Usando la técnica de espectrometría gamma y protocolos estandarizados, a nivel latinoamericano, se midió la actividad específica en Bq kg-1 de productos alimentarios y agua, ambos productos fueron adquiridos directamente en los supermercados. Los descendientes de uranio y torio, así como isótopos antropogénicos, no fueron encontrados. K 40 es el único isótopo natural presente en los productos.

Usando la técnica de espectrometría gamma y protocolos estandarizados, a nivel latinoamericano, se midió la actividad específica en Bq kg-1 de productos alimentarios y agua, ambos productos fueron adquiridos directamente en los supermercados. Los descendientes de uranio y torio, así como isótopos antropogénicos, no fueron encontrados. K 40 es el único isótopo natural presente en los productos.

No abstract available

Dissertation (MInstAgrar (Plant Protection))--University of Pretoria, 2006. | No abstract available | Microbiology and Plant Pathology | MInstAgrar (Plant Protection) | restricted

Water sorption isotherms and effective moisture diffusivities were determined at 20 degrees C for sponge cakes at high water activity as a function of their initial porosity, in the range 86 and 52% (0 g/g dry basis fat content), and of their fat content, ranging between 0 and 0.30 g/g dry basis (67% initial porosity). The equilibrium moisture values were not affected by food structure and decreased with increasing fat content. The effective moisture diffusivity decreased from 7.5 to 0.3 X 10(-10) m2/s with increasing moisture content from 0.30 to 2.20 g/g dry basis. Decreasing initial porosity from 86 to 52% decreased effective moisture diffusivity by more than four orders of magnitude. This behaviour was related to differences of water transfer mechanisms, with the contribution from liquid water diffusion in the solid matrix and from vapour water diffusion in pores. Increasing fat content of 0.30 g/g dry basis in sponge cake, independently of porosity, decreased effective moisture diffusivity by more than five orders of magnitude. A predictive mathematical model was used to simulate moisture intake in two-composite food systems: sponge cakes with varying initial porosities and fat contents and an agar gel as a model of a non-rate limiting water source. Increasing the density of the structure or addition of fat in the cereal-based phase could increase shelf life of composite foods.

Objective: We assessed the extent of energy misreporting from the use of a self-administered 7-day diet record (7-DDR) and a widely used food frequency questionnaire (FFQ) compared to total energy expenditure from doubly labeled water (DLW) in a group of postmenopausal women. Design: At baseline, 65 healthy postmenopausal women were instructed to fill out the National Cancer Institute's (NCI) FFQ and a 7-DDR. Average total energy expenditure using the DLW method was also performed at baseline. Results: On average, the women underestimated total energy intake compared to total energy expenditure assessed from DLW by 37% on the 7-DDR and 42% on the FFQ. Conclusions: These findings suggest that the interpretation of findings from the 7-DDR- and FFQ-based energy-disease association studies in postmenopausal women needs further evaluation. Sponsorship: This research was supported (in part) by the Intramural Program of the NIH (National Cancer Institute).

F. Baah, 'Characterization of water yam (D. alata) for existing (amala, boiled yam and pounded yam) and potential food products', 2006

Em dois viveiros povoados com juvenis de pacu (Piaractus mesopotamicus) foram estudadas algumas variáveis físicas, químicas e biológicas da água, durante o período de 105 dias, com coletas quinzenais pela manhã (9:00 horas). Estes viveiros foram submetidos a diferentes tratamentos de acordo com o manejo alimentar: um deles com fornecimento diário de ração; o outro, sem arraçoamento durante 60 dias, sendo, após este período, iniciado o fornecimento de ração aos peixes por 30 dias. A avaliação limnológica da água mostrou que as variáveis estudadas presentaram pequenas flutuações durante o estudo. O curto tempo de residência da água nos viveiros proporcionou uma oxigenação adequada, impedindo o acúmulo de nutrientes a níveis tóxicos, como amônia e nitrito. Apesar do arraçoamento diário no viveiro 1 (V 1), os valores de nutrientes, condutividade, alcalinidade, entre outros, foram mais baixos do que no viveiro 2 (V 2). O curto tempo de residência da água do V 1 (1,61 dias), comparado ao V2 (2,22 dias), pode ter afetado essas variáveis. Não foram observadas flutuações acentuadas entre superfície, meio e fundo para os parâmetros analisados. PALAVRAS-CHAVE: Viveiros, manejo, variáveis limnológicas, piscicultura, pacu.

We investigated changes in the physicochemical characteristics and functional components of the Saengsik cereal grains-milled rice, brown rice, glutinous rice, and barley- by washing with electrolyzed water. There were no changes in the composition of all cereal grains that was dried with hot-air and freeze-dried after being washed with electrolyzed water. The L and a values were not affected by drying in milled rice, brown rice, glutinous rice, or barley, but the b value increased in milled rice and glutinous rice-this increase was greater with hot-air drying than with freeze-drying.

The use of natural colourings in food products presents nutritional advantages, and certain pigments are associated with functional properties, e.g. antioxidant effects. This can be very advantageous in food products with high fat contents like mayonnaises. The aim of this work was to study the effect of adding natural pigments, lutein and phycocyanin, to the water and oil phases, respectively, of oil-in-water pea protein-stabilized emulsions, beyond the desirable and expected development of a green colour. The emulsions were prepared with 3% (w/w) pea protein, 65% (w/w) vegetable oil, and varying concentrations of lutein and phycocyanin (0.25–1.25% w/w). Emulsions containing both pigments, in different proportions (total pigment concentration of 0.5%, w/w) were also prepared. Oscillatory and steady-state measurements, as well as droplet size distribution and textural profile tests, were performed. The addition of lutein to the disperse oil phase promoted a decrease of the emulsions’ rheological and textural parameters, while the addition of phycocyanin to the water (continuous) phase resulted in an increase of these properties. When using combinations of both pigments, an increase of the rheological and textural parameters with phycocyanin proportion was apparent, and a synergetic effect due to the presence of both pigments was found.