Bebidas lácteas fermentadas formuladas com leite, soro de leite e extrato de arroz vermelho: aspectos físicos, químicos, microbiológicos e sensorial

• Autor(a) principal: Boêno, Josianny Alves
• Data de Publicação: 2014
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/4217
• topic: Oryza sativa L; Aproveitamento de subprodutos; Desenvolvimento de bebidas; Soro lácteo; Byproducts use; Beverage development; Lactic serum; MEDICINA VETERINARIA PREVENTIVA::SAUDE ANIMAL (PROGRAMAS SANITARIOS)

The development of lactose drinks with added rice grits extract diversifies dairy market. Moreover the use of industrial co-products reduces the amount of residue formation. Therefore the purpose of this study was to elaborate fermented lactose beverages with added red rice extract (RRE) and lactic serum, a dairy co-product, in order to enrich the developed lactose beverage. Not only this is a low cost drink, but it may also contribute to the health of people who have celiac disease or milk allergy, due to the use of rice and the low levels of milk. Pasteurized milk, fresh cheese serum and natural yogurt were used. To obtain the RRE, rice grits were blended with water addition, in a 5:1 ratio. It was heated at 85 °C and blended for 2 min. The RRE was used at the following percentage 6, 10, 20, 30, and 34 %, and the lactic serum in substitution of the lactose base (LS) at 26, 30, 40, 50, and 54 %. We added 10 % sacarose and 0.3 % GFG stabiliser to the mix. After these beverages reached the temperature of 45 °C, they received 2.5 % of inoculum, and were left in thermic isolation for 5 h. Then they were cooled at 8 °C for 10 h. After this period, the samples were homogenized and stored at a 5 °C environment. The Central Rotational Composite Layout was employed, and 11 lactose fermented drink treatments were elaborated, in other words, a 22 complete factorial, including four axial points and three repetitions in the central point. Physical and chemical tests were performed (pH and titratable acidity) in the raw material in order to verify milk and serum quality , as well as in the fermented lactose beverages, soon after its elaboration and after seven, 14, 21, 28, 35, 42, 49, and 56 days at 5 °C. We performed microbiologic analyses (qualitative determination of Salmonella sp., total coliforms, coliforms at 45 °C, and the coagulase positive Staphylococci count), and centesimal mineral composition determination and syneresis; besides the apparent viscosity and the sensorial analyses test (preference and acceptability). The beverages developed were characterised for having a protein level of > 1.98 g (100 g)-1 higher than the minimum recommended by the current legislation, since being partially skimmed < 1.77 g (100 g)-1 and for having levels of lactose that are tolerated by people who have bad absorption (< 6.19 g (100 g)-1). Considerable values of Zn, Mn and Cu were obtained, levels similar to other K and Fe lactose beverages, and low levels of Na, Mg and Ca. They showed great hygienic sanitary levels and a viable level of lactose bacteria superior to 109 UFC mL-1 during storage. The acceptability was higher than 80 % amongst potential consumers, with a higher acceptability rate of beverages that contained 6 to 20 % of RRE and between 26 to 40 % of LS. This result was compatible to the viscosity and syneresis. A 28 day life span is surmised, a satisfactory span, considering the fact that no conservatives were added to the product.