Resumo
The effects of the addition of Origanum syriacum L. essential oil (OE) on the lipid and protein oxidation, and sensory attributes of cooked chicken meat were compared with those of synthetic commercial meat preservatives. Ground deboned and skinless chicken breast and thigh meat were distributed according to six treatments: (T1) control (no addition of meat preservative); or the addition of (T2) 100 ppm OE; (T3) 150 ppm OE; (T4) 300 ppm L-ascorbic acid (E-300); (T5) 5 and 14 ppm butylated hydroxyanisoleadded to breast and thigh meat, respectively, (BHA/E-320); and (T6) 150 ppm sodium nitrite (E-250). Meat samples were cooked and analyzed for lipid oxidation (TBARS levels) and protein oxidation (carbonyl levels) on days 0, 4, and 7 days of storage. In addition, cooked meat thigh patties were evaluated for cooking loss and sensory attributes. All additives were showed significant lipid and protein antioxidant effects (p 0.05) compared with the control treatment during storage, with the strongest effects obtained with OEat 150 ppm and E-250. Cooking loss was not influenced (p>0.05) by the treatments. The best sensory attribute scores were obtained with OEat 150 ppm and E-250 treatments. L-ascorbic acid and BHA also showed significant effect (p 0.05) on both lipid and protein oxidation values, and sensory attributes. Based on the results study, it concluded that OEat 150 ppm may be used in replacement of synthetic antioxidants to improve the storage stability of chicken meat.(AU)
Assuntos
Animais , Carne/análise , Óleos Voláteis , Galinhas , OriganumResumo
The effects of the addition of Origanum syriacum L. essential oil (OE) on the lipid and protein oxidation, and sensory attributes of cooked chicken meat were compared with those of synthetic commercial meat preservatives. Ground deboned and skinless chicken breast and thigh meat were distributed according to six treatments: (T1) control (no addition of meat preservative); or the addition of (T2) 100 ppm OE; (T3) 150 ppm OE; (T4) 300 ppm L-ascorbic acid (E-300); (T5) 5 and 14 ppm butylated hydroxyanisoleadded to breast and thigh meat, respectively, (BHA/E-320); and (T6) 150 ppm sodium nitrite (E-250). Meat samples were cooked and analyzed for lipid oxidation (TBARS levels) and protein oxidation (carbonyl levels) on days 0, 4, and 7 days of storage. In addition, cooked meat thigh patties were evaluated for cooking loss and sensory attributes. All additives were showed significant lipid and protein antioxidant effects (p 0.05) compared with the control treatment during storage, with the strongest effects obtained with OEat 150 ppm and E-250. Cooking loss was not influenced (p>0.05) by the treatments. The best sensory attribute scores were obtained with OEat 150 ppm and E-250 treatments. L-ascorbic acid and BHA also showed significant effect (p 0.05) on both lipid and protein oxidation values, and sensory attributes. Based on the results study, it concluded that OEat 150 ppm may be used in replacement of synthetic antioxidants to improve the storage stability of chicken meat.
Assuntos
Animais , Carne/análise , Galinhas , Óleos Voláteis , OriganumResumo
The objective of this study was to evaluate the antifungal activity of nanoemulsions encapsulating essential oil of oregano (Origanum vulgare), both in vitro and after application on Minas Padrão cheese. Nanodispersions were obtained by the phase inversion temperature method. Cladosporium sp., Fusarium sp., and Penicillium sp. genera were isolated from cheese samples and used to evaluate antifungal activity. Minimal inhibitory concentrations of non-encapsulated and encapsulated oregano essential oil were determined, and they were influenced by the encapsulation of the essential oil depending on the type of fungus. The antifungal activity of the nanoencapsulated oregano essential oil in cheese slices showed no evidence of an effect of the MICs, when applied in the matrix. On the other hand, an influence of contact time of the nanoemulsion with the cheese was observed, due to the increase in water activity. It was concluded that nanoencapsulated oregano essential oil presented an inhibitory effect against the three genera of fungi evaluated. If environmental parameters, such as storage temperature and water activity, were controlled, the inhibitory effect of nanoemulsions of oregano oil could possibly be greatly improved, and they could be presented as a potential alternative for the preservation of Minas Padrão cheese against fungal contamination.(AU)
