ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

Fruit development, harvest index and ripening changes of guavas produced in central Mexico

Edmundo Mercado-Silva, Pedro Benito-Bautista and Ma. de los Angeles Garc?a-Velasco

Postharvest Biology and Technology Vol: 13 Issue: 2 Pages: 143-150

1998

บทคัดย่อ

The variabilities in guava (Psidium guajava cv. `Media China') development period, and physical and chemical properties were determined for the spring_¯summer and autumn_¯winter harvest seasons in Mexico. At 20 day intervals, fruit diameter, weight, specific gravity (SG), total soluble solids content (SSC), ascorbic acid, titratable acidity, color and firmness were determined. Fruit growth showed a double sigmoidal pattern, with spring_¯summer fruit needing 130 days while autumn_¯winter fruit required 190 days to reach the ripe stage. Acidity decreased during development while ascorbic acid and SSC increased during the last stage of growth. Autumn_¯winter fruit had higher SCC, titratable acidity, and ascorbic acid concentrations than spring_¯summer fruit. The climacteric peaks in carbon dioxide and ethylene production were reached after 7_¯8 days in autumn_¯winter fruit as compared with 4_¯5 days in spring_¯summer fruit. The best maturity index was color: the mature green fruit could be harvested with L*, a* and Hue values of 65±3, -15±2 and 110±2, respectively. These values corresponded to fruit with yellowish green external color.