Cosecha y agregado de valor en fibra cashmere de cabras criollas neuquinas

Abstract

Esta tesis aborda la producción y el procesamiento textil de fibra cashmere obtenida de cabras Criollas Neuquinas (CCN) en la zona norte de la provincia de Neuquén. Dentro del sistema productivo, las cabras son la principal fuente de ingresos de la población rural. El cashmere representa un complemento interesante para la producción tradicional de carne de chivito. Los vellones de estas cabras presentan una doble capa de fibras entremezcladas, una fina y suave (cashmere) y una gruesa (pelo).La calidad está determinada principalmente por el diámetro, el rendimiento o proporción de cashmere en relación al peso total del vellón, la longitud y el color. El cashmere tiene un patrón anual de crecimiento y muda. La muda se produce a fines del invierno e inicios de la primavera y la cosecha puede hacerse mediante la esquila o el peinado. Una vez cosechada la fibra debe descerdarse como primer paso en el procesamiento textil. El descerdado permite la separación mecánica del cashmere y del pelo. Las características de la materia prima y el equipo utilizado determinan la eficiencia del proceso. En este trabajo se realizaron dos ensayos: 1)se compararon métodos de cosecha (esquila preparto versus peinado preparto) y épocas de cosecha (esquila preparto versus esquila posparto); 2) se evaluó la eficiencia del proceso de descerdado en lotes de cashmere peinado y esquilado. Los resultados demostraron que el método y la época de cosecha afectan la calidad y la cantidad de cashmere que producen las CCN. El momento óptimo para la cosecha es al preparto. Con la esquila se cosecha más fibra que con el peinado (mayores pesos de vellón) pero de menor calidad y con la desventaja de dejar a los animales desprotegidos ante inclemencias climáticas. Por eso se recomienda el peinado como método de cosecha. Se descarta la esquila posparto por la calidad deficiente. La esquila o el peinado como métodos de cosecha implican diferencias sustanciales en el proceso de descerdado. A igual configuración y pasajes por la descerdadora, los lotes peinados tuvieron mayores rindes y menores diámetros y contenido de pelos que los lotes esquilados preparto y posparto. Según el tipo de materia prima que se quiera procesar se deberán utilizar diferentes configuraciones (velocidad de cilindros y ecartamiento) en la descerdadora. Para el cashmere esquilado es importante la clasificación por tipo de vellón, ya que incide sobre los rindes, diámetros y contendido de pelos al final del proceso.

This thesis addresses the production and textile processing of cashmere fiber obtained from Criolla Neuquina goats (CCN) raised in the northern area of the Neuquén province. Within the livestock production system the goats is the main source of incomes of the rural population, being the use of cashmere an interesting complement to the traditional production of kid meat. The fleeces of these goats have a double layer of intermingled fibers, a thin and soft (cashmere) and a thick (hair). The quality of the cashmere is determined mainly by the diameter, the yield or proportion of cashmere in relation to the total weight of the fleece, the length and the color of fibers. Cashmere has an annual pattern of growth and moulting. The moulting occurs in late winter and early spring, this period being the optimal time for harvest. This practice can be done alternately by shearing or combing the animals. Once the fiber is harvested, it must be dehaired, as the first step in textile processing. The dehairing is a process that allows the mechanical separation of cashmere and hair. The characteristics of the raw material and the equipment used determine the efficiency of the process. Based on this background, two trials were conducted, one focused on primary fiber production and another focused on textile fiber processing. In the first trial, harvest methods at pre-kidding (shearing versus combing) and harvest time (pre-kidding shearing versus post-kidding shearing) were compared. In the second trial, the efficiency of the process of dehairing in batches of combed and sheared cashmere was evaluated. It was shown that both the method and the harvest time affect the quality and quantity of cashmere produced by the CCN. The results of this work showed that the optimal time for fiber harvest is in pre-kidding. With the shearing greater weights of fleece are harvested than with combing, but of lower quality and with the great disadvantage of leaving the animals unprotected against inclement weather. Based on this, combing is recommended as a method of harvest. Post-kidding shearing is discarded, unless it is used as a cleaning shear for animals that have been previously combed in preparation for the next year's harvest. It is very important the classification and conditioning of the fiber prior to the dehairing. The quality of the raw material affects the process and the final product obtained. Shearing or combing as harvesting methods imply substantial differences in the process of dehairing, mainly due to the amount of hair that must be separated in each case. At the same settings and passages through the dehairing machine, the combed batches had greater yields and smaller fiber diameters and hair content than the (pre kidding and post kidding) sheared batches. Depending on the type of raw material to be processed (combed or sheared cashmere), different configurations (rollers speeds and clearance settings) must be used in the dehairing. For the sheared cashmere the classification by type of fleece is important, since it affects the yields, fiber diameters and hair content at the end of the process.