Potencialidades biotecnológicas da algaroba (Prosopis juliflora Sw, DC) para produção de fermento biológico.

Abstract

In present work, the broth of mesquite (Prosopis juliflora sw, DC) was used for growth of microorganisms, especially yeasts that naturally canning to be fermented. The research was developed in three steps: Selection and isolation, propagation and yeasts production. The strains of yeasts isoled were named ALG-1, ALG-2, AlG-3, ALG-4 and ALG-5 where ALG-3 and ALG-4 presented high performance in fermentation process. These strains were genetically analysed how being Saccharomyces and Zigossacharomyces type. The conditions environmental of culture were equal at alcoholic fermentation that use how culture medium juice of sugar cane and molasses. Variables were monitored and controlled through fermentor programmed with physical and chemical system sensors and projected of accord with yeast production process. The pH was maintained in 4,5; temperature of 30o C ± 2o C, and optimal concentration of substrate also was maintained in 25g/liter. The operations variables used were air flow rate per medium volume united of 0,5 v.v.m. This flow rate measured the concentration of dissolved oxygen and stirrer speed was controlled in 250 rotation per minute. The propagation of cells resulted in series dilutions for a selection and isolation of strains/ yeast into more criterions methods, and well characterized with basis in the microbiological and genetic procedures. The fermentation processes were developed in batch with agitation and aeration. The yeasts selected of the broth of mesquite were tested in juice of sugar cane where yield was higher so as the commercial yeast. The yeasts selected were previously freezed at temperatures of -40° C, -165° C and -196° C, succeeded by freeze drying process. The freeze drying at temperature of -40°C resulted in a good stabilitidy so long 4 month of stocking. The data analysis was utilized for studies of the kinetics of fermentative process and of yeast drying by liophilization. In this phase, were evaluated the influence of the better cryoprotectant medium for the maintenance of yeast cell viability. This work can show that mesquite é the big source of yeast production.