39B-33

M. I. FERNáNDEZ-CRISPIN¹, J. Welti-Chanes, and A. Lopez-Malo. (1) Dept. Ingenieria Quimica y Alimentos, Universidad de las Americas-Puebla, Sta. Catarina Martir, Cholula, Puebla, 72820, Mexico

Important tomato postharvest losses are reported around the world. In Mexico its price may vary up to 1000% depending on its availability. There are a lot of tomato processed products that involve expensive technologies and quality losses.

The objective of this study was to develop a high moisture tomato product using the hurdle technology approach.

Tomatoes (var. Saladet) of uniform maturity (bright red color) were employed. Impregnation studies with a solution containing NaCl (2.5%), glucose (6.0%), potassium sorbate (1000 ppm), sodium benzoate (1000 ppm), calcium chloride (0.15%), and citric acid (0.5%), were carried out at 5°C. During 10 days, pH, °Bx, NaCl concentration, calcium concentration (atomic absorption spectroscopy), sodium benzoate and potassium sorbate concentration, and aw were determined in tomatoes and solution. Stability of the product during a 60 days storage at 5, 15 or 25°C was also evaluated, determining color, °Bx, pH, sensory acceptability (9 point hedonic scale, 1 dislike extremely to 9 like extremely) and microbial load.

Calcium incorporation decreased tomato pH and improved texture and yield. Final product contained 1.25% NaCl, 264 ppm calcium, 585 ppm potassium sorbate, 500 ppm of sodium benzoate, aw 0.99, pH 3.6, and °Bx 7.1. Microbial growth was inhibited for at least 60 days of storage at 5°C and delayed for 40 days at 15°C. Sensory evaluation during storage demonstrated that the product maintained a high score for texture (7 to 8), color (7 to 8), flavor (6 to 8), and overall acceptability (6 to 8) for 60 days at 5°C.

A high quality tomato product with an extended shelf life and sensory characteristics similar to those of the fresh was developed using the hurdle approach.