Improving Marketable Quality of Tomato: a Simulation of Shipping Conditions in Ghana

摘要

Aim: The study assessed the influence of a sequence of anticipated hazard elements (impact, compression, vibration) and shipment conditions on marketable quality under varying temperatures and ripeness stages. Study Design: The vibration test simulates a truck operating at highway speed and determines the ability of shipping units to withstand vertical and compression forces resulting from stacking during transport. Storage at 30oC depicted ambient conditions; 15 and 20oC are optimum temperatures for ripening; and pink and light-red ripeness depict typical harvest maturity in Ghana. Place and Duration of Study: The study was conducted at the Postharvest Science Laboratory of the Horticultural Sciences Department of the University of Florida from September to December 2011. Methodology: Round-type tomato at pink and light-red ripeness were subjected to a vibration test and incubated in ripening chambers set at 15, 20 and 30oC. Critical data was taken on days to red-ripe, CO₂, ethylene production, color, firmness, weight loss, pH, titratable acidity and soluble solids content. Results: Overall, the influence of vibration and ripeness on marketable shelf life was marginal; however temperature significantly (P≤0.05) influenced shelf life. Vibration increased weight loss, respiration and ethylene production, which were plummeted at lower temperature. Days to red-ripe indicated that tomato should preferably be marketed by 2-4, 8-12 and 10-15 days at 30, 20 and 15oC respectively, at pink to light-red ripeness under current distribution conditions. Best chemical properties were maintained at 15 and 20oC; vibration and ripeness did not influence chemical properties, but increasing temperature affected all physico-chemical properties. Conclusion: The study concludes that despite the cumbersome shipping conditions, tomatoes could be marketed at premium quality if lower storage temperatures were accessible. These facilities are beyond the purchasing power of small-holder traders, thus the involvement of the State and/or Private Sector to providing these facilities would be beneficial; particularly in urban markets where retail prices will merit such investments.