Improvement of hepatic innate immunity in chemically-injured livers to develop hepatocarcinoma by a serine type-protease inhibitors enriched extract from Chenopodium quinoa.

Food ingredients have critical effects on the maturation and development of the immune system, which innate - lymphoid (ILCs) and myeloid - cells play key roles as important regulators of energy storage and hepatic fat accumulation. Therefore, the objective of this study is to define potential links between a dietary immunonutritional induction of the selective functional differentiation of monocytes-derived macrophages, ILCs and lipid homeostasis in hepatocarcinoma (HCC)-developing mice. Hepatic chemically injured (diethylnitrosamine/thiacetamide) Rag2-/- and Rag2-/-Il2-/- mice were administered with serine-type protease inhibitors (SETIs) obtained from Chenopodium quinoa. Early HCC-driven immunometabolic imbalances (infiltrated macrophages, glucose homeostasis, hepatic lipid profile, ILCs expansion, inflammatory conditions, microbiota) in animals put under a high-fat diet for 2 weeks were assessed. It was also approached the potential of SETIs to cause functional adaptations of the bioenergetics of human macrophage-like cells (hMLCs) in vitro conditioning their capacity to accumulate fat. It is showed that Rag2-/-Il2-/- mice, lacking ILCs, are resistant to the SETIs-induced hepatic macrophages (CD68+F4/80+) activation. Feeding SETIs to Rag2-/- mice, carrying ILCs, promoted the expansion towards ILC3s (CD117+Nkp46+CD56+) and reduced that of ILC2s (CD117+KLRG1+) into livers. In vitro studies demonstrate that hMLCs, challenged to SETIs, develop a similar phenotype of that found in mice and bioenergetic adaptations leading to increased lipolysis. It is concluded that SETIs promote liver macrophage activation and ILCs adaptations to ameliorate HCC-driven immunometabolic imbalances.

Chenopodium quinoa's Ingredients Improve Control of the Hepatic Lipid Disturbances Derived from a High-Fat Diet.

This study explored the effects of Chenopodium quinoa's ingredients on the major lipids' hepatic profile and the functional selective differentiation of monocyte-derived macrophages and innate lymphoid cells in mice on a high-fat diet. Six-week-old Rag2-/- and Rag2-/-Il2-/- mice received (12 days) a low-molecular-weight protein fraction (LWPF) or the lipid fraction (qLF) obtained from the cold pressing of C. quinoa's germen. At the end of the experiment, mouse serum and liver tissue were collected. The differences in triglycerides, phospholipids, and the major lipids profile were analyzed. Infiltrated monocyte-derived macrophages and innate lymphoid cells (ILCs) and the expression of liver metabolic stress-related mRNA were measured. In the Rag2-/- mice, feeding them LWPF appeared to improve, to a larger extent, their hepatic capacity to utilize fatty acids in comparison to the qLF by preventing the overwhelming of triglycerides (TGs), despite both reducing the hepatic lipid accumulation. An analysis of the hepatic major lipids profile revealed significant increased variations in the PUFAs and phospholipid composition in the Rag2-/- mice fed with the LWPF or LF. The Rag2-/-Il2-/- mice, lacking innate and adaptive lymphocytes, seemed resistant to mobilizing hepatic TGs and unresponsive to lipid accumulation when fed with the LF. Notably, only the Rag2-/- mice fed with the LWPF showed an increased proportion of hepatic CD68+F4/80+ cells population, with a better controlled expression of the innate immune 'Toll-like' receptor (TLR)-4. These changes were associated with an oriented expansion of pluripotential CD117+ cells towards ILC2s (CD117+KLRG1+). Thus, C. quinoa's ingredients resulted in being advantageous for improving the mechanisms for controlling the hepatic lipotoxicity derived from a high-fat diet, promoting liver macrophage and ILCs expansion to a selective functional differentiation for the control of HFD-driven immune and metabolic disturbances.

Techno-Functional and Rheological Properties of Alternative Plant-Based Flours.

