Contenido de nutrientes minerales en leches de vaca y derivados de Argentina / Mineral nutrient content in cow milk and dairy products in Argentina

Cow milk and dairy products supply essential inorganic elements for humans, and constitute the most important source of bioavailable calcium in our diet. In order to obtain data about mineral nutrient composition of dairy products that are produced and sold in Argentina, the contents of Ca, P, Mg, Na, K, Fe, Zn and Cu in whole and low fat fluid milk, dried milk and yogurt were analyzed. P was assessed by a colorimetric method, and the other elements by atomic absorption spectroscopy. In raw milk, the mineral content shows a certain degree of variability, in addition to the variability introduced by the different processing conditions, in order to meet the requirements prescribed by trade regulations and to produce dairy products. In all cases, skimming increases the concentration of mineral nutrients, which is especially remarkable in Ca contained in skimmed milk powder. In yogurt, added milk solids like dried milk or evaporated milk appreciably increase the mineral content, even more so if ultrafiltrates are used. These ultrafiltrates increase the Ca/P ratio, which probably improves Ca bioavailability. The results obtained in these analyses provide data that are not yet available from the National Table of Food Composition, and which prove necessary and fundamental for nutritional and dietary evaluation.

[Composition of chicken and quail eggs]. / Composición de huevos de gallina y codorniz.

Qualified food composition data on lipids composition are needed to evaluate intakes as a risk factor in the development of heart disease. Proximal composition, cholesterol and fatty acid content of chicken and quail eggs, usually consumed or traded, were analysed. Proximal composition were determined using AOAC (1984) specific techniques; lipids were extracted by a Folch's modified technique and cholesterol and fatty acids were determined by gas chromatography. Results corroborate the stability of eggs composition. Cholesterol content of quail eggs is similar to chicken eggs, but it is almost the half content of data registered in Handbook 8. Differences may be attributed to the analytical methodology used to obtain them. This study provides data obtained with up-date analytical techniques and accessory information useful for food composition tables.

[Investigation needs on carotenoids in the republic of Argentina]. / Necesidades de investigación sobre carotenoides en la República Argentina.

There are no national dietary surveys regarding nutrient intake of Argentine population. On the other hand, nutrient content of foods in Argentina, as in other Latin American countries, is unknown because there are no data on food composition. Therefore, nutrient intakes must be calculated using foreign composition tables. In relation to vitamin A nutritional status, high prevalence of low vitamin A intake and low plasma retinol levels have been found in the eighties in several groups of university students. In this report, results of a 7-day dietary survey of students attending the course of Nutrition in the Universities of Buenos Aires, Luján and Tucumán are presented. Information was processed in a PC Computer (VAN Program, Lujan University, Argentina) to obtain the mean daily intake of carotenes with and without provitamin A activity, according to the German Food Composition Tables. The results showed that provitamin A carotenes provided between 40 and 82% of the vitamin A recommended allowances and that about 20% of the population had total carotene intake lower than 4 mg/day. These results are in agreement with other dietary surveys carried out in students in previous years and are a consequence of some characteristic feeding habits of the Argentine population. In order to obtain more reasonable results regarding actual intakes in our population, study of the composition of national foods would be imperative.

Contenido de vitamina C en jugo de limón fresco y procesado / C vitamin content in fresh and processing lemon juice

La vitamina C incluye dos formas activas, ácido ascórbico (AA) y ácido dehidroascórbico (ADHA), que funcionan como un sistema redox interconvertible. El nivel de vitamina C en vegetales está condicionado por factores de orden climático y agronómico, por el manejo poscosecha y las condiciones de almacenamiento. Por tratarse de un nutriente extremadamente lábil, se producen pérdidas o deterioro durante su procesamiento. En los vegetales recién cosechados la vitamina se encuentra mayormente como AA, pero gradualmente pasa a ADHA, su forma oxidada. El ADHA es muy inestable y al escindirse su anillo lactónico se pierde la actividad vitamínica. A los efectos de determinar el nivel de vitamina C en jugos de limón fresco y procesado, tal cual lo adquiere el consumidor, se analizó el contenido de vitamina C y de sus formas biológicamente activas, en muestras tomadas al azar en supermercados y negocios minoristas. Los resultados obtenidos demuestran que en los jugos analizados, los tiempos de poscosecha, las condiciones de almacenamiento y el procesado influyen notablemente sobre el contenido de la vitamina

Contenido de vitamina C en jugo de limón fresco y procesado / C vitamin content in fresh and processing lemon juice

La vitamina C incluye dos formas activas, ácido ascórbico (AA) y ácido dehidroascórbico (ADHA), que funcionan como un sistema redox interconvertible. El nivel de vitamina C en vegetales está condicionado por factores de orden climático y agronómico, por el manejo poscosecha y las condiciones de almacenamiento. Por tratarse de un nutriente extremadamente lábil, se producen pérdidas o deterioro durante su procesamiento. En los vegetales recién cosechados la vitamina se encuentra mayormente como AA, pero gradualmente pasa a ADHA, su forma oxidada. El ADHA es muy inestable y al escindirse su anillo lactónico se pierde la actividad vitamínica. A los efectos de determinar el nivel de vitamina C en jugos de limón fresco y procesado, tal cual lo adquiere el consumidor, se analizó el contenido de vitamina C y de sus formas biológicamente activas, en muestras tomadas al azar en supermercados y negocios minoristas. Los resultados obtenidos demuestran que en los jugos analizados, los tiempos de poscosecha, las condiciones de almacenamiento y el procesado influyen notablemente sobre el contenido de la vitamina (AU)

[Nutrient content in raw and processed foods derived from cereals and legumes. I: Centesimal composition and energetic value]. / Contenido de nutrientes en materias primas y productos procesados derivados de cereales y leguminosas. I: Composición centesimal y valor energético.

Proximate composition and metabolizable energy of raw and processed foods derived from cereals and legumes, were determined. Results can be used to revise the out of day national composition table, to incorporate data of ash, new data of dietary fiber obtained by an enzimatic hydrolysis method, asimilable carbohydrates and metabolizable energy. They also replace the composition of various foods which were compiled from foreing tables. Difference observed on values of lipids in those foods with low lipid content, are imputed to the solvents used in the extraction.