Production of innovative gluten-free breakfast cereals based on red and black rice by extrusion processing technology.

The transformation of black and red, broken or not, whole rice grains, into breakfast cereals is an interesting way to add value to these snacks for some reasons. Firstly, broken kernels hardly achieve a high market value; whole rice is healthy not only for their nutrient contents but also for their phytochemical profile, rich in phenolic compounds; breakfast cereals from pigmented rice are colored by themselves, and any additional colorant is unneeded; finally, rice is naturally gluten-free and suitable for those with conditions like celiac disease or gluten sensitivity. The objective of this study was to optimize some extrusion parameters that account for the physicochemical properties of extrudates by using response surface methodology. Feed moisture between 15 and 21% and the 4th barrel zone temperature between 110 and 160 °C were the independent variables. Specific features such as color, texture, water solubility and absorption, cold viscosity, expansion, specific volume, and compression force were evaluated. The trials have shown that moisture had a higher impact on the extrusion process than temperature. Less expanded, denser, harder, and darker products were obtained at higher moisture levels. The optimum points were defined at 15.5% and 16.0% of feed moisture and 159 °C and 150 °C of temperature for black and red rice extrudates, respectively. These conditions resulted in cereal breakfast balls with optimal water solubility, volume, texture, and good color. Additionally, cold viscosities and a low compression led to products with a potential high approval by consumers.

Functional foods for coronary heart disease risk reduction: a meta-analysis using a multivariate approach.

BACKGROUND: It has been difficult to identify the appropriate bioactive substance for the development of new functional foods associated with coronary heart disease, because the results of many clinical studies are contradictory. OBJECTIVE: The objective of this study was to use the multivariate statistical approach known as principal component analysis (PCA) followed by a mixed model to process data obtained from a meta-analysis aimed at evaluating simultaneously the effect of ingestion of 1 of 3 types of bioactive substances (n-3 fatty acids, soluble fibers, and phytosterols) on 1 or more of 4 biomarkers (plasma total cholesterol, triacylglycerol, LDL cholesterol, and HDL cholesterol). DESIGN: Five independent variables (number of patients per study, dose, age, body mass index, and treatment length) and 4 dependent variables (percentage change in blood total cholesterol, LDL, HDL, and triacylglycerol) from 159 studies and substudies were organized into a matrix. The original values were converted to linear correlation units, which resulted in a new matrix. RESULTS: Two principal components were enough to explain 63.73% and 84.27% of the variance in the independent and dependent variables, respectively. Phytosterols and soluble fibers had a hypocholesterolemic effect, whereas n-3 fatty acids lowered triacylglycerol and increased total, LDL, and HDL cholesterol. The PCA and mixed model showed that this behavior was independent of dose, number of patients per study, age, and body mass index but was associated with treatment length. CONCLUSIONS: PCA is useful for summarizing available scientific information in examinations of health claims for foods and supplements.

Effect of harvesting and drying conditions on chlorophyll levels of soybean (Glycine max L. Merr).

Chlorophyll in soybean represents a downgrading factor for the crops. Five Brazilian cultivars were harvested between R(6) and R(8) stage of development (Fehr & Caviness scale) and dried at 25 degrees and 40 degrees C. The effect of maturity stages and two drying conditions after harvest were studied to achieve reduction of moisture and chlorophylls to acceptable levels. When seeds were dried at 25 degrees C, even harvesting at early stages of development such as R(6), the green pigments were almost degraded, and 16 ppm of chlorophyll were found at maximum, accompanied by loss of moisture. Moisture and chlorophyll declines as seed matures, but at intermediary stages (R(6)-R(7)), chlorophyll degrades first, so the rate of moisture loss should not be used to predict chlorophyll contents. At 40 degrees C, complete degradation of chlorophyll pigments is only achieved when seeds are swathed from R(7) stage up, otherwise the seed quality could be compromised. Slow drying allows almost complete removal of green pigments, even when seeds are swathed a few days before the physiological maturity stage.

Relationship between color (instrumental and visual) and chlorophyll contents in soybean seeds during ripening.

The correlation between chlorophyll content and quantitative color parameters was investigated in order to find an indirect method for predicting green pigment in ripening soybean seeds. Five Brazilian soybean varieties harvested at different maturity stages (R(6) to R(8) according to the scale of Fehr & Caviness) and dried under two conditions (in oven at 40 degrees C with circulating air and at ambient temperature around 25 degrees C) were analyzed in two consecutive years. The slow-dried seeds at 25 degrees C lost chlorophyll faster, whereas drying at 40 degrees C did not result in yellowing of seeds. High and significant linear correlations between a value and total chlorophyll were obtained over the whole maturation period and on both conditions of drying. From an industrial point of view it appears that a value, obtained by the CIE-L*a*b* method, seems to be a good tool to be applied for quality control and classifying soybean seeds for different purposes.

Degradação da clorofila durante a maturação e secagem de sementes de soja / Chlorophyll degradation during maturation and drying of soybean seeds

A presença de clorofila em óleos provenientes da extração de grãos verdes reduz sua qualidade oxidativa, confere coloração escura indesejável e diminiui a velocidade do processo de hidrogemação, sendo que sua remoção eleva o custo da refinação. Da mesma forma, a presença do pigmento reduz o valor comercial dos grãos, levando a prejuízos na comercialização, frente ao enorme volume de exportação brasileira. A retenção da clorofila em sementes oleaginosas ocorre em condições de colheita prematura acoplada a estresse hídrico no campo, ou secagem rápida em estufa, porém, o mecanismo de degradação ainda não foi bem esclarecido. Neste trabalho investigou-se a degradação da clorofila e o aparecimento...