Extraction of bioactive compounds from pecan nutshell: An added-value and low-cost alternative for an industrial waste.

The pecan nutshell [Carya illinoinensis (Wangenh) C. Koch] (PNS) is a source of bioactives with important beneficial properties for the human health. PNS represents between 40-50 % of total mass of the nut, resulting as waste without any added value for the food industry. Even though a variety of methods were already developed for bioactive extraction from this waste, unconventional methodologies, or those which apart from green chemistry principles, were discarded considering the cost of production, the sustainable development goals of United Nations and the feasibility of real inclusion of the technology in the food chain. Then, to add-value to this waste, a low-cost, green and easy-scalable extraction methodology was developed based on the determination of seven relevant factors by means of a factorial design and a Response Surface Methodology, allowing the extraction of bioactives with antioxidant capacity. The pecan nutshell extract had a high concentration of phenolic compounds (166 mg gallic acid equivalents-GAE/g dry weight-dw), flavonoids (90 mg catechin equivalent-CE/g dw) and condensed tannins (189 mg CE/g dw) -related also to the polymeric color (74.6 %)-, with high antioxidant capacities of ABTS+. radical inhibition (3665 µmol Trolox Equivalent-TE/g dw) and of iron reduction (1305 µmol TE/g dw). Several compounds associated with these determinations were identified by HPLC-ESI-MS/MS, such as [Epi]catechin-[Epi]catechin-[Epi]gallocatechin, myricetin, dihydroquercetins, dimers A and B of protoanthocyanidins, ellagitannins and ellagic acid derivatives. Hence, through the methodology developed here, we obtained a phenolic rich extract with possible benefits for human health, and of high industrial scalability for this co-product transformation.

Techno-functional properties of gluten-free pasta from hyperprotein quinoa flour.

Many consumers who are aware of the importance of good nutrition demand quality food alternatives. In particular, many of them are looking for quality, plant-based protein sources such as quinoa. The objective of this work was to evaluate the techno-functional properties of gluten-free pasta from hyperprotein quinoa flour. Pasta mixes were made from gluten-free flours, corn, rice, cassava starch, hyperprotein quinoa flour and defatted high protein quinoa flour, which were subsequently extruded. The flow rheological properties of aqueous dispersions of flour mixtures were analyzed before and after the pasting test. In addition, thermal properties were analyzed by differential scanning calorimetry and structural properties by Fourier transform infrared spectroscopy. The results showed a change of flow from dilatant (n > 1) to pseudoplastic (n < 1) after the pasting test. In addition, a positive correlation was observed between hyperprotein defatted quinoa flour and viscosity, and a negative correlation with hyperprotein quinoa flour. Regarding thermal properties, it was found that all blends showed low gelatinization enthalpy values, attributed to the high proportions of HQF and HDQF. Spectroscopic analysis showed that the extrusion did not significantly affect the native structure of the protein, by monitoring the intensities of the 1648 cm-1, 1656 cm-1 and 1667 cm-1 bands associated with the Random coil, α-helix, ß-turns secondary structures, respectively. It was possible to conclude that both hyperprotein quinoa flour and defatted hyperprotein quinoa flours have a differential influence on the techno-functional properties of pasta. The first one, tends to reduce viscosity and consistency while the second one tends to increase it. Finally, moderate temperatures during extrusion did not cause significant changes in starch and protein structures as determined by spectroscopic study.

Characterization of By-products with High Fat Content Derived from the Production of Bovine Gelatin.

