Ultrassom e compostos químicos na sanitização de repolho roxo (Brassica oleracea var. Capitata)

• Autor(a) principal: Duarte, Ana Lucia Almeida
• Data de Publicação: 2016
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/8103
• topic: Cloreto de Benzalcônio; Dicloroisocianurato de sódio; Sanitização; Compostos clorados; Surfactante; Microscopia; Salmonella Typhimurium; Adesão bacteriana; Sanitization; Bactericides; Chlorinated compounds; Surfactant; Microscopy; Bacterial adhesion; Ciência e Tecnologia de Alimentos; Bactericidas; Salmonella; 664

Food industry has a high challenge due to increased demand for ready to eat food. Consumer demands food of fast preparation, nutritious, with similar characteristics to natural and safe from a microbiological point of view. Purple cabbage is the most consumed Brassicacea in Brazil. It has antioxidant compounds as anthocyanins and is often eaten raw. The step of sanitization of food is very important to ensure safety of raw food. So, there is interest in compounds and treatments that can provide microbiological quality and safety to food without change their physicochemical characteristics, nutritional and sensory. The objective of the present study was to evaluate the single and combined effect of using chlorinated compounds (sodium hypochlorite and sodium dichloroisocyanurate), surfactant (benzalkonium chloride) and ultrasound (40kHz) on sanitization of purple cabbages and the impact of these treatments in microbiological, physical-chemical and sensory characteristics after sanitization and during storage for 7 days at 8 ± 1 °C. Were performed analyzes of aerobic mesophilic bacteria, filamentous fungi and yeasts, lactic acid bacteria, coliforms 35 ºC; E. coli, total acidity, pH, total soluble solids, color, anthocyanins, mass loss, and inactivation/removal of Salmonella enterica Typhimurium intentionally adhered to the purple cabbage. It was also carried out sensory analysis of purple cabbages treated with sodium dichloroisocyanurate combined or not with ultrasound and control (treated only with water). Results were assessed by ANOVA, regression analysis or Duncan’s test with level of probability of 5%. Statistical analyzes were performed using software Genes®. After applying the treatments to purple cabbage, the mesophilic aerobic bacteria count was reduced from 0.33 to 2.52 log cfu.g -1 , total coliforms between 0.26 and 1.90 log cfu.g-1 , lactic acid bacteria between from 0.01 to 3.23 cfu.g-1 and fungi and yeasts from 0.10 to 0.66 log cfu.g-1 . Benzalkonium chloride combined or not ultrasound showed better results for reducing bacterial groups. However, this sanitizing was the most damaged and impossible to maintain the physico-chemical characteristics of purple cabbage samples. The reductions caused by treatment with ultrasound were statistically similar to those found to chlorine compounds, in the reduction of microorganisms present in cabbage, except for lactic acid bacteria. Ultrasound combined with sodium dichloroisocyanurate increased by 1 log cycle removal of Salmonella cells adhered to purple cabbage compared to sodium dichloroisocyanurate used alone. Regarding sensory analysis, color and texture differences were not detected between treatments using sodium dichloroisocyanurate alone and combined with ultrasound when compared to the control sample in the sensory test multiple comparison. The samples showed good overall acceptance since the consumers did not detect any difference between treatments and control sample (p> 0.05). This study showed the ultrasound's ability to replace chlorinated compounds in reducing microbiota of purple cabbage and its efficiency in the removal/inactivation of Salmonella Typhimurium cells intentionally adhered to the cabbage surface when combined with these compounds.