88E-11 |
Blanching and chitosan addition effect on "nopalitos" quality. |
L. E. ROBLES O., Dept. of Fruit and Vegetable Technology, Food Research and Develpment Center, Carretera a "La Victoria" Km. 0.6, Apartado Postal 1735, Hermosillo, Sonora, 83000, Mexico and L. D. C. Montoya B., Hermosillo, Sonora, 83000, Mexico. Nopalitos are a traditional vegetable in the Mexican diet. The main problems of quality loss that nopalitos present are browning and mucilage secretion. These reduce the consumer acceptability causing economic losses to producers of this crop. The objetive was to study the effect of blnaching and chitosan addition on color and texture of "nopalitos". Blanching effect on color and texture of nopalitos was studied (T=75° C and t=1, 2, 3 minutes). In addition chitosan was used (0.1, 0.2 and 0.3 % p/v) to prevent the secretion of mucilage in the product. Quality evaluation of nopalitos was determined as pH, titratable acidity (% citric acid) soluble solids (° Brix), texture (N), mucilage drained (ml) and color (L*, a*, b*). Once processed, the nopalitos were package in polyethilene bags and stored at 5° C for 20 days. Results show that pH, soluble solids and titratable acidity were slightly affected by conditions of time and blanching temperature, however, addition of chitosan promotes a light drop of pH and increase of the titratable acidity. Soluble solids were kept constant. Color parameters L* and b* were constant (48 to 43 and 20 to 30 respectively), but the a* value was reduced significatively (-20 to -1). Texture increased from 2.5 through 3.5 N due to treatments. Drained volume increased during storage from 5 to 25 ml. However, the addition of chitosan at 0.3% reduces significantly this effect. Increment in the blanching time produced an increase in the texture parameter (N) and a* value. Addition of chitosan during blanching could be a good alternative to reduce mucilage secretion during "nopalitos" storage and marketing.
Session 88E, Fruit & Vegetable Products: Processing
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