 4-8 weeks generally had the highest flavour intensity, juiciness and overall quality. These results indicate that `Buerre Bosc' fruit should be stored for a minimum of 4 weeks depending on harvest date, and best quality is obtained between 4 and 12 weeks after harvest. In contrast, optimum quality of `Doyenne du Comice' fruit occurred between 8 and 20 weeks after harvest.