Caracterização físico-química e sensorial de iogurte "light" com farinha de yacon (Smallanthus sonchifolius)

• Ano de defesa: 2010
• Autor(a) principal: Vasconcelos, Christiane Mileib
• Orientador(a): Chaves, José Benício Paes
• Banca de defesa: Fontes, Edimar Aparecida Filomeno , Pires, Ana Clarissa dos Santos
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Ciência e Tecnologia de Alimentos
• Departamento: Ciência de Alimentos; Tecnologia de Alimentos; Engenharia de Alimentos
• País: BR
• Palavras-chave em Português: Yacon; Iogurte; Espectro sensorial; Sensorial descritiva; Frutoligossacarídeos
• Palavras-chave em Inglês: Yacon; Yogurt; Sensory spectrum; Descriptive sensory; Fructoligosaccharides
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::CIENCIA E TECNOLOGIA DE ALIMENTOS::CIENCIA DE ALIMENTOS
• Link de acesso: http://locus.ufv.br/handle/123456789/2878

The yacon (Smallanthus sonchifolius) is originated in the Andean region. It is composed primarily of water (85-90 % of fresh weight) and carbohydrates (90 % dry matter), especially glucose, fructose, sucrose and fructooligosaccharides (FOS). The has last one considered a prebiotic, which works by improving intestinal flora, reducing concentration of blood lipids, inhibiting the early stages of colon cancer, among others. Considering that currently the food industry have a focus on developing products with high nutritional value and convenience, to meet consumer demand for a healthier lifestyle, this study aimed to develop yogurt "light" supplemented with yacon flour and characterize them as physical-chemical aspects (moisture, protein, fat, ash, dietary fiber and carbohydrates, color, soluble solids, pH, acidity and viscosity) and sensory (descriptive analysis by sensory spectrum method and acceptance test) and calculate the caloric value of the yoghurts. Yogurt containing 1,58; 2,56; 3,00 and 3,86 % of yacon flour and a control formulation without addition of yacon flour were analyzed. Descriptive sensory analysis of 11 sensory attributes (color, graininess, viscosity, consistency, mealy texture, residual flour, sweet taste, sour taste, yacon flavor, yacon aroma and fermented aroma) were evaluated by nine sensory trained panel using a 15 cm unstructured scale. Results of all tests were subjected to analysis of variance (ANOVA) and for those showing significant differences (p<0,01), regression models were tested. Chemical composition of yoghurt formulations allowed to classify them as restricted-fat yogurt, low calorie, containing fibers, especially yogurt with 2,56; 3,00 and 3,86 % of yacon flour that can be considered as a food source fiber and therefore prebiotics. Regarding the physical-chemical analysis showed significant variation (p <0,01) for color, soluble solids and acidity with increasing concentration of yacon flour. Viscosity also varied significantly (p <0,01) with the concentration of yacon flour at temperatures of 10 and 25 °C, with positive effect. As for the sensory evaluation results indicated that, yoghurts varied greatly in their sensory profiles. Yoghurt "light" with 3,86 % yacon flour stood out due to a higher intensity for color, graininess, viscosity, consistency, mealy texture, residual flour, yacon aroma and yacon flavor, and lower for fermented aroma and sour taste. Yoghurt "light" with 2,56 and 3,00 % of yacon flour were quite similar with respect to attributes. According to the acceptance test for sensory attributes evaluated, there was greater acceptance of those with lower concentrations of yacon flour, since it is not common this type of product, the less the consumption habit of yacon. It is concluded that the addition of yacon flour in yogurt is a viable alternative for the fermentation industry, however, more studies are needed to obtain a better matching of the sensory characteristics of them.