Antioxidant effect of water and acetone extracts of Fucus vesiculosuson oxidative stability of skin care emulsions

A water and an acetone extract of the Icelandic brown algae Fucus vesiculosus were evaluated as potential natural sources of antioxidant compounds in skin care emulsions. To assess their efficacy in inhibiting lipid oxidation caused by photo- or thermoxidation, they were stored in darkness and room temperature as control conditions, and compared to samples stored under accelerated conditions (light and room temperature, or darkness and 40°C). The presence of extracts in the skin care emulsions induced remarkable colour changes when the emulsions were exposed to light, and more extensively under high temperature. High temperature also caused greater increments in the droplet size of the emulsions. The analysis of the tocopherol content, peroxide value and volatile compounds during the storage revealed that, whereas both water and acetone extracts showed (at 2 mg/g of emulsion) protective effect against thermooxidation, only the water extract showed antioxidant activity against photooxidation

Determination of the chemical composition and functional properties of shrimp waste protein concentrate and lyophilized flour Determinação da composição química e das propriedades funcionais de concentrado protéico e de farinha liofilizada de resíduos de camarão

Wastes from the seafood industry can be easily processed into products with new forms of use. The present study was aimed at determining the chemical composition and functional properties of shrimp waste protein concentrate and lyophilized flour. The raw material used in this study consisted of waste (head) of Litopenaeus vannamei. The protein concentrate was obtained by ethanolic extraction, being subsequently submitted to drying in oven at 70° C, while the flour was obtained by lyophilization of shrimp wastes. Moisture, ash, protein and calcium contents showed significant difference between fresh shrimp head waste samples (IN) and protein concentrate and lyophilized flour samples. The protein content for protein concentrate (PC) and lyophilized flour (LF) showed significant increase in relation to protein content in the waste (IN), thus showing that the process for obtaining the protein concentrate was efficient.<br>Resíduos provenientes da indústria do pescado podem ser facilmente transformados em produtos com novas formas de aproveitamento. No presente estudo, objetivou-se determinar a composição química e as propriedades funcionais de farinha liofilizada e concentrado proteico provenientes de resíduos de camarão. A matéria-prima empregada neste estudo foi constituída de resíduos (cabeça) de camarão Litopenaeus vannamei. O concentrado proteico foi obtido por extração etanólica e, posteriormente, submetido à secagem em estufa a 70° C, enquanto a farinha foi obtida pelo processo de liofilização do resíduo. Os teores de umidade, cinzas, proteínas e cálcio apresentaram diferença significativa entre as amostras de resíduo de cabeça de camarão in natura (IN) e as amostras de concentrado proteico e farinha liofilizada. O teor de proteínas para concentrado protéico (CP) e para a farinha liofilizada (FL) apresentou aumento significativo em relação ao teor proteico do resíduo (IN), mostrando, assim, que o processo de elaboração do concentrado proteico foi eficiente