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The objective was to determine the adequate conditions for the microwave-assisted extraction of antioxidant compounds from the seed hull of sunflower hybrids. The existence of genetic and environmental variability in the phenolic content obtained under the selected extraction conditions was also analyzed. The extractions were carried out at 70 °C-20 and 90 °C-10 min, using water as solvent and a power of 600 W. The total phenol, flavonoid and antioxidant activity were evaluated. The microwave extraction process at 90 °C-10 min gave significantly higher values of total phenol (407.13 ± 6.11–512.71 ± 23.54 mg gallic acid⋅100 g−1 hull), flavonoids (210.09 ± 6.15–297.64 ± 5.68 mg catechin⋅100 g−1 hull) and antioxidant activity (76.73 ± 4.40–110.80 ± 3.51 μmol TE⋅g−1 hull) than those obtained at 70 °C-20 min. The cultivation environment also significantly affected the antioxidant yield, with total phenol and flavonoid contents being significantly higher for the hybrids grown in Balcarce than for those from Tandil. A significant interaction between hybrids and cultivation environmental was also observed for the antioxidant activity, indicating that the environmental effects were not similar among hybrids. The results of this study provide valuable information related to giving added value to a residue of the oil industry. [ABSTRACT FROM AUTHOR]

Roasted-dried peppers (Capsicum annuum L.), known as “chile pasado”, are a common food item consumed in Mexico. During processing, physicochemical changes affect the quality of this foodstuff; these changes are related to the pepper varieties used. The objective of this study was to evaluate the effect of three green peppers (Capsicum annuum L.) varieties (Anaheim, Mirasol and a G1 hybrid from a cross between Anaheim and Mirasol) on their physicochemical and structural properties during the roasting-drying process. The hypothesis was that using new and more suitable pepper varieties during the roasting-drying process, would result in better yields and quality of roasted-dried peppers. The experimental design was completely randomized with two replicates per treatment and the experimental unit was a sample of each pepper variety. Peppers were roasted under fixed conditions and dried at 75 °C. Yield, water activity (aw), moisture content, texture, pH, acidity, microstructural analysis, antioxidant activity, phenolic and capsaicinoid content, pungency, and the rehydration ratios were evaluated. Data were statistically analyzed by one-way ANOVA and a mean comparison using the Tukey’s test. The physical, chemical, and structural characteristics of hybrid G1 were similar to those of Mirasol. Roasting caused texture loss and increased antioxidant activity and phenolic and capsaicinoid contents. During drying, Mirasol and hybrid G1 showed decreased phenolic content and antioxidant activity and increased capsaicin content. The loss of firmness in dried-rehydrated tissues was 94.1-96.8 %. Hybrid G1 had improved yield compared with Mirasol; however, Anaheim peppers showed the highest yield. Additionally, phenolic and capsaicinoid content were higher in hybrid G1 than in Anaheim. Hybrid G1 exhibited advantageous functional characteristics that could be used in roasting and drying processes for the production of food ingredients. [ABSTRACT FROM AUTHOR]

The effects of different concentrations of calcium hydroxide [Ca(OH)2] and calcium lactate [C6H10O6Ca] on the functional and physical properties of extruded ( EF) and nixtamalised ( NF) blue maize flours were evaluated. Calcium source and concentration showed no significant effects on the EF expansion index. The water absorption index ( WAI) of EF decreased as the concentrations of both calcium sources increased, and NF with C6H10O6Ca had the lowest WAI. The thermal and pasting properties of NFs were higher than those of EF. NF with C6H10O6Ca showed the highest final viscosity (FinV), indicating less damage to the starch granules, and this was correlated with microscopic analysis. In contrast, the FinV of EFs was significantly affected by calcium source and concentration. Extrusion with 0.3% and nixtamalisation at 2.95% of C6H10O6Ca yielded high WAI value and the best rheological properties in maize flour, respectively. These results suggest the use of C6H10O6Ca in extrusion or nixtamalisation to produce blue maize flours for tortilla or snacks with antioxidants. [ABSTRACT FROM AUTHOR]