Qualidade microbiológica de melões minimamente processados / Microbiological quality of minimally processed melons

O consumo de frutas minimamente processadas tem aumentado em função da sociedade moderna que procura hábitos de vida mais saudáveis. O objetivo desta pesquisa foi o de analisar a qualidade microbiológica de melões minimamente processados comercializados em hipermercados da cidade de João Pessoa, Paraíba. A pesquisa foi realizada com doze amostras de melões minimamente processados. As análises microbiológicas foram realizadas para coliformes termotolerantes (45° C) e Salmonella spp. sendo os resultados comparados com os padrões legais. Observou-se que a totalidade das amostras apresentaram valores <10 NMP/g para coliformes a 45º C e ausência de Salmonella spp. Estes resultados indicaram a eficiência das Boas Práticas de Fabricação (BPF) no controle de qualidade destes produtos.

Influence of different calcium and boron salts on cell wall degradation of melon plants caused by erwinia carotovora var. carotovora

The effect of different 10-6-103 M calcium nitrate, calcium sulfate, calcium chloride, calcium hypophosphate or calcium carbonate as well as 10-100 ppm sodium tetraborate on the activity of cellulase, pectinase, cell wall degrading enzymes and proteases was studied applying the colorimetric methods of assay. The results showed that raising the salts concentration was accompanied by a concomitant reduction in the activity of such enzymes. Furthermore, calcium nitrate, calcium sulfate and calcium hypophosphate were more effective inhibitors than the other test salts. In the meantime, using mixtures of calcium salts and sodium tetraborate revealed that borate + calcium nitrate or borate + calcium sulfate were more effective than the other mixtures

Reducing the severity of bacterial soft rot of melon by applying calcium and boron mixtures

Applying borate + calcium nitrate + calcium sulfate in moderate concentrations [in vitro or in vivo] definitely attenuated the extracellular cell wall degrading enzymes produced by Erwinia carotovora var. Carotovora. The obvious decrease in the activities may be associated with the presence of both calcium and borate. The results indicated that the disease severity was reduced to the maximum value of 10% by using 5 x 104 M borate + 105 M calcium sulfate plus 10-5 M calcium nitrate. This effective mixture significantly increased radicle and hypocotyl lengths and decreased the fresh of the whole seedling, whereas the dry weights were insignificantly affected. The results indicated that the average pH remained close to alkalinity by the end of the incubation period. The resistance of melon seedling may be attributed to the presence of high levels of calcium which form calcium complex with pectic substances rendering the resistance to hydrolysis