Mario Villarroel

Amino acid composition of Chilean hazel nuts

Abstract Samples of selected fully ripened Chilean hazel nuts growing wild in the southern part of Chile were collected for analysis. Protein and amino acid contents were determined. The protein concentration after oil extraction was 16·3%. Eighteen amino acids were found. Glutamic acid, followed by aspartic acid and arginine, were present in the greatest concentrations. Lysine was the limiting essential amino acid when compared with the FAO/WHO (1981) reference amino acid pattern, with a chemical score of 82.

Oil bodies as a potential microencapsulation carrier for astaxanthin stabilisation and safe delivery

Abstract Astaxanthin (AST) is a valued molecule because of its high antioxidant properties. However, AST is extremely sensitive to oxidation, causing the loss of its bioactive properties. The purposes of this study were to define conditions for microencapsulating AST in oil bodies (OB) from Brassica napus to enhance its oxidative stability, and to test the bioactivity of the microencapsulated AST (AST-M) in cells. Conditions for maximising microencapsulation efficiency (ME) were determined using the Response Surface Methodology, obtaining a high ME (>99%). OB loaded with AST showed a strong electrostatic repulsion in a wide range of pH and ionic strengths. It was found that AST-M exposed to air and light was more stable than free AST. In addition, the protective effect of AST against intracellular ROS production was positively influenced by microencapsulation in OB. These results suggest that OB offer a novel option for stabilising and delivering AST.

Effect of Irrigation Levels on Dissolved Organic Carbon Soil Distribution and the Depth Mobility of Chlorpyrifos

-1 , and later the natural run off was collected from the foliage to the columns. Surface irrigation was used as a control, the equivalent to 4 L h -1 weekly, plus two treatments over the columns of 6 and 8 L h -1 per pulse, respectively. Samples were obtained at three column depths: 0-5, 5-20 and 20-30 cm. The results showed that in spite of the fact that there was no interaction between depth and irrigation, a greater concentration of CHP was observed in the samples with

Characterization of Chilean hazel nut sweet cookies

A series of studies were carried out to test the effect of the incorporation of Chilean hazel nut flour in sweet cookies at the levels of 0%, 5%, 10%, 15% and 20%. The proximate chemical analysis of the different flour mixtures showed a regular increase from 7.2 to 12.2%, 14.5% to 18.8% and 1% to 2.2%, respectively, decreasing at the same time with the percentages of water and carbohydrates. Chemical amino acid scores of leucine and threonine in wheat flour improved with the incorporation of Chilean hazel nut flour. The farinographic evaluation made to the different blends showed several changes occurred with the incorporation of Chilean hazel nut flour to wheat flour. These included increase in water absorption, decrease in dough developing time and weakening of the dough. Sensory characteristics such as appearance, texture, flavor and also acceptability improved with the incorporation of Chilean hazel nut flour into the cookie formulaes.