Delays to cool affect visual quality, firmness and gloss of bell peppers and eggplants
M. Cantwell and A. Thangaiah
Perishables Handling Quarterly. Issue No. 107, August 2001, Pages 17-20.
2001
บทคัดย่อ
Temperature management is key to marketing high quality produce, and it is generally recommended to “cool as soon as possible”. Specific data is lacking for many fresh products. We evaluated the impact of water loss and delays to cool on quality attributes (visual appeatance, gloss, weght loss color change, decay development, and firmness) of stored mature-green bell peppers and Japanese eggplants. Objective measurements o gloss and firmness were highly correlated with subjective scores of both attributes. A weight loss of 2 to 4% reduced bell pepper firmness, gloss and visual quality. Average weight loss with cooling delays at 37 0C (35-38% RH) and 25 0C (48-50% RH) was 0.13 and 0.06% per hour, respectively. Significant decreases in gloss values occurred with cooling delays of 9 hours at both temperatures. Important decreases in firmness occurred after a 9 hour delay at 37 0C, but until after an 18 hour delay at 25 0C. No color change occurred in the peppers held at 25 0C for up to 18 hours, but after 12 hours at 37 0C, some peppers began to color. Delays to cool should be less than 9 hours at 20-25 0C and less than 6 hours at 37 0C for mature-green bell peppers. For Japanese eggplants, visual quality scores were significantly decreased with a 3% weight loss, but differences in firmness were measurable with 2% weight loss. Gloss values were not significantly affected until weight loss exceeded 8%. Firmness and gloss were not affected as rapidly as the overall visual quality score by delays to cool. Firmness values decreased significantly after 9 and 12 hours at 37 0C and 25 0C, respectively. Gloss values decreased significantly after delays of 9 hours at either temperature. For Japanese eggplants, delays to cool should be less than 6 hours at 20-25 0C and less than 3 hours at 37 0C.