Abstract:© Versita Sp. z o.o. The purpose of this study was to evaluate the decay of squalene and the formation of trans fatty acids (TFAs) in the amaranth oil extracted with hexane with and without heat. Oils were analyzed by determining their chemical values, and the fatty acids were identified and quantified by using Fourier-transform infrared (FTIR) spectroscopy, in the mid-region of 400-4000 cm -1 , and gas chromatography. The FTIR analysis shows that two oil extracts (with and without heat) present a well-defined peak at 968 cm -1 , which represents the trans double bonds. The quantified TFAs are <0.5 g per 100 g of oil, which is considered as TFAs-free. The squalene content in the oil extracted without and with heat are 6.98±1.1% and 7.12±1.3%, respectively. Our data suggest that the TFAs formation is directly promoted by thermal processing and that squalene content is not affected by the application of heat during the oil extraction process in amaranth.

Winteraceae), a native Chilean species, has potential for use as a botanical insecticide. This species contains chemicals with biological activity, such as isoprenoids and polyphenols. In this study, the effects of the essential oil and hydrolate of D. winteri on adults of Aegorhinus superciliosus were determined in the laboratory. This species is one of the most important pests associated with the cultivation of blueberries in Chile. The insecticidal effect of both distillates was determined for five concentrations of the essential oil and hydrolate of D. winteri, with ten replicates, in a completely random bioassay. The effects of these preparations on the egglaying, hatching and feeding activity of A. superciliosus were also evaluated. The essential oil produced 100% mortality at the highest concentration (40% v/v), whereas the greatest effect of the hydrolate was 12% at 100% v/v. Ovicidal and anti-feeding effects were found for both distillates. In addition, a preliminary analysis was performed with gas chromatography coupled with mass spectrometry. This analysis detected the presence of polyphenolic secondary metabolites.

The Araucanía region is a berry producing area where important behavioral aspects of species in the genus Aegorhinus, a pest that affects crops, are still unknown. The objectives of this study were to determine the distribution, abundance and richness of these species in agroecological zones of La Araucanía Region and to determine the hosts in which they were found. The sites where these species were found were represented on a map divided into grids of 25 x 25 km. Eight species of Aegorhinus were found in the area, and Aegorhinus nodipennis and Aegorhinus superciliosus were the most abundant. The diversity was analyzed using the Shannon-Wiener index, and the equitability was determined using the Pielou index. The agroecological zone with the greatest diversity of the region corresponded to mountain ranges; however, the central plain registered the highest abundance of individuals. This study introduces new hosts for six of the eight species found in the region.

ResumenObjetivo: identificar la repercusión que tienen las crisis generadas por el sistema neoliberal en la construcción epistemológica de las Ciencias Sociales. Metodología: investigación cualitativa en la que se utilizó el trabajo documental y el método hermenéutico con base, principalmente, en una lectura diacrónica de los documentos y en el análisis crítico de éstos. Las categorías en las que se centró el estudio fueron: "crisis del sistema neoliberal", "movimientos sociales anti neoliberales" y "giro epistemológico". Resultados: las luchas y demandas populares generadas por las limitaciones del sistema neoliberal repercuten en las reflexiones y formulaciones teóricas en el continente americano.

No abstract

In the present investigation, the extraction and subsequent characterization of the collagen in the swim bladder of catfish was developed, for which a total of twelve experimental units were analyzed, distributed in three samples with four repetitions per analysis distributed under a completely randomized design with a 0,05% of significance, the size of the experimental unit 200g of lyophilized collagen. Protein, minerals, water, pH, hydroxyproline were then quantified in addition to the microbiological assays. The results obtained correspond to 76.86% of protein, 9.02% of humidity, 14.12% of ash, while for pH 4.55, hydroxyproline 44,08% and ausence of UFC/g were reported. It is determined that it can be used in food formulations to improve the texture due to its hydroxyproline content.

The objective of this research was to determine the quality of the protein present in sausages fortified with quinoa as a substitute for animal protein, through the identification and quantification of amino acids, using gas chromatography and precolumn derivatization. The amino acid composition found in the analyzed products was predominantly composed of: Threonine (THR) with a concentration of 1046.32µmol / L, aminobutyric acid (ABA) with a concentration of 9685.68 µmol / L and glutamic acid (GLU) with a concentration of 1178.71 µmol / L. These values were found in the treatment with the highest percentage of quinoa flour, establishing a directly proportional relationship between the concentrations of these amino acids and the percentage of quinoa. Gas chromatography was an adequate technique for determining the amino acid profile due to its speed and sensitivity. Keywords: amino acids, sausages, quinoa, derivatization, gas chromatography. RESUMEN La presente investigación tiene por objetivo determinar la calidad de la proteína presente en embutidos fortificados con quinua como sustituyente de la proteína animal, a través de la identificación y cuantificación de aminoácidos mediante la aplicación de cromatografía de gases y la derivatización precolumna. La composición de aminoácidos encontrada en los productos analizados destaca la presencia mayoritaria de: Treonina (THR) con una concentración de 1046,32 µmol/L, ácido aminobutírico (ABA) con una concentración de 9685,68 µmol/L  y ácido glutámico (GLU) con una concentración de 1178,71 µmol/L, todos estos valores se presentaron en el tratamiento con mayor porcentaje de harina de quinua estableciéndose una relación directamente proporcional entre las concentraciones de estos aminoácidos y el porcentaje de adición de quinua en los tratamientos estudiados. Se puede concluir que la cromatografía de gases empleada resultó una técnica adecuada para la determinación del perfil aminoacídico por la rapidez y sensibilidad presentada sobre las muestras estudiadas.  Palabras claves: aminoácidos, embutidos, quinua, derivatización, cromatografía de gases.