ABSTRACT
This study evaluated the in vitro effect of 3.0, 6.0, and 9.0% of green banana pulp (GBP) incorporation in fermented milk on the survival of Lactobacillus paracasei subsp. paracasei LBC 81 subjected to acid stress conditions and in the presence of bile salts. Tolerance to acid stress in pH 2.0 and in the presence of 0.30% of bile salts was evaluated right after the incorporation of the fermented milk in each of these conditions, and also during 3 and 4 h of exposure, respectively. The addition of GBP (3.0%) gives a protective effect on L. paracasei LBC 81 when exposed to stress conditions evaluated, while of 9.0% there is a marked decrease of L. paracasei LBC 81. In the absence of GBP, a decrease of L. paracasei LBC 81 is observed, but lower in the presence of GBP (9.0%).
Subject(s)
Bile Acids and Salts , Culture Media/metabolism , Cultured Milk Products , Fermentation , Lactobacillus , Probiotics , Bile Acids and Salts/metabolism , Cultured Milk Products/analysis , Hydrogen-Ion Concentration , Lactobacillus/growth & development , Lactobacillus/metabolism , MusaABSTRACT
The aims of this study were (i) to evaluate the growth kinetic of L. paracasei LBC 81 in fermented milks enriched with green banana pulp (GBP); (ii) to evaluate the effect of the incorporation of GBP on the chemical composition and the sensory acceptance; and (iii) to study the viability of the probiotic and technological properties during refrigerated storage. The amount of GBP used were 3.0, 6.0 and 9.0 g/100 g. The results show that the higher the concentration of GBP added, the shorter the time taken to reach pH 4.6. It was observed that the incorporation of GBP did not affect negatively the viability of L. paracasei LBC 81 during storage. The fermented milk elaborated with 6.0 g/100 g of GBP was the most accepted. The present study indicates that the enrichment of fermented milk with GBP favors the stability of the probiotic strain, L. paracasei LBC 81 during storage.
Subject(s)
Cultured Milk Products , Fruit , Lacticaseibacillus paracasei/physiology , Musa , Probiotics , Adolescent , Adult , Beverages , Consumer Behavior , Female , Humans , Male , Middle Aged , Young AdultABSTRACT
In this work, the rheological behaviour of emulsions (mayonnaises) stabilized by green banana pulp using the response surface methodology was studied. In addition, the emulsions stability was investigated. Five formulations were developed, according to design for constrained surfaces and mixtures, with the proportion, respectively: water/soy oil/green banana pulp: F1 (0.10/0.20/0.70), F2 (0.20/0.20/0.60), F3 (0.10/0.25/0.65), F4 (0.20/0.25/0.55) and F5 (0.15/0.225/0.625) .Emulsions rheological properties were performed with a rotational Haake Rheostress 600 rheometer and a cone and plate geometry sensor (60-mm diameter, 2º cone angle), using a gap distance of 1mm. The emulsions showed pseudoplastic behaviour and were adequately described by the Power Law model. The rheological responses were influenced by the difference in green banana pulp proportions and also by the temperatures (10 and 25ºC). The formulations with high pulp content (F1 and F3) presented higher shear stress and apparent viscosity. Response surface methodology, described by the quadratic model,showed that the consistency coefficient (K) increased with the interaction between green banana pulp and soy oil concentration and the water fraction contributed to the flow behaviour index increase for all emulsions samples. Analysis of variance showed that the second-order model had not significant lack-of-fit and a significant F-value, indicating that quadratic model fitted well into the experimental data. The emulsions that presented better stability were the formulations F4 (0.20/0.25/0.55) and F5 (0.15/0.225/0.625).
No presente trabalho, foi estudado o comportamento reológico de emulsões adicionadas de polpa de banana verde utilizando a metodologia de superfície de resposta e também foram investigadas a estabilidade das emulsões. Foram desenvolvidas cinco formulações, de acordo com o delineamento para superfícies limitadas e misturas, com as proporções respectivamente: água/óleo de soja/polpa de banana verde: F1 (0,10/0,20/0,70), F2 (0,20/0,20/0,60), F3 (0,10/0,25/0,65), F4 (0,20/0,25/0,55) e F5 (0,15/0,225/0,625). As propriedades reológicas foram realizadas em reômetro Haake Rheostress 600, com sensor de geometria cone e placa (60-mm diâmetro, 2º ângulo de cone), usando uma distância de abertura de 1mm. As emulsões mostraram comportamento pseudoplástico e foram descritas adequadamente pelo modelo Lei da Potência. O comportamento reológico foi influenciado pelas diferentes proporções de polpa de banana verde e também pelas temperaturas (10 e 25ºC). As formulações com alto teor de polpa (F1 e F3) apresentaram maior tensão de cisalhamento e viscosidade aparente. Relativo à metodologia de superfície de resposta, descrita pelo modelo quadrático, pôde-se observar que o coeficiente de consistência aumentou com a interação entre a polpa de banana verde e a concentração de óleo de soja e a água contribuiu com o aumento do índice de comportamento para todas as amostras de emulsões. A Análise de Variância mostrou que o modelo de segundo ordem não apresentou falta-de-ajuste com valor F significativo, indicando que o modelo quadrático representou bem os dados experimentais. As emulsões que apresentaram melhor estabilidade foram as formulações F4 (0,20/0,25/0,55) e F5 (0,15/0,225/0,625).
