Desenvolvimento experimental de passa de umbu (Spondias tuberosa Arruda Câmara).

Abstract

The present work has got the following aims: 1) Setting up physical features (mass, volume, specific mass, equivalent round diameter and sphering) chemical (water content, total soluble solids and pH) initially of semi-ripe and ripe umbu and checking the alterations of these physical and chemical features (only up to the osmotic previous drying) when umbu fruit (ripe and semi-ripe) are under drying in order to obtain the withered fruit: a) by osmotic previous drying following ordinary drying (called osmotic drying) and b) by ordinary drying (in dryer) from initial average water content of umbu fruit up to the final wet content of 40, 35 and 30% b.u., at temperature of 70, 80, and 90°C. 2) Studying drying curves using the equation proposed by Page and Fick by using one, two and three series terms, and 3) finishing each type of drying and each final water content of the fruit to do a sensoring analyses of the withered product according to the aspects of taste, appearence and bulk. To study the physical and chemical alterations of the umbu fruit during the drying process, non-linear regressive analyses was made by using the computational process Statistica 5.0 and to the sensoring evaluation the computational program ASSISTST 6.1 was used, were we made statistic analyses through block factorial entirely by chance. Due to the obtained results, it was possible to conclude that: a) the mass and volume of ripe and semi-ripe umbu fruit, both in the osmotic and ordinary drying decrease esponencially during the process at checked temperatures and the equivalent sphere diameter and sphering of ripe and semi-ripe umbu go down by describing a second degree equation, however the ripe and semi-ripe umbu specific mass during drying show disperse values due to the temperature, which doesn't permit establishing equations to please these behaviors: b) from the studied equations (Page and Fick using one, two and three series terms), the one which has better set up to the experimental data in the osmotic and ordinary drying of ripe and semi-ripe umbu fruits was Page's equation; c) according to the sensoring analyses, osmotic drying, both for ripe and semi-ripe umbu, with final moisture content of 40 and 35 had the preference of tasters checking taste and appearence, however about texture, only the osmotic drying of ripe umbu with moisture content of 40% has had the preference.