Impacto da aplicação do ultrassom nos parâmetros de qualidade em suco misto de laranja e cenoura com adição de prebiótico

• Autor(a) principal: Machado, Bruna Gasparini
• Data de Publicação: 2021
• 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/10/15035
• topic: Nutrição; Termossonicação; bebida vegetal; caracterização; subject.br-rjbn

Non-thermal food preservation methods such as ultrasound are alternatives to traditional methods, providing nutritional benefits with an innovative characteristic. The modern consumer`s interest in beverages such as fruit and vegetable juices is a reflection of the global trend of consumption of health-promoting foods, with blended juices being an alternative to ultra-processed beverages. An incorporation of prebiotic substances, such as fructooligosaccharide (FOS), into the primary mixed juice or as beneficial health characteristics. For this, the ultrasound was researched in mixed orange and carrot juice with the addition of FOS, which is a product with high added value compared to conventional juices. In this context, the objective of the present work was to evaluate the impact of treatments with ultrasound (110W, 40 kHz, 5 minutes) combined with temperature (40°C, 50°C and 60°C) on microbiological, physicochemical and compound aspects bioactives and physical characteristics of the juice during storage (25 days, 6°C). Untreated juice was considered a control, and untreated juice added with prebiotic and pasteurized juice was also evaluated. The juice was prepared in an industrial blender with a 7:3 ratio of orange and carrot with the addition of 3.2% of FOS, without the addition of water or preservatives. Microbiological assays were performed by plating with PCA medium, PDA and petrifilm plates for aerobic mesophilic, filament fungi and yeast and coliform assays at 35 °C, respectively. Total titratable acidity was performed by titration with a 0.1 N NaOH solution, pH by the potentiometric method and total soluble solids with an analog refractometer. Instrumental color analysis was performed in colorimeter, carotenoids and ascorbic acid by high performance chromatography and by RP-18 column, respectively, and the phenolic compounds and antioxidants were quantified using the Folin-Ciocalteu reagent and DPPH radical test, respectively. Turbidity was calculated using a spectrophotometer, sedimentation was calculated based on the sedimentation index and microscopy using an optical microscope. Microbiological analyzes of aerobic mesophiles, filamentous fungi and yeasts and coliforms at 35 °C did not identify significant changes between treatments and times. The treatments did not affect the values of total titratable acidity, pH, color, carotenoids, ascorbic acid, phenolic compounds, antioxidant compounds and turbidity. Total soluble solids showed a significant difference between the control juice and the other treatments studied. Time affected turbidity, ascorbic acid and antioxidant compounds values over the 25-day storage time. Ultrasound treatments at 40°C/5 minutes and 60°C/5 minutes delayed the sedimentation process. Microscopic analysis identified changes in cell structure and extravasation of intracellular fluid, which may confer desirable characteristics on juices treated with ultrasound. The weather affected the values of turbidity, ascorbic acid and antioxidant compounds. However, the ultrasound treatment preserved the characteristics of fresh orange and carrot juice with the addition of prebiotic, with no significant impacts on microbiological and physicochemical characteristics, as well as on bioactive compounds, which can be justified by the low-severe process parameters in the technology of barriers applied in this research.