17F-17 |
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L. D. ARGÜELLES-PIÑA1, L. C. Pérez-Velázquez1, A. Valdez-Fragoso1, J. Welti-Chanes2, A. López-Malo2, and H. Mújica-Paz1. (1) Facultad de Ciencias Quimicas, Universidad Autonoma de Chihuahua, Av. Universidad S/N, Chihuahua, 31170, Mexico, (2) Ingenieria Quimica y Alimentos, Universidad de las Americas-Puebla, Cholula, Puebla, 72820, Mexico Pickling jalapeño pepper at room temperature allows to retain desired textural properties, but the penetration rate of pickling solutes into the pepper tissue is very low. It has been reported that mass transfer rate may be accelerated in solid-liquid systems by vacuum impregnation. The aim of this work was to study the influence of vacuum impregnation, sodium chloride and acetic acid concentration on mass transport parameters during pickling of jalapeño pepper. Whole jalapeño peppers were immersed in pickling solutions containing sodium chloride (10-15%) and acetic acid (2.3-3.2%), during pre-determined relaxation times (0.3-30 days). The product/solution ratio was 1:5 (w:w). Impregnation time (five minutes), vacuum pressure (120 mbar) and calcium chloride concentration (0.2%) were held constant. Pickling treatments were conducted at atmospheric pressure in similar pickling solutions and equivalent processing times. Moisture (AOAC method), acidity (by titration with phenolphthalein), sodium chloride (salt meter Atago), calcium (atomic absorption spectrophotometry) were determined for each experimental point. Each experimental point and analytical determinations were conducted in triplicate. Response surface methodology was applied. Correlations between the dehydration-impregnation parameters and independent variables were significant (p£ 0.05). The most important factor affecting solute gain was pickling time at vacuum and atmospheric conditions (p £ 0.05). Higher water loss rates were obtained at atmospheric pressure, while solute gain predominated in the vacuum treatment. The maximum solute gain (6.53 %) obtained at atmospheric pressure and 30 days of processing, was attained in 15 days under vacuum conditions. These results have important implications for reducing pickling time.
Session 17F, Food Engineering: Kinetics and mass transfer
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