Julliana Izabelle Simionato

Action of successive heat treatments in bovine milk fatty acids

The action of successive pasteurization thermal treatments (75 oC for 15 s) and commercial sterilization by indirect heat exchange (140 oC for 6 s) was analyzed on the lipid profile of bovine milk. Raw milk samples were submitted to pasteurization and then were submitted to sterilization (ultra-high temperature, UHT). The fat of raw milk, pasteurized milk and commercially sterilized milk samples was extracted. After transesterification, the fatty acid methyl esters (FAMEs) were analyzed by gas chromatography with flame ionization detector (GC-FID). The quantification of fatty acids (FA) revealed that for most of the found fatty acids there was no significant difference (p > 0.05) between raw milk and pasteurized milk. However, it was found significant differences for 21 of the 26 analyzed fatty acids (p > 0.05) for the raw and sterilized milks, including the predominant isomer of the conjugated linoleic acid (CLAc9t11) of the milk. This fact evidences the successive action of heat treatments on milk lipid profile.

Method validation for simultaneous determination of cholesterol and cholesterol oxides in milk by RP-HPLC-DAD

O escopo da presente pesquisa foi desenvolver e validar uma metodologia para extracao simultânea de colesterol e oxidos de colesterol utilizando saponificacao direta em amostras de leite fluido para posterior analise por cromatografia liquida de alta eficiencia em fase reversa com deteccao por arranjo de diodos (RP-HPLC-DAD). Foram avaliados os parâmetros analiticos de seletividade, linearidade e faixa de aplicacao, precisao inter e intradia, recuperacao, limites de deteccao e quantificacao do metodo. Os resultados demonstraram que a metodologia pode ser empregada com seguranca e confiabilidade para analise do colesterol e oxidos do leite. The aim of the present work was to develop and validate a reversed-phase highperformance liquid chromatography with diode array detection (RP-HPLC-DAD) method for determination of cholesterol and cholesterol oxides extracted from milk samples. The method consisted of direct samples saponification and analytes extraction, followed by their determination using RP-HPLC-DAD. Suitable analytical selectivity, linearity and range of application, intra-assay and intermediary precision, recovery, detection and quantification limits (LOD and LOQ) were achieved and, the results showed that the developed RP-HPLC-DAD method can be applied to routine determination of cholesterol and cholesterol oxides in milk samples.

Correlation between Intake and Composition of Fatty Acids in Meat from Lambs Fed Diets Containing Soybean Hulls.

The present study aimed to evaluate the correlation between the composition of fatty acids in the diet and Longissimus dorsi muscle of lambs diets containing different levels of soybean. The experiment was conducted at the campus UESB, Itapetinga-Ba, Brazil. In a randomized design,

Correlação entre os Ácidos Graxos Monoinsaturados da Dieta com os Ácidos Graxos da Carne de Cordeiros Santa Inês Alimentados com Dietas Contendo Níveis Crescentes de Casca de Soja

Objetivou-se avaliar a correlacao entre os acidos graxos monoinsaturados da dieta com os acidos graxos do Longissimus de cordeiros Santa Ines alimentados com dietas contendo niveis crescentes de casca de soja. O experimento foi desenvolvido na UESB em Itapetinga-Ba. Foram utilizados 25 ovinos Santa Ines, confinados, machos inteiros, cujos tratamentos consistiam em diferentes niveis de substituicao do milho pela casca de soja (testemunha, 25, 50, 75 e 100%) e silagem de capim elefante como volumoso. Apos esse periodo, os animais foram abatidos e as amostras do Longissimus foram coletadas e embaladas a vacuo para posteriores analises. Para analise dos dados, foi calculado o coeficiente de correlacao de Pearson, entre a composicao dos acidos graxos consumidos com a composicao dos acidos graxos encontrados na carne. As correlacoes encontradas entre os acidos graxos consumidos e os encontrados na composicao da carne demonstram que a dieta fornecida aos animais modificou o perfil de acidos graxos. DOI:10.15528/2176-4158/rcpa.v14n2p196-198