Abstract This work aimed to develop extrudates enriched with açaí and evaluate the effect of this fruit on their physicochemical properties and bioactive constituents of these foods. Rice/corn (2 : 1) extrudates containing 0, 2, 4, and 6% of freeze-dried açaí were prepared using a twin-screw extruder and characterized towards proximate composition, the concentration of anthocyanin and carotenoids, and typical process-related extrudate characteristics. The addition of açaí increased the total anthocyanins (from 0 to 20.1 mg 100 g-1) and total carotenoid content (from 1.6 to 6.2 µg g-1). Açaí enrichment elevated the protein and mineral content by 6.3% and 32.2%, respectively. There was no significant difference between the samples regarding the expansion index. Higher incorporation of açaí resulted in crispier snacks extrudates and high total color difference (ΔE). Therefore, açaí (up to 6%) can be regarded as stable in the extrusion conditions applied and be used in extrudates to enhance their bioactive and nutritional properties, providing color and suitable physical characteristics. Açaí extrudates can serve as an alternative for consumers interested in convenience food with bioactive constituents.

Abstract The aim of this study was to develop snack bars nutritionally enriched with Spirulina and evaluate if there was acceptance of the sensorial attributes by schoolchildren. Snack bars enriched with Spirulina (2% and 6%) and a control formulation (0% Spirulina) were prepared. The samples were evaluated regarding nutritional content, microstructure, and sensorial characteristics. Furthermore, the study of stability during storage (30 days) was carried out. The addition of 2% and 6% of Spirulina provided a protein increase of 11.7% and 29.9%, respectively. The physicochemical and microbiological parameters remained stable during the storage of 30 days. Sensory evaluation showed that snack bars enriched with 6% Spirulina presented no significant difference (p > 0.05) compared to the control samples. We concluded that Spirulina can be used as a nutritive ingredient in snack bars designed for infant feeding without sensorial characteristics change.

Abstract Nowadays the demand for practical food like snacks increases worldwide, however the nutritional value in most these formulations is reduced. Due to its chemical composition with high protein concentration, the microalga Spirulina has been used on the production of enriched foods. The present study aimed to evaluate the effects of Spirulina sp. LEB 18 addition on snacks formulations and extrusion conditions on the physicochemical and structural properties of snacks. Protein concentration and physical properties such as expansion index, bulk density, hardness, water absorption index, water solubility index and color were determined. The results showed that the addition of Spirulina sp. LEB 18, temperature in the last zone of the extruder and feed moisture influenced the product responses. The increase in feed moisture increased the hardness, bulk density and water absorption index of the snacks. Higher concentrations of microalga produced snacks with higher protein content, total color difference (ΔE) and compact structure. The addition of 2.6% Spirulina produced snacks with up to 11.3% protein and with adequate physical and structural properties for consumption. Thus, snacks containing Spirulina are an alternative to the demand for healthy food of practical consumption.

The localization of several anomalous uranium levels in Acosta zone, associated to the Balbuena and Santa Bárbara Subgroups sediments in the Salta Group, have been found by the geologist working for the Northwest Department of the National Commision of Atomic Energy between 2008 and 2010. These findings are located stratigraphically at the base of Yacoraite Formation and the upper levles of the Maíz Gordo Formation. Other findings are reported in the abnormal and thin levels of the Lumbrera and Mealla Formations. The anomalies identified on the floor of Yacoraite Formation correlate with the ore and copper values of the regional uranium level. Uranium mineralization is hosted in gray micaceous shales, dark brown pelites and organic matter- rich black levels, particularly where banks are interbedded with parallel laminated fine sandstones. Two anomalous sections were identified in the Maíz Gordo Formation, the first one located in the basal part of the upper third part of the unit and the second, close to the top of the Formation. The anomalies of the first section have a large areal distribution and show greater interest from an economic point of view.

La prospección realizada en el período 2008-2010 por el Departamento Regional Noroeste de la Comisión Nacional de Energía Atómica en la comarca Acosta (departamento Guachipas, provincia de Salta), permitió localizar varios niveles anómalos de uranio asociados a sedimentos de los Subgrupos Balbuena y Santa Bárbara del Grupo Salta. Estos indicios se ubican estratigráficamente en la base de la Formación Yacoraite y en el tercio superior de la Formación Maíz Gordo. Se menciona además el hallazgo de delgados niveles anómalos en las Formaciones Mealla y Lumbrera. Las anomalías identificadas en la base de la Formación Yacoraite se correlacionan con el nivel mineralizado regional de uranio y cobre. La mineralización de uranio se aloja en pelitas grises micáceas, pelitas pardas oscuras y niveles pelíticos negros ricos en materia orgánica, principalmente donde intercalan bancos de areniscas finas con laminación paralela. En la Formación Maíz Gordo se identificaron dos secciones anómalas, la primera de ellas localizada en la parte basal del tercio superior de la unidad y la segunda próxima al techo de la Formación. Las anomalías de la primera sección tienen una gran distribución areal y presentan mayor interés desde el punto de vista económico.