The use of alternative vegetal sources is a proposed strategy to improve the diversity and quality of plant-based products on the market, currently led by soy and pea. This study compares the techno-functional properties of seven vegetable flours (chickpea, lentil, red lentil, white bean, quinoa, amaranth, and oat) and the rheological properties of their flour pastes and gels. All techno-functional properties significantly (α = 0.05) varied depending on the type of flour. Among the flours studied, the highest swelling capacity was for white bean and the lowest for chickpea and red lentil. Water holding capacity was high for white bean and oat flours and low for red lentil. Oat and quinoa flours had the highest oil-holding capacity. Emulsifying and foaming capacities were high for all pulse flours but poor for amaranth and oat flours. However, amaranth and oat provided a much higher viscosity during heating than the rest of the flours. The viscoelastic properties of the flour pastes indicated that they all had a gel structure with storage modulus (G') values over loss modulus (G″) values. From the viscoelastic properties, amaranth and quinoa showed a weak gel structure with low G' and G″ values, and the chickpea, lentil, and red lentil formed pastes with a high elastic contribution (high G' values). In agreement, these three pulse flours were the only ones able to form hard, self-standing gels. These results show the potential of vegetal flours from alternative sources in the development of new plant-based products.

Effect of Germination on the Nutritional Properties, Phytic Acid Content, and Phytase Activity of Quinoa (Chenopodium quinoa Willd).

The aim of this study is to evaluate the effect of desaponification, soaking, germination, and refrigerated storage on the phytase activity, phytic acid content, and nutritional properties of three varieties of quinoa: white, red, and black. Desaponification and soaking reduced the number of minerals and the nutritional content. Germination of the seeds was carried out in the desaponified samples. The nutritional values, phytase activity, and phytic acid content of quinoa were measured after 6 h of soaking and then at 4 and 7 days during germination plus 7 days of refrigerated storage (4 °C). Germination increased the fibre and protein content as well as the iron, zinc, and calcium content. Germination significantly increased the phytase activity in all varieties and decreased the phytic acid content. The phytic acid content decreased during germination from 32 to 74%. Refrigerated storage had no significant effect on most of the factors studied. Germination boosts nutritional content and phytase activity while decreasing phytic acid content. Germination can be a simple method to reduce phytic acid in quinoa and may also improve the nutritional quality of this pseudocereal with the potential for use in functional foods and vegetarian diets.

Wet milling of buckwheat cultivars and some quality properties of the fractions.

The hulled buckwheat cultivars (Aktas cv. and Günes cv.) were wet-milled, and then some chemical, yields, colour, functional properties, phenolic compound, antioxidant activity, and pasting, thermal and retrogradation properties of starches were investigated and compared with the wholegrain buckwheat flour (with hull) and buckwheat groat flour (without hull) of the same cultivars. Sodium dodecyl sulphate polyacrylamide gel electrophoresis patterns of flours and protein fractions were examined under reducing and non-reducing conditions. The hull, germ+dietary fibre, protein and starch fractions were collected. The total recovery for Aktas cv. and Günes cv. cultivars were 98.1% and 96.1%; total starch yields were 51.6% and 49.7%; pasting temperatures of the starches were found as 83.7 and 85.7°C; and final viscosities of starches were determined as 3.5 and 3.4 Pa·s, respectively. The resistant starch contents of starch fractions of Aktas cv. ve Günes cv. were found as 3.28% and 3.62%, respectively. The highest total phenolic compound contents were detected with dimethyl sulphoxide extraction in the germ+dietary fibre fractions. The highest 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and trolox equivalent antioxidant capacity were found in the hull fraction (as 81.7%) and germ+dietary fibre fraction (as 11.8 mmol/kg) of Aktas cv. cultivar.

Enrichment of Wholemeal Rye Bread with Plant Sterols: Rheological Analysis, Optimization of the Production, Nutritional Profile and Starch Digestibility.

Bread is one of the staple foods of many countries, and its enrichment with bioactive compounds is trending. This phenomenon is focused on breads with a good nutritional profile, such as wholemeal rye bread (WRB), in which enrichment with plant sterols (PSs) is allowed in accordance with European regulations. The objective of the present study was to optimize the production of a WRB enriched with PS (PS-WRB) and to evaluate the proximate composition and starch digestibility as an indicator of nutritional quality. The rheological analysis showed that the bread dough presents satisfactory farinographic properties (dough development time 6 min; stability 4 min; degree of softening 100 Brabender units) but high water absorption (67%). The PS-WRB is high in dietary fiber and low in protein (20.4 and 7.7% w/w, dry basis, respectively) compared with other cereals reported in the scientific literature. In turn, a low starch proportion was hydrolyzed during the simulated digestion (59.9% of total starch), being also slowly hydrolyzed, as deduced from the rapidly digestible starch value (56.5% of total starch). In conclusion, WRB is a suitable matrix for PS enrichment, which allows for obtaining a product with a good nutritional profile and potential health benefits.

