RESUMO
Fatty acids of forty-two samples of perirenal fat of goat kids reared on three different feeding systems: goat milk (B), milk replacer (R) and milk-based starter (F) have been analyzed by Gas Chromatography flame ionization detector. The lipids were extracted by melting of perirenal fat in a microwave oven. The fat was then filtered and dissolved in hexane. This analysis was performed on a column (100 m x 0.25 mm i.d. and 0.25 microm film thickness) coated with a polar stationary phase HP-88 and flame ionization detector was used. Hydrogen (25 psi inlet constant pressure) was used as carrier gas. Programmed temperature was kept at 175 degrees C and held isothermally for 10 min, and was then raised to 205 degrees C at a rate of 3 degrees C/min and held isothermally for 10 min. By using the fatty acids as chemical descriptors, pattern recognition techniques were applied to differentiate between goat milk, milk replacer and milk-based starter fattening diet of goat kid. C18:2 and C18:3 acids were found to be the most differentiating variables.
Assuntos
Tecido Adiposo , Dieta , Ácidos Graxos/análise , Cabras/metabolismo , Rim , Animais , Animais Recém-Nascidos , Cromatografia Gasosa , Ácidos Oleicos/análiseRESUMO
El proceso de hidrogenación llevado a cabo en la industria para obtener margarinas conlleva la formación de una cierta cantidad de isómeros trans. El consumo de este alimento así como la cantidad de estos isómeros que contiene, han sido motivo de gran controversia en las últimas décadas. Mientras que en la década de los ochenta, se consideraba saludable el consumo de margarinas, en la década de los noventa numerosos estudios indicaron que el 18:1t, incrementaba las concentraciones de LDL-colesterol y reducía los niveles de HDL-colesterol, además de asociar su ingesta con un incremento del riesgo de sufrir enfermedad coronaria. La creciente publicidad sobre los efectos desfavorables de los ácidos grasos trans parece haber influenciado a los productores de margarinas, a reducir la cantidad de estos isómeros en sus productos. Mientras tanto, Estados Unidos ha adoptado una legislación para especificar su contenido en el etiquetado de los alimentos y en Europa, Dinamarca ha limitado los niveles máximos permitidos en los alimentos
Assuntos
Humanos , Ácidos Graxos , Saúde , Margarina , Fenômenos Fisiológicos da NutriçãoRESUMO
Trans fatty acids isomers are formed during the hydrogenation process used in the food industry to harden oils. In the last decades there has been a great controversy about the consumption of margarine due to the levels of trans fatty acids they contain. While in the eighties consumption of margarines was considered healthy, during the nineties several studies indicated that consumption of 18:1t increased LDL-cholesterol levels and decreased HDL-cholesterol level, and was related with an increased risk of coronary heart disease. The publicity about the unfavourable effects of trans fatty acid consumption seems to have influenced margarine producers to reduce the trans fatty acid content of margarines. Meanwhile USA has adopted a new legislation about trans fatty acid labelling. In Europe, Dinamarca has limited the maximum level of trans fatty acids allowed in food products.