104C-26 |
Ultrastructural and physical properties of rehydrated anaheim chili peppers modified by low temperature blanching |
J. C. Heredia1, R. Talamás-Abbud1, V. Mendoza-Guzmán1, F. Solís Martínez2, J. Jiménez-Castro3, J. Barnard4, and A. QUINTERO1. (1) Facultad de Ciencias Químicas. Secretaría de Investigación y Posgrado, Universidad Autónoma de Chihuahua, Cd. Universitaria S/N. Apartado Postal 1542-C, Chihuahua, Chihuahua, 31170, Mexico, (2) Facultad de Medicina, Universidad Autónoma de Chihuahua, Chihuahua, Chihuahua, 31170, Mexico, (3) Facultad de Zootecnia, Universidad Autónoma de Chihuahua, Cd. Universitaria S/N, Chihuahua, Chihuahua, 31170, Mexico, (4) Food Science & Technology, Cornell Univ., New York State Agricultural Experiment Station, 630 W. North St., Geneva, NY 14456-1371 The increase in the consumption of processed pepper demands higher quality parameters; texture being one of the most important attributes. Low temperature blanching represents an important technology to achieve this. The objective of this study was to evaluate the effect of low temperature blanching and drying process on the ultrastructural and physical properties and to determine the optimum conditions to provide a final product with maximum firmness. Lots of anaheim pepper were blanched in water for 4 min at 48, 55, 65, 75 and 82 °C and maintained for holding times of 35, 45, 60, 75 and 85 min, blanched again for 4 min at 96 °C and dehydrated at 53, 60, 70, 80 and 87 °C. After the treatments, the samples were rehydrated in water at 30 °C. Rehydration ratio, texture, color and cell wall integrity changes were evaluated. The study was optimized using a second order rotatable central composite design . Texture and rehydration ratio were affected by blanching temperature and holding times (p< 0.05), the optimum response was obtained in the ranges of 59-64 °C blanch temperature, 52- 55 min holding time, and 68 °C drying temperature. Color parameter a* was correlated with temperature using an exponential model. At temperatures up to 55 °C the green color was substantially deteriorated. Microscopic evaluation of the rehydrated dried pepper showed that low temperature blanching close to the optimum conditions provides a protective effect in maintaining cell wall integrity. Notable changes occurred in the cell wall integrity outside of these conditions. The results of this process increases firmness in the rehydrated product by a factor of 2.1 times.
Session 104C, Fruit & Vegetable Products: Vegetables (Processed)
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