Background and methodology
The quality of tomatoes produced using conventional practices was compared with those grown organically. Fruit was harvested in December 2003 and January 2005 at the breaker stage and ripened at 20° C. When fruit were determined to be fully ripe by visual inspection, samples were collected for quality analyses (color, firmness, total soluble solids, pH, and total acidity). Sensory evaluation (duo-trio test with balanced reference) was conducted to determine whether consumers could perceive a difference between tomatoes grown conventionally or organically.
Findings
No significant differences in color or total soluble solids were detected. In 2003, total acidity was the only quality parameter that differed significantly between conventional and organic fruit. Conventional fruit had significantly higher soluble solids and were firmer than organic fruit.
Panelists could perceive the difference between conventional and organic tomatoes by smell or taste. Quality analyses of samples conducted on the same group of fruit used for sensory evaluation indicated no significant difference in any quality parameter except fruit firmness; with conventional tomatoes being more firm than organic tomatoes
Organic tomatoes were perceived by some of the panelists to be softer, and were preferred because of their taste, flavor, texture, and juiciness. Alternatively, conventional tomatoes were described as “not as ripe,” “dry” and having “less aroma.” The results did not conclude unequivocally that the sensory panel was truly able to distinguish conventional from organically grown fruit as a consequence of production system or if they were merely detecting a difference in ripeness.
Reference
McCollum, G, Plotto, A., Chellemi, D, Rosskopf, E., & Church, G. (2006). Postharvest quality of tomatoes produced in organic and conventional production systems. Papers presented at the workshop on Organic Agriculture: Postharvest Challenges and Opportunities, organized by the American Society for Horticultural Science Postharvest Working Group, Las Vegas, Nevada.