Assuntos
Queijo/microbiologia , Antifúngicos/análise , Óleos Voláteis/análise , Origanum , Emulsões , Cladosporium , PenicilliumResumo
Este trabalho de Mestrado teve por objetivo avaliar a atividade antifúngica in vitro e em queijo Minas Padrão de duas formulações (A e B) de nanoemulsões encapsulando óleo essencial de orégano (Origanum vulgare) produzidas pelo método da temperatura de inversão de fases (método PIT). Cladosporium sp., Fusarium sp. e Penicillium sp. foram os fungos identificados nas amostras de queijo Minas Padrão deteriorados. Tais cepas foram utilizadas na avaliação da atividade antifúngica in vitro e em queijo Minas Padrão do óleo de orégano nanoemulsionado. Nos testes in vitro foram determinadas as concentrações mínimas inibitórias (CMI) do óleo essencial de orégano puro e nanoemulsionado sobre o Cladosporium sp., Fusarium sp. e Penicillium sp. Foram utilizadas fatias de queijo Minas Padrão para avaliar o efeito inibitório das nanoemulsões contendo óleo essencial de orégano. Por último foi avaliado o efeito inibitório das nanoemulsões durante o processo de maturação de queijos Minas Padrão. Determinaram-se valores de CMI para óleo essencial puro de 0,2; 0,3 g/ml para Fusarium sp. e Penicillium sp., respectivamente. Enquanto para as duas formulações de nanoemulsão; os valores de CMI dependeram da quantidade de óleo essencial de orégano que estava contido nelas, obtendo-se valores de 0,26; 0,11 e 1,62 g/ml para a formulação A de óleo de orégano nanoemulsionado sobre Cladosporium sp., Fusarium sp. e Penicillium sp., respectivamente, e CMIs de 0,32; 0,1 e 0,8 g/ml para a formulação B de nanoemulsão sobre os mesmos gêneros de fungos. Os ensaios nas fatias de queijo evidenciaram que o efeito das CMIs, quando aplicadas na matriz alimentícia, foi nulo, permitindo o desenvolvimento normal dos fungos avaliados, da mesma forma se determinou a importância da atividade de água no crescimento fúngico. Já nos queijos em ambiente de maturação o efeito inibitório do óleo de orégano foi pouco satisfatório, o que indicou a importância do controle dosdemais parâmetros ambientais no ambiente de maturação. Pode-se concluir que o óleo essencial de orégano nanoemulsionado apresentou efeito inibitório contra os gêneros de fungos avaliados. Quando controlados parâmetros ambientais como temperatura de armazenamento e atividade deágua, seu efeito inibitório pode ser amplamente melhorado, apresentando-o como potencial alternativa na conservação dos alimentos
This Master Thesis aimed to evaluate the in vitro antifungal activity and in Minas Padrão cheese of two formulations (A and B) of nanoemulsions encapsulating essential oil of oregano (Origanum vulgare) produced by the method of phase inversion temperature (PIT method). Cladosporium sp., Fusarium sp. and Penicillium sp. fungi were identified in deteriorated cheese samples. These strains were used in the evaluation of antifungal activity of oregano essential oil nanoemulsions, both in vitro and in cheese. Minimum inhibitory concentrations (MIC) of essential oil of pure oregano oil and nanoemulsions were determined. Cheese slices were used to evaluate the inhibitory effect of nanoemulsions containing essential oil of oregano. Finally the inhibitory effect of encapsulated oregano oil was tested during cheese ripening. MIC values determined for pure essential oil were 0.20 and 0.3 g/ml for Fusarium sp. and Penicillium sp., respectively. As for the two nanoemulsion formulations, MIC values depended on the amount of essential oil of oregano which was contained therein, and the values for formulation A were 0.26, 0.11 and 1.62 g / ml for Cladosporium sp., Fusarium sp. and Penicillium sp, respectively. For formulation B, the values of MIC were 0.32, 0.10 and 0.80 g/ml. The tests on the cheese slices showed that the effect of MIC when applied in the food matrix was null, as the fungi growth was not avoided. As for the tests during cheese ripening, the inhibitory effect of oregano oil in nanoemulsions was unsatisfactory, which indicated the importance of controlling other environmental parameters in the maturation chamber. It can be concluded that the nanoemulsions of essential oil presented inhibitory effect against the genera of fungi evaluated. Controlled environmental parameters such as storage temperature and water activity, its inhibitory effect can be highly improved, and the nanoemulsions of oregano oil can be seen as a potential system for food preservation.