36E-76

G. R. ORTIZ-HERNÁNDEZ¹, E. López-Enríquez², C. Saucedo-Veloz³, and E. Mercado-Silva¹. (1) Dept. de Investigación y Posgrado en Alimentos, Univ. Autónoma de Querétaro, Centro Universitario S/N, Querétaro, 76010, Mexico, (2) Dept. de Investigaciòn y Posgrado en Alimentos, Univ. Autónoma de Querétaro, Centro Universitario S/N, Querétaro, 76010, Mexico, (3) Colegio de Posgraduados, Montecillo, Estado de México, Texcoco, Mexico

Because of overproduction of guava in México, new markets are needed as well as developmental work to control the ripening process and allow for a longer distribution time. Our objectives were 1) to measure the physiological response in guava which is minimally processed and stored at different temperatures and 2) to analyze the effects of 1 Methylcyclopropene (1-MCP) on the ripening process of intact fruit. Guava ripe fruits were peeling (1 min in NaOH 2% at 85° C), washed and stored at different temperatures (0, to 15° C) under wet air flow. Every three days the respiration rate was measured by gas chromatography. In other experiment, mature green guava fruit were treated with an air flow with 1-MCP (0-1.2 ppm) for different times (0-5 h); after the fruit was stored at 10° C under an air flow wet during 30 days. Every 4 days the color (hue value) and penetration force (N) was measured using a texture analyzer. After seven days of storage, the respiration rate in all fruit minimally processed was three to eight times higher than respiration rate of intact fruit (50 mL CO2/ kg h) indicating high sensibility of this fruit to minimal processing; at 0° C the respiration rate reached 457 mL CO2/ kg h. The application of 0.6 ppm of 1-MCP during 3-5 h in mature green fruit and stored at 10° C for 30 days, delayed the color changes (hue value 84) and maintained high the penetration force (13N) in comparison with control fruit (hue value 79 and penetration force 4N). The minimal processing in guava fruit increased strongly the metabolism decreasing its potential use in this fruit. However, the application of 1-MCP showed possibilities to increase the shelf life of intact fruit and to facilitate their distribution

Session 36E, Fruit & Vegetable Products: General
8:30 AM - 12:00 PM, Monday AM Room Hall I-2

2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana