Multivariate analysis to select chemical compounds and rheological parameters as predictors of bread quality: interaction of wheat genotype and particle size of fine bran

This assay was performed to select chemical compounds and rheological parameters for the prediction of the bread volume and crumb firmness of breads made with a blend of wheat flour-fine bran, using multivariate analysis. Two main factors were used, the source of fine bran and the particle size of fine bran. The experiment consisted in a completely random design, in a 2 × 3 factorial arrangement, the statistical analysis shown that the particle size of fine bran influence almost all the analytical variables. In addition, discriminant analysis was performed to analyse which rheological parameters and chemical components show the greater influence on dough behaviour and bread quality. Biaxial extensional viscosity, farinograph consistency, dough development time and stability were the main rheological parameters that govern the specific volume and crumb firmness and, were both closely related to the fibre, protein and starch content in the flour-fine bran blends. Particle size-genotype interaction has a significant influence on gelatinisation enthalpy and biaxial extensional viscosity that change the bread volume and the crumb firmness. The simplicity of linear equation of five independent variables to predict bread quality with high levels of accuracy could be advantageous in both basic research and the routine quality control of wheat mills.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13197-021-05290-3.

Antioxidant, Antimutagenic and Cytoprotective Properties of Hydrosos Pistachio Nuts

Pistachio nuts are included among the foods with the highest antioxidant capacity. Stressed cultivating conditions, such as the use of regulated deficit irrigation (RDI), are expected to create a plant response that might increase the production of secondary metabolites. Fruits that are obtained under RDI treatments are commonly called hydroSOS products. The aim of this work was to study the influence of using different rootstocks (P. atlantica, P. integerrima, and P. terebinthus) and two RDI treatments on the antioxidant (ABTS, ferric reducing antioxidant power (FRAP), and DPPH), antimutagenic (Ames test), and cytotoxicity (MTT assay in five human cell lines) activities of pistachios. P. terebinthus showed the best antioxidant activity, and the RDI treatments maintained and improved the antioxidant properties of pistachios. Neither the rootstock nor the RDI had significant impact on the antimutagenic potential of pistachios. The nut extracts had no toxic effect on non-cancerous cells and the application of RDI did not reduce their cytoprotective capacity. Furthermore, neither rootstock nor RDI treatments affected the ability of the pistachio extracts of preventing the oxidative damage by H₂O₂. The application of RDI strategies, in addition to allowing irrigation water saving, led to obtaining pistachios with the same or even better biofunctional characteristics as compared to fully irrigated pistachios.

Sex and hormonal status influence plasma lipid responses to psyllium

BACKGROUND

The primary mechanisms by which soluble fiber lowers plasma cholesterol are well known. However, specific effects of fiber on lipoprotein metabolism and how sex and hormonal status influence these effects are not well defined.

OBJECTIVE

The effects of a psyllium supplement in men, premenopausal women, and postmenopausal women were examined to determine the mechanisms by which psyllium lowers plasma LDL-cholesterol concentrations and affects lipoprotein remodeling in the intravascular compartment.

DESIGN

We designed a crossover trial in which 24 men, 23 premenopausal women, and 21 postmenopausal women were randomly assigned for 30 d to a fiber supplement (15 g psyllium/d) or a control. Plasma lipids and cholesteryl ester transfer protein and lecithin-cholesterol acyltransferase (phosphatidylcholine-sterol O-acyltransferase) activities were measured after each treatment.

RESULTS

When compared with the control, psyllium intake lowered plasma LDL-cholesterol concentrations by 7-9% (P < 0.0001) without affecting plasma HDL-cholesterol concentrations. An interactive effect between fiber and sex and hormonal status was observed for plasma triacylglycerol. Psyllium supplementation significantly lowered plasma triacylglycerol concentrations in men by 17% and raised triacylglycerol concentrations in postmenopausal women by 16% (P < 0.01). The dietary treatment did not significantly affect plasma triacylglycerol in premenopausal women. Lecithin-cholesterol acyltransferase was unaffected by psyllium intake whereas cholesteryl ester transfer protein activity was 18% lower after psyllium supplementation than after the control treatment (P < 0.0001).

CONCLUSIONS

This trial showed that the psyllium-induced responses to plasma lipids were associated with sex and hormonal status and that psyllium, through its action in the intestinal lumen, indirectly affected the intravascular processing of lipoproteins.

Lime-treated maize husks lower plasma LDL-cholesterol levels in normal and hypercholesterolaemic adult men from northern Mexico

Lime-treated maize husks (LTCH), a by-product of tortilla manufacturing in Mexico, have been shown to decrease plasma LDL-cholesterol levels in guinea-pigs by specific alterations in hepatic cholesterol metabolism. To determine whether LTCH would also lower plasma cholesterol levels in normal and hyperlipidaemic individuals, the fibre content of a typical diet was increased by supplementing free-living subjects in North-West Mexico with cookies containing 450 g LTCH/kg. Normal subjects (n 11) with plasma cholesterol levels of less than 5.7 mmol/l and hypercholesterolaemic subjects (n 12) with plasma cholesterol levels higher than 5.7 mmol/l participated in the study. Plasma glucose, cholesterol, triacylglycerol, LDL-cholesterol and HDL-cholesterol concentrations, LDL:HDL values and blood pressure were determined at baseline and after 6 weeks of supplementation with LTCH. LTCH supplementation significantly lowered the plasma total cholesterol level by 11-15% and LDL-cholesterol by 25%, and improved the LDL:HDL value by 29-33% (P < 0.01) in both normal and hypercholesterolaemic subjects. HDL-cholesterol, triacylglycerol and glucose concentrations did not change. Both groups consumed equal amounts of LTCH per week; individuals showed excellent compliance and good acceptance of the product. Neither group changed their dietary habits during the time of the experiment as determined by 3 d dietary records at baseline and at week 6. We conclude that LTCH supplements are suitable to increase fibre intake and reduce plasma LDL-cholesterol levels in healthy and hypercholesterolaemic subjects in this population.