Efecto del pre tratamiento de Deshidratación osmótica en piña (Ananas comosus; variedad Cayenne lise) en la cinética de Secado utilizando un secador de bandejas con corriente de aire.

Abstract

This study has evaluated the effect of the osmotic dehydration pre-treatment in drying kinetics of pineapple (Ananas comosus, Cayenne lise variety). The concentrations of sugar used for the osmotic solution were 30, 35 and 40 Brix degree. Air-blown temperatures tested were 60 y 70 Celsius degree and drying times of 5; 5,5 and 6 hours. All of the samples analyzed showed similar drying kinetics. The sugar gaining and humidity loss values are directly related with final concentration of soluble solids and blow-drying air temperature. During drying, a falling rate period was present, through this; it occurs the diffusion process for which effective diffusivities were calculated by the diffusion model based on the second Law of Fick. By a sensory analysis it was determined that dehydrated pineapple elaborated under the following conditions: 40 percent of final concentration of soluble solids, 70 Celsius degree of blow dryer air during 5hours is acceptable. Also the same sensory analysis showed for smell, color and taste parameters a score of 4.1, 4.1 and 4.4 points over 5 respectively, showing to be more acceptable than Nature’s Heart commercial brand. Furthermore, microbiological quality was established for the pondered best treatment by the tasters, which accomplished microbiological criteria of safety and Escherichia coli absence established by Peruvian Health Standards: Microbiological Criteria of Health Quality et Safety for Human Food and Beverage Consumption, due to the absence of a National normative. Finally, the analysis of bioactive compounds content (vitamin C, total polyphenols and carotenoids) determined the quality of the process and therefore of the product.