| Summary: | 碩士 === 國立屏東科技大學 === 農園生產系所 === 96 === Postharvest physiology of ‘TN11’、‘TN17’ and ‘TN18’ pineapple (Ananas comosus (L.) Merr.) fruit collected from Wu’s orchard, Ma-Chia, Pingtung county, were studied. A series of studies including postharvest physiology, packaging with polyenhtlene (PE) bag, chemical treatments, various maturity, temperature and fruit components were conducted.
The result showed that respiration and ethylene of three pineapple cultivar increased with storage temperature. The pineapple fruit exhibited typical non-climacteric fruit identified by no climacteric respiratory and ethylene peak.
The ‘TN18’ fruit packaged with sealed PE bag containing ethylene absorbents at 15℃, extended storage life (about 31.7 days) significantly. No significant difference on storage life of packaged and unpackaged ‘TN11’ and ‘TN17’ fruit. The storage life of ‘TN17’ and ‘TN18’ fruit soaked with 25％ ClO2 for 1 minute were 36.0 and 33.7 days and significantly different from control. However, there is no significant effect on storage life of ‘TN11’ fruit soaked with ClO2. Total soluble solids (TSS), titratable acidity (TA), sugar/acid ratio and peel hue angle (θ) of pineapple fruits were decreased with storage. Vitamin C levels at harvest and storeage of ‘TN18’ were significantly higher than the other two pineapple cultivar. Besides, pH value, moisture content of pulp, lightness and chroma of peel were increased with storage time. All cultivar tested showed fruit harvested at 1/4-yellow shell color stage had best storage life at 15℃(about 36.7, 34.0 and 29.0 days, respectively for ‘TN11’, ‘TN17’ and ‘TN18’). No significant difference on quality in storage between fruit harvested at half-yellow and 3/4-yellow shell color stage. Maturity at 1/4-yellow shell color stage and 15℃ in storage were suggested to extend storage life and quality in transportation of pineapple fruits.
Among the three pineapple cultivar studied, ‘TN17’ was most susceptible to chilling injury (blackheart) and followed by ‘TN18’ and ‘TN11’. Both ‘TN17’ and ‘TN18’ cultivar expressed blackheart symptoms at 25℃ when stored beyond 9 days at 15℃. The susceptibility of pineapple fruit to chilling injury increased with maturity.
There was variation of flavor among pineapple fruit parts. The TSS, sugar/acid ratio and pH value increased from crown end to basal tissue and TA levels showed inverse trend. After harvest, the sucrose content was the highest (9.104 g/100g) and flowed by fructose (3.480 g/100g) and glucose (2.634 g/100g). Maltose was not detected.
|
|---|
