The existence of more of 16,000 varieties of quinoa accessions around the world has caused a disregard on their structural and phytochemical characteristics. Most of such accessions belong to cultivars settled in Colombia. The goal of this research was to evaluate the structural attributes and antioxidant capacities from six quinoa cultivars with high productive potential from central regions in Colombia. This study used middle-range infrared spectroscopy (IR-MIR) to determine the proteins, starch and lipids distinctive to quinoa grains. Ultra-high-performance liquid chromatography electrospray ionization Orbitrap, along with high-resolution mass spectrometry (UHPLC/ESI-Orbitrap MS), were also used to identify the existence of polyphenols in cultivars. The antioxidant capacity was determined through DPPH, ABTS and FRAP. The spectrums exhibited significant variances on the transmittance bands associated with 2922 cm−1, 1016 cm−1 and 1633 cm−1. Moreover, the intensity variations on the peaks from the secondary protein structure were identified, mainly on the bands associated with β-Sheet-1 and -2, random coil α elice and β-turns-2 and -3. Changes found in the ratios 996 cm−1/1014 cm−1 and 1041 cm−1/1014 cm−1 were associated with the crystalline/amorphous affinity. Regarding the antioxidant capacity, great differences were identified (p < 0.001) mainly through FRAP methods, while the phenolic acids and flavonoids were determined by UHPLC/ESI-Orbitrap MS techniques. The presence of apigenin and pinocembrin on grains was reported for the first time. Titicaca and Nariño were the most phytochemically diverse quinoa seeds.

Extrusion cooking is used to produce puffed snacks based on cereals and feed ingredients. Because of its nutritional properties, quinoa flour has been employed to prepare various types of foods. This study evaluates the effects of including hyper-protein quinoa flour obtained through abrasive milling in four formulations cooked at 27% moisture content and processed in a laboratory level single screw extruder to determine their physical, textural, and pasting properties. The results indicated that additional hyper-protein quinoa flour in the cereal mixture reduced 47% the expansion index (EI), while the extrudate density (ED) and hardness increased 54 and 130%, respectively. After the extrusion process, the water absorption index (WAI), water solubility index (WSI) increased by more than 100%. The addition of hyper-protein quinoa flour (25–37%) did not affect the WAI, but an increase in the WSI was observed. The quinoa flour extrusion process generated changes on the color mainly in the L parameter, which decreased in the extruded snacks with quinoa flour inclusion (51.49), compared to the snack without inclusion (62.68). Changing the integrity of the starch granules and associated proteins, causing a decrease in the viscosity peaks during heating and subsequent cooling. The extruded samples revealed stability in the retrogradation process. Extruded snacks from quinoa could be an alternative approach to produce feed ingredients with high protein contents.

To account for the global trend towards a healthier diet, in recent years the snack market has grown substantially, with a demand for products that are more beneficial to consumers' health. Extruded snacks from a mixture of cereals, quinoa, and corn, with and without the addition of vegetables were used. Snacks made from a mixture of rice flour and quinoa high protein flour (HHP) supplied by SEGALCO S.A.S., (Popayán, Colombia) were studied. Thus, the use of sources of phenolic compounds such as Beet, Broccoli, Avocado, and Spinach, combined with sources of protein such as quinoa, can increase the nutritional quality of snack products. A combination of cereals and vegetables can produce nutrient-rich products. In this paper, phenolic compounds (given in mg AGE/g sample d.b.) and antioxidant capacity were determined using ABTS •+ , DPPH and FRAP (in mg AEAC /g sample d.b.). The highest content of phenolic compounds was found in Spinach 4% and HHP snacks (5.7 ± 0.3 and 3.5 ± 0.2 AGE/g sample d.b., respectively). Kale (2%) and Beet (4%) snacks showed a significant increase in antioxidant capacity using the ABTS •+ method. The antioxidant capacity determined using the DPPH method increased significantly in snacks made from Beet (4%), Broccoli (4%), Avocado (4%), and Spinach (4%). Using FRAP, the antioxidant capacity showed a significant increase in Kale snacks (2%) and a significant decrease in Spinach snacks (4%). In conclusion, snacks with an elevated antioxidant potential can be produced from vegetables such as kale, which can be an alternative for the food industry to develop healthier products and satisfy market trends.

Background: Interest in alternative sources of tubers and legumes has increased in recent years because of the constant search for raw materials that provide bioactive compounds with antioxidant potential benefits for consumers. The functionality of new raw materials is sought through physical and/or chemical modifications to develop and innovate new foods. The objective of this study was to characterize taro (TF) (Colocasia esculenta) and sacha inchi (Plukenetia volubilis) flours, obtained by the wet (SIF-WM) and defatted method (SIF-DM), as an alternative for the formulation of new functional foods. Methods: The free polyphenols of the different mixtures were analyzed, and the antioxidant properties of the extracts obtained were measured using ABTS.* (2,2′-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid). The ABTS radical method, which reacts with the phenolic compounds of the food matrix, using Trolox as a standard. The blends were subjected to pasting analysis, flow profile tests, determination of viscoelastic properties (temperature sweep). Characterization of common microorganisms in these foods was performed. Results: The highest protein value was obtained in the sacha inchi flour obtained by the defatted method (72.62). The majority of components in taro were carbohydrates (85.4%). About antioxidant and determination of free polyphenols, taro flour obtained values of 2.71 µmol ET/g and 7.47 mg EAG/g, higher than Sacha inchi flours. In the rheological analysis (pasting properties, flow profile, and viscoelasticity), we observed that adding taro flour in different mixtures increases the viscosity peak and a lower breakdown, while there was an increase in setback. Except for defatted sacha flour, the others presented a flow index >1 before heating, showing a dilatant fluid behavior. The presence of Taro flour improves gel formation and stability. Staphylococcus aureus and Salmonella were present in the taro flour. Conclusions: The flours analyzed represent a raw material with great potential for the development of gluten-free foods with functional properties.

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The proteins that are subjected to hydrolysis processes increase their bioactive and functional properties, for this reason, in this work the protein hydrolysis was monitored by means of spectroscopy, to determine the structural changes that proteins undergo during hydrolysis. Enzymatic hydrolysis with endo / exoproteases was carried out on the three protein isolates, the enzymes used were Alcalase 2.4L and Flavorzyme® from the Sigma laboratory. The enzyme / substrate ratio was 5%; degrees of hydrolysis between 46% and 38.4% were obtained for Quinoa protein isolate and Rice protein isolate, respectively. Both follow-up of Quinoa protein isolate and Soy protein isolate enzymatic hydrolysis was 60 minutes with Alcalasa®2.5L and 120 minutes with Flavorzima®, with respect to Rice protein isolate, the established hydrolysis times were 60 minutes with Alcalase 2.4L and 20 minutes with Flavorzima®; Times longer than these, no significant differences were observed in the degree of hydrolysis. By way of comparison, the protein isolates and their hydrolysates were studied in the mid-infrared range (4000 cm-1 to 600 cm-1) to obtain information on the structure of the protein, for this, a technique was used deconvolution of the spectrum by means of the Fourier transform function. These spectra showed significant differences in the secondary structure of the protein, regarding the analysis of the areas, which were determined using a Gaussian function; the most favorable changes were mainly in the formation of b-sheet and b-turns structures.