Flavonoid diversity in bitter and debittered seeds of Andean lupin (Lupinus mutabilis Sweet).

Seeds of ten Andean lupin (Lupinus mutabilis Sweet) ecotypes were collected from different regions of Peru and treated with an aqueous debittering method. Both untreated and treated seeds were analyzed by using LC-MS to investigate flavonoid profiles of different ecotypes and impact of debittering process on these compounds. Thirteen isoflavones (mainly as glycosides of genistein and methoxy-genistein) and eight flavones (glycosylated apigenins and methyl-luteolins) were characterized as the main flavonoids in the seed samples. The untreated lupin seeds contained 187-252 mg/100 g (dry weight) of flavonoids. The main difference among lupin ecotypes was observed in the levels of genistein-malonylhexoside, methoxy-genistein-malonylhexoside, and methyl-luteolin-malonylhexoside. After the debittering treatment, the total flavonoid content in the seeds was decreased to 125-203 mg/100 g dry weight, the aglycones of genistein, methoxy-genistein, and methyl-luteolin being the key distinguishing compounds of ecotypes. The aqueous treatment was effective in degrading flavonoid glycosides and releasing the corresponding aglycones.

Effect of partial substitution of wheat flour by quinoa (Chenopodium quinoa Willd.) and tarwi (Lupinus mutabilis Sweet) flours on dough and bread quality.

Bread is the main important food product worldwide. In this study, eleven bread formulations were developed by partial substitution of wheat flour with quinoa and tarwi flours, to evaluate the effect on the rheological and pasting properties of mixtures, as well as on the physicochemical and textural properties of the final product. Partial substitution with quinoa flour generated similar thermomechanical and textural properties in the dough, and similar bread technological characteristics related to the control bread (100% wheat). In the case of tarwi, the increase in the concentration of this legume showed a negative effect on the bread quality parameters (specific volume, crumb porosity, textural properties, etc.). A negative technological impact of high percentages of wheat flour substitution by the mixture of both Andean flours was found, but it was contrasted with a positive effect on nutritional quality, particularly evidenced by a high content of proteins and dietary fiber. An optimal formulation considering technological and nutritional quality was obtained, presenting the maximum analyzed substitution level (13.35% quinoa flour and 6.65% tarwi flour). This study showed that these Andean grains are suitable for developing bread of good technological quality and improved nutritional profile, adding value to these underused ancestral flours.

Andean crops: kañiwa and tarwi flours used for the development of vegan gluten-free muffins.

BACKGROUND: The flours of two Andean crops, tarwi (Lupinus mutabilis) and kañiwa (Chenopodium pallidicaule Aellen), present an excellent nutritional profile for inclusion in vegan gluten-free muffin formulations. In this study, the proximal composition and techno-functional properties of tarwi and kañiwa flours, and the technological quality of batters and muffins (potato starch-based) formulated with 50% of these flours were evaluated. RESULTS: Andean flours have high protein, fiber, and fat content, and display high water and oil absorption. In premixes formulated with potato starch and Andean flours, a reduction in paste viscosity was observed due to starch dilution and lower water availability. Depending on their ability to interact with water, the batters formulated with these flours had a higher consistency. Confocal laser scanning micrographs showed that batters with Andean flours presented a complex matrix with dispersed starch granules surrounded by proteins and fiber fragments. Muffins made with Andean flours had a slightly lower specific volume than the control, but crumb hardness was not modified by tarwi flour (50%) and a mixture of tarwi (25%) and kañiwa (25%) flours. The intrinsic color of these flours modified crumb color, and their reducing sugar content also favored Maillard reactions in the crust. These color changes are desirable in gluten-free products because such products are frequently pale due to their high starch content. CONCLUSIONS: This study showed that tarwi and kañiwa flours are suitable for developing vegan, gluten-free muffins of good technological quality and improved nutritional profile, adding value to these underutilized ancestral flours. © 2022 Society of Chemical Industry.

Transcriptional Regulation of Quinoa Seed Quality: Identification of Novel Candidate Genetic Markers for Increased Protein Content.

Quinoa (Chenopodium quinoa Willd.) is a crop that has great potential for increased cultivation in diverse climate regions. The seed protein quality obtained from this crop is high concerning the requirements to meet human nutritional needs, but the seed protein content is relatively low if compared to crops such as grain legumes. Increased seed protein content is desirable for increasing the economic viability of this crop in order for it to be used as a protein crop. In this study, we characterized three genotypes of quinoa with different levels of seed protein content. By performing RNA sequencing of developing seeds, we determined the genotype differences in gene expression and identified genetic polymorphisms that could be associated with increased protein content. Storage nutrient analyses of seeds of three quinoa genotypes (Titicaca, Pasankalla, and Regalona) from different ecoregions grown under controlled climate conditions showed that Pasankalla had the highest protein content (20%) and the lowest starch content (46%). Our seed transcriptome analyses revealed highly differentially expressed transcripts (DETs) in Pasankalla as compared to the other genotypes. These DETs encoded functions in sugar transport, starch and protein synthesis, genes regulating embryo size, and seed transcription factors. We selected 60 genes that encode functions in the central carbon metabolism and transcription factors as potential targets for the development of high-precision markers. Genetic polymorphisms, such as single nucleotide polymorphisms (SNPs) and base insertions and deletions (InDels), were found in 19 of the 60 selected genes, which can be further evaluated for the development of genetic markers for high seed protein content in quinoa. Increased cultivation of quinoa can contribute to a more diversified agriculture and support the plant protein diet shift. The identification of quinoa genotypes with contrasting seed quality can help establish a model system that can be used for the identification of precise breeding targets to improve the seed quality of quinoa. The data presented in this study based on nutrient and transcriptome analyses contribute to an enhanced understanding of the genetic regulation of seed quality traits in quinoa and suggest high-precision candidate markers for such traits.

Innovatively processed quinoa (Chenopodium quinoa Willd.) food: chemistry, structure and end-use characteristics.

BACKGROUND: Quinoa (Chenopodium quinoa Willd.) flour and processed traditional Peruvian quinoa breakfast foods were studied to evaluate the effect of extrusion and post-processing on protein properties, morphology and nutritional characteristics (amino acids and dietary fibers). RESULTS: The extrusion increased quinoa protein crosslinking and aggregation observed by size exclusion high-performance liquid chromatography and the amount of soluble fibers, as well as decreasing the amounts of insoluble fibers in the processed foods. The post-processing drying resulted in additional crosslinking of large protein fractions in the quinoa products. The microstructure of the extruded quinoa breakfast flakes and heat-post-processed samples studied by scanning electron microscopy and X-ray tomography differed greatly; post-drying induced formation of aerated protein microstructures in the heat-treated samples. Nanostructures revealed by small-angle and wide-angle X-ray scattering indicated that extrusion imparted morphological changes in the quinoa protein and starch (dominance of V-type). Overall, extrusion processing only reduced the content of most of the essential amino acids to a minor extent; the content of valine and methionine was reduced to a slightly greater extent, but the final products met the requirements of the Food and Drug Organization. CONCLUSION: This study presents innovative examples on how extrusion processing and post-processing heat treatment can be used to produce attractive future food alternatives, such as breakfast cereal flakes and porridge powder, from quinoa grains. Extrusion of quinoa flour into Peruvian foods was shown to be mostly impacted by the processing temperature and processing conditions used. Protein crosslinking increased due to extrusion and post-processing heating. Starch crystallinity decreased most when the product was dried after processing. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Profile and Content of Residual Alkaloids in Ten Ecotypes of Lupinus mutabilis Sweet after Aqueous Debittering Process.

The evaluation of the level of alkaloids in edible Lupinus species is crucial from a food safety point of view. Debittering of lupin seeds has a long history; however, the control of the level of alkaloids after processing the seeds is typically only evaluated by changes in the bitter taste. The aim of this study was to evaluate the profile and residual levels of quinolizidine alkaloids (QA) in (Lupinus mutabilis Sweet) after aqueous debittering process. Samples from 10 ecotypes from different areas of Peru were analyzed before and after the process. Based on results obtained by gas chromatography and mass spectrometry, from eight alkaloids identified before the debittering process, only small amounts of lupanine (avg. 0.0012 g/100 g DM) and sparteine (avg. 0.0014 g/100 g DM) remained in the seeds after the debittering process, and no other alkaloids were identified. The aqueous debittering process reduced the content of alkaloids to levels far below the maximal level allowed by international regulations (≤ 0.2 g/kg DM).

Physicochemical and functional properties of isolated starch and their correlation with flour from the Andean Peruvian quinoa varieties.

Quinoa has been recognized as a complete food due to its balanced nutritional composition. Quinoa flour is used as an ingredient to improve the nutritional and functional characteristics of cereal-based foods. The physicochemical and functional (thermal and pasting) properties of flours and isolated starches of three Andean Peruvian quinoa varieties (Blanca de Hualhuas, BH; Rosada de Huancayo, RHY and Pasankalla, PK) were studied and the correlation among them properties were evaluated in order to explore their possible uses as a food ingredient. Proximal chemical composition of flour and isolated starches from quinoa varieties showed differences. Isolated starches from quinoa varieties showed a XRD Type A crystallinity patterns with polygonal shapes, small size, higher crystallinity degree and lower amylose content (<15%). The thermal (gelatinization temperatures and enthalpies) and pasting (temperature and time of gelatinization and viscosities) properties of flours and isolated starches showed differences and the principal component analysis demonstrated that those properties are significantly correlated to the starch and fat content. Based on the differences found among physicochemical and functional properties, isolated starch and flour of BH, RHY and PK quinoa varieties have potential as food ingredient for several cereal-based products.

Development of a fermented quinoa-based beverage.

Quinoa is a crop that originated from the Andes. It has high nutritional value, outstanding agro-ecological adaptability, and low water requirements. Quinoa is an excellent crop alternative to help overcome food shortages, and it can also have a role in the prevention of developed world lifestyle diseases, such as type-2 diabetes, cardiovascular diseases, osteoporosis, inflammatory and autoimmune diseases, etc. In order to expand the traditional uses of quinoa and to provide new, healthier and more nutritious food products, a fermented quinoa-based beverage was developed. Two quinoa varieties (Rosada de Huancayo and Pasankalla) were studied. The fermentation process, viscosity, acidity, and metabolic activity during the preparation and storage of the drink were monitored, as well as the preliminary organoleptic acceptability of the product. The drink had viable and stable microbiota during the storage time and the fermentation proved to be mostly homolactic. Both quinoa varieties were suitable as base for fermented products; Pasankalla, however, has the advantage due to higher protein content, lower saponin concentration, and lower loss of viscosity during the fermentation process. These results suggest that the differences between quinoa varieties may have substantial effects on food processes and on the properties of final products. This is a factor that should be taken into account when planning novel products based on this grain.

Effects of roasting and boiling of quinoa, kiwicha and kañiwa on composition and availability of minerals in vitro.

BACKGROUND: Andean indigenous crops such as quinoa (Chenopodium quinoa), kiwicha (Amaranthus caudatus) and kañiwa (Chenopodium pallidicaule) seeds are good sources of minerals (calcium and iron). Little is known, however, about mineral bioavailability in these grains. Thus the aim of the present study was to determine the iron, calcium and zinc potential availability in raw, roasted and boiled quinoa, kañiwa and kiwicha seeds. Potential availability was estimated by dialyzability. RESULTS: These seeds are good sources of phenolic compounds and kañiwa of dietary fiber. Their calcium, zinc and iron content is higher than in common cereals. In general, roasting did not significantly affect mineral dialyzability. Conversely, in boiled grains there was an increase in dialyzability of zinc and, in the case of kañiwa, also in iron and calcium dialyzability. CONCLUSION: Taking into account the high content of minerals in Andean grains, the potential contribution of these minerals would not differ considerably from that of wheat flour. Further studies are required to research the effect of extrusion on mineral availability in Andean grains.

Chemical and functional characterization of Kañiwa (Chenopodium pallidicaule) grain, extrudate and bran.

Cereals provide a good source of dietary fibre and other important compounds with nutritional potential, such as phenolic compounds, antioxidants, minerals and vitamins. Although native Andean cereals are known to have high nutritional value, their minor components have not been studied thoroughly. In this study, two varieties of a native Andean crop, kañiwa (Chenopodium pallidicaule), were investigated as sources of dietary fibre and specific antioxidant compounds. Two products, an extrudate and bran, were also prepared and their functional properties and bioactive compounds were determined. Both varieties were rich in total dietary fibre and lignin, and the phenolic components analyzed had high antioxidant activity. The extrudates had good functional properties, such as degree of gelatinization, sectional expansion index and water solubility index; the bran was high in bioactive compounds, such as total phenolics. In conclusion, kañiwa may offer an alternative to traditional cereals as a health-promoting food ingredient.