Background: Gelatin is a protein obtained by partial hydrolysis of collagen contained in skins, connective tissue and/or animal bones, which are by-products of the meat industry. The main raw material to produce bovine gelatin is the dermis of the skin, but there is a variation in fat and moisture content depending on the bovine skin origin. As a contribution to the circular economy and sustainability, these by-products with high fat content and the fat released from them during the gelatin production process can be managed for food industries, mainly in the development or formulation of animal feed. Methods: For the initial physicochemical characterization, moisture, fat, protein and ashes content were determined. Once the by-products with high fat content were identified, alteration parameters such as acidity, peroxide and saponification indexes were evaluated. Additionally, thermal, rheological and fatty acid composition characterization was carried out in order to study the possible applications of the by-products. Results and Discussion: The results showed that certain by-products have a fat content of less than 15%, so the viability of their use is limited. On the other hand, some by-products have a fat content exceeding 30%; however, their extraction can only be done manually, resulting in a low efficiency process. By-products removed from the supernatant in the extractors presented fat percentages of 99.9 and 98.9%, and there exists the possibility of implementing a mechanical method for their extraction. The analysis of alteration and oxidation parameters, thermal and rheological characterization, fatty acid profile and solid fat content were exclusively conducted on these high-fat content by-products. Based on the characterization, these by-products could be valued and incorporated into animal feed formulations. Nevertheless, certain limitations exist for their use in applications such as biodiesel production or the food industry.

Elaboración de productos tipo tallarín libres de gluten y evaluación de sus propiedades fisicoquímicas / Elaboration of gluten free noodle products and evaluation of its physicochemical properties

RESUMEN La creciente demanda de productos libres de gluten ha dado lugar al estudio y desarrollo de alimentos que suplan las necesidades de los consumidores. El objetivo de esta investigación fue elaborar productos libres de gluten tipo tallarín y evaluar sus propiedades fisicoquímicas. Para ello, se empleó plátano o yuca como fuentes alternativas a la harina de trigo. Se determinaron sus propiedades fisicoquímicas. Se extrajeron harina y almidones y, a partir de ellas, se evaluaron sus propiedades térmicas, empleando calorimetría de barrido diferencial y termogravimetría. Se formularon y elaboraron productos similares a los tallarines empleando las harinas y se analizaron sus propiedades fisicoquímicas, microbiológicas y sensoriales, usando, como control, un producto comercial de trigo. La yuca presentó mayor humedad que el plátano, lo que está relacionado con su susceptibilidad a la degradación. En el análisis termogravimétrico, los productos de yuca mostraron mayor reducción de peso en la zona de alta volatilidad, asociado a la pérdida de humedad. Las harinas y los almidones de plátano presentaron temperaturas de gelatinización mayores que las registradas para los productos de yuca. La humedad y acidez de los tallarines elaborados presentaron valores dentro de la norma (NTC 1055-2014). En ambos casos, su contenido de cenizas fue superior al fideo comercial. Los tallarines elaborados, se pueden considerar inocuos, con buenos parámetros de aceptación sensorial. Estos resultados constituyen un punto de partida en el estudio y aplicación de fuentes de harinas y almidones no tradicionales, permitiendo la generación de valor agregado a cultivos de importancia en la región.

ABSTRACT The growing demand of free gluten products has shown the necessity to study and develop new products in order to supply the consumer request. The objective of this research was to elaborate gluten-free products similar to noodles and to evaluate their physicochemical properties. Plantain or cassava were employed to replace wheat flour. Physical and chemical properties were determined in plantain and cassava samples. Both, Plantain and Cassava Flour and their starches were extracted. Thermal characteristics of flour and starch were evaluated employing differential scanning calorimetry and thermal gravimetric analysis. Products similar to noodle were formulated and elaborated employing plantain or cassava flour. Noodle physicochemical, microbiological and sensorial characteristics were analyzed, employing a commercial product as a control. Cassava presented higher humidity values than plantain, it is related to their susceptibility to degradation. In thermogravimetric analysis, cassava products shown upper weight reduction in high volatility zone associated to humidity lost. Plantain flours and starches presented gelatinization temperatures higher than registered for cassava products. Both plantain and cassava noodles presented humidity and acidity values according to the legal legislation (NTC 1055-2014). Developed products showed ash content higher than commercial noodles. According to microbiological and sensorial analyses, the plantain and cassava products could be considered innocuous with good consumer acceptation. These results could constitute a starting point in the study and application of different flours and starches from non-traditional sources, which allow to increase the value of crops in the region.