Effect of Different Black Quinoa Fractions (Seed, Flour and Wet-Milling Coproducts) upon Quality of Meat Patties during Freezing Storage.

In this study, the quality of meat patty samples containing different black quinoa fractions (seed, flour and wet-milling coproducts) was evaluated during freezing preservation. Composition, physicochemical parameters (aw, pH, colour and texture), cooking properties, lipid oxidation and sensory characteristic were studied in four batches (control and 8% concentration of quinoa seed, flour and wet-milling coproducts added) at 30, 60 and 90 days of freezing (-20 ± 1 °C). Different black quinoa fraction addition affected (p < 0.05) physiochemical properties, improved cooking properties and reduced lipid oxidations during freezing storage. Batches with flour and wet-milling coproducts added were the most stable for texture parameters and lipid oxidation during freezing. The results obtained showed that quinoa wet-milling co-products could be considered a valuable sustainable and organic food ingredient, maintaining nutritional and global qualities of the fresh meat product. In addition, freezing storage is an effective way to prolong the shelf life of patties with different black quinoa fractions, added without affecting quality.

Intestinal Intervention Strategy Targeting Myeloid Cells to Improve Hepatic Immunity during Hepatocarcinoma Development.

Innate immunity in the tumor microenvironment plays a pivotal role in hepatocarcinoma (HCC) progression. Plant seeds provide serine-type protease inhibitors (SETIs), which can have a significant influence on liver inflammation and macrophage function. To elucidate the influence of SETIs to counter pro-tumorigenic conditions, at the early stages of HCC development, it was used as an established model of diethylnitrosamine/thioacetamide-injured liver fed with a standard diet (STD) or high-fat diet (42%) (HFD). The administration of SETIs improved survival and ameliorated tumor burden via modulation of monocyte-derived macrophages as key effectors involved in diet-induced HCC development. RT-qPCR analyses of hepatic tissue evidenced a diet-independent downregulatory effect of SETIs on the transcripts of CD36, FASN, ALOX15, and SREBP1c; however, animals fed with an STD showed opposing effects for PPAR and NRLP3 levels. These effects were accompanied by a decreased production of IL-6 and IL-17 but increased that of TNF in animals receiving SETIs. Moreover, only animals fed an HFD displayed increased concentrations of the stem cell factor. Overall, SETIs administration decreased the hepatic contents of lysophosphatydilcholine, phosphatidylinositol, phosphatidylcholine, and phosphatidyl ethanolamine. Notably, animals that received SETIs exhibited increased hepatic proportions of CD68+CX3CR1+CD74+ cells and at a higher rate in those animals fed an HFD. Altogether, the data evidence that oral administration of SETIs modulates the tumor microenvironment, improving hepatic innate immune response(s) and favoring a better antitumoral environment. It represents a path forward in developing coadjutant strategies to pharmacological therapies, with either a preventive or therapeutic character, to counter physiopathological conditions at early stages of HCC development.

Immunonutritional Bioactives from Chenopodium quinoa and Salvia hispanica L. Flour Positively Modulate Insulin Resistance and Preserve Alterations in Peripheral Myeloid Population.

Innate immunity plays a determinant role in high fat diet (HFD)-induced insulin resistance. This study compares the effects of immunonutritional bioactives from Chenopodium quinoa (WQ) or Salvia hispanica L. (Ch) when used to partially replace wheat flour (WB) into bread formulations. These flours were chosen to condition starch and lipid content in the products as well as because their immunonutritional activity. To be administered with different bread formulations, HFD-fed C57BL/6J mice were distributed in different groups: (i) wild type, (ii) displaying inherited disturbances in glucose homeostasis, and (iii) displaying dietary iron-mediated impairment of the innate immune TLR4/