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Produção de um iogurte probiótico : estudo das propriedades funcionais e organoléticas
| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| Resumo, Índice, Introdução | 226.8 KB | Adobe PDF | ||
| Documento Principal | 1.17 MB | Adobe PDF |
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Abstract(s)
A inclusão de bactérias benéficas em alimentos probióticos, tem sido alvo de interesse por parte das indústrias em geral, em virtude da preocupação crescente da população por uma alimentação e estilo de vida saudáveis. A estirpe Leuconostoc citreum L3C1E7 foi isolada de um queijo artesanal da ilha do Pico, tendo demonstrado algumas propriedades probióticas em estudos anteriores. Para além de produzir um exopolissacárido (EPS), foi também demonstrado que a ingestão desta bactéria produz um efeito benéfico no sistema imunitário em animais. Esta estirpe tem assim uma enorme potencialidade para ser utilizada num alimento probiótico. No presente trabalho, foi escolhido o iogurte para testar a aplicação desta estirpe probiótica, uma vez que a produção de EPS poderá trazer vantagens funcionais a este tipo de alimento. Desta forma, pretende-se avaliar as propriedades funcionais e organoléticas de um iogurte probiótico produzido com a incorporação desta estirpe de L3C1E7. Para este estudo, foram produzidos vários iogurtes com diferentes concentrações de sacarose (0%, 2%, 5% e 10%), de modo a poder avaliar a melhor concentração para maximizar a produção de EPS e as propriedades organoléticas do produto final. Foram avaliados vários parâmetros físico-químicos, que incluíram o pH, a acidez titulável, a sinérese com base em dois métodos (método de corte e a capacidade de retenção da água), a viscosidade, a tensão superficial, os açúcares totais e os açúcares redutores. Foi ainda realizada uma análise sensorial com um painel de 35 provadores não treinados. Não se observaram diferenças significativas (P>0,05) em alguns dos parâmetros avaliados, nomeadamente no pH, na acidez titulável, na sinérese e na presença de açúcares redutores, em ambos os iogurtes produzidos. No entanto, a adição da estirpe L3C1E7 resultou num aumento significativo (P<0,05) da viscosidade nos iogurtes produzidos com sacarose. A viscosidade também aumentou com o tempo de armazenamento a 4°C (6 dias) como resultado provável da produção de EPS pela bactéria L3C1E7. A concentração de 5% de sacarose foi a escolhida para a realização das provas organoléticas. Embora não tenham sido observadas diferenças significativas (P>0,05) entre os iogurtes com e sem a incorporação da estirpe L3C1E7, nos vários parâmetros avaliados (aroma, acidez, doçura, consistência e impressão geral), observou-se uma tendência para os consumidores preferirem os iogurtes com a presença da estirpe probiótica. Podemos assim concluir que a estirpe L3C1E7 apresenta um enorme potencial para ser utilizada no fabrico de um iogurte probiótico.
ABSTRACT: The inclusion of probiotic bacteria in certain types of food has been of interest to industries in general, as the population is increasingly concerned about health and a healthier lifestyle. The strain Leuconostoc citreum L3C1E7 was isolated from an artisanal cheese of Pico Island, having shown some probiotic properties in previous studies. In addition to producing a exopolysaccharide (EPS), it was also shown that the intake of this bacterium produces a beneficial effect on the immune system in animals. Consequently, this strain has a huge potential to be used in a probiotic food. In this work, yogurt was chosen to test the application of this probiotic strain, since EPS production may bring functional benefits to this type of food. Therefore, the objective of this study was to evaluate how this L3C1E7 strain influences the functional and sensorial properties of a probiotic yogurt. For this study, several yoghurts were produced with different concentrations of sucrose (0%, 2%, 5% and 10%), in order to maximize the production of EPS and the sensory attributes of the final product. We evaluated several physico-chemical parameters, including pH, titratable acidity, syneresis based on two methods (cutting method and the water holding capacity), viscosity, surface tension, the total sugar and reducing sugars. Sensory analysis was also performed with a panel of 35 untrained tasters. No significant differences were observed (P > 0.05) in some of the evaluated parameters, including pH, titratable acidity, syneresis and reducing sugars contents of both yogurts produced. However, the addition of L3C1E7 strain resulted in a significant increase (P < 0.05) of viscosity in yoghurts produced with sucrose. Viscosity also increased with storage time at 4°C (for 6 days), possibly as a result of the production of EPS by the bacteria L3C1E7. The concentration of 5% sucrose was chosen to carry out the sensory analysis. Although the yogurts with and without the incorporation of the strain L3C1E7, did not significant differ (P > 0.05) in the parameters evaluated (aroma, acidity, sweetness, consistency and overall impression), there was a tendency for the consumers to prefer the yoghurts with the probiotic strain. We can thus conclude that the strain L3C1E7 presents a huge potential for application in the manufacture of a probiotic yogurt.
ABSTRACT: The inclusion of probiotic bacteria in certain types of food has been of interest to industries in general, as the population is increasingly concerned about health and a healthier lifestyle. The strain Leuconostoc citreum L3C1E7 was isolated from an artisanal cheese of Pico Island, having shown some probiotic properties in previous studies. In addition to producing a exopolysaccharide (EPS), it was also shown that the intake of this bacterium produces a beneficial effect on the immune system in animals. Consequently, this strain has a huge potential to be used in a probiotic food. In this work, yogurt was chosen to test the application of this probiotic strain, since EPS production may bring functional benefits to this type of food. Therefore, the objective of this study was to evaluate how this L3C1E7 strain influences the functional and sensorial properties of a probiotic yogurt. For this study, several yoghurts were produced with different concentrations of sucrose (0%, 2%, 5% and 10%), in order to maximize the production of EPS and the sensory attributes of the final product. We evaluated several physico-chemical parameters, including pH, titratable acidity, syneresis based on two methods (cutting method and the water holding capacity), viscosity, surface tension, the total sugar and reducing sugars. Sensory analysis was also performed with a panel of 35 untrained tasters. No significant differences were observed (P > 0.05) in some of the evaluated parameters, including pH, titratable acidity, syneresis and reducing sugars contents of both yogurts produced. However, the addition of L3C1E7 strain resulted in a significant increase (P < 0.05) of viscosity in yoghurts produced with sucrose. Viscosity also increased with storage time at 4°C (for 6 days), possibly as a result of the production of EPS by the bacteria L3C1E7. The concentration of 5% sucrose was chosen to carry out the sensory analysis. Although the yogurts with and without the incorporation of the strain L3C1E7, did not significant differ (P > 0.05) in the parameters evaluated (aroma, acidity, sweetness, consistency and overall impression), there was a tendency for the consumers to prefer the yoghurts with the probiotic strain. We can thus conclude that the strain L3C1E7 presents a huge potential for application in the manufacture of a probiotic yogurt.
Description
Dissertação de Mestrado, Tecnologia e Segurança Alimentar, 7 maio de 2019, Universidade dos Açores.
Keywords
Leuconostoc citreum Alimento Probiótico Iogurte Probiótico Propriedades Organoléticas
Citation
Sousa, Tanisha Marie Santos. "Produção de um iogurte probiótico: estudo das propriedades funcionais e organoléticas". 2019. 98 p.. (Dissertação de Mestrado em Tecnologia e Segurança Alimentar). Angra do Heroísmo: Universidade dos Açores, 2018. [Consult. Dia Mês Ano]. Disponível em www:<http://hdl.handle.net/10400.3/5164>.