Aplicação de ozônio e de revestimentos comestíveis em morangos (Fragaria ananassa Duch.) minimamente processados

• Autor(a) principal: Holtz, Selma Garcia
• Data de Publicação: 2006
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/5337
• topic: Morango; Processamento mínimo; Ozônio; Fragaria ananassa; Strawberry; Minimal processing; Ozone; Fragaria ananassa; CNPQ::CIENCIAS AGRARIAS::CIENCIA E TECNOLOGIA DE ALIMENTOS::CIENCIA DE ALIMENTOS

The culture of the strawberry (Fragaria ananassa Duch.) shows economic and social importance to Minas Gerais. This product is very much perishable. The minimum processing of strawberry is an alternative of commercialization. However, the washing and humid sanitization favors fungal growth. The sanitization with gaseous ozone and application of edible coatings are technologies that can be used in minimum processing of strawberries. The goal of this work was to adjust the technology of minimum processing of strawberry and to keep microbiological and physico-chemistry qualities of the product. The efficiency of methods of hygienic cleaning in the reduction of the initial contamination of the strawberries by aerobic mesophilic, molds, yeasts and total and thermotolerants coliforms was compared. The strawberries had been cleaned with air spurt and sanitized with ozone during 30 and 60 min. Washing of the strawberries in water followed of sanitization with chlorinated organic solution was also evaluated. The effect of the edible coatings application in the increase of the shelf-life of the minimally processed strawberries was evaluated. Camarosa organic strawberries had been harvested and selected following the manual removal of the calix. They had been submitted to the sanitization treatments with ozone or chlorinated organic solution, followed of cassava or maize starch edible coating. The strawberries had been packed and cooled 5° C for 15 days. The microbiological quality of the product was analyzed by aerobic and anaerobic mesophiles, psychrotrophic, molds and yeasts plate count and by the total and thermotolerants coliforms determination. Alterations of color express by the browning index and the total difference of color, pH, total soluble solids, firmness of the pulp, weight loss and total vitamin C, were evaluated too. All the comparisons had been made by the Analysis of Variance 5% of probability, with significance between the averages analyzed for the Tukey test. The initial population of aerobics mesophiles was reduced in the strawberries cleaned with air spurt and sanitized with ozone for 60 min. Molds and yeasts had been reduced with 30 and 60 min of ozonation. It did not have significant reduction of these microorganisms in the strawberries washed in water and, or sanitized with organic chlorinated solution. The biggest number of total coliforms was 1100 MPN/g, detected in the strawberries only cleaned with air spurt. Thermotolerants coliforms had not been detected in analyzed sample. The population of molds and yeasts presented minor variation during the storage, in the strawberries sanitized with gaseous and coated with maize starch, not having effect of the treatments on the populations of the other microorganisms. Browning index, pH, total soluble solids and firmness of the pulp had not varied in the strawberries sanitized with ozone or organic chlorinated solution and that had received or not edible coatings. The content of vitamin C was kept until 7° day of storage in the strawberries of all the treatments. The total difference of color and the weight loss had been lesser in the strawberries only ozonated. Is concluded that, in the conditions of this study, the ozonation for 60 min was efficient: (i) to reduce the initial contamination for aerobic mesophilics, (ii) to minimize the color and weight losses and (iii), to control molds and yeasts of the minimally processed strawberries when associated to the edible coating of starch maize, keeping the shelf-life of the product for a period of seven to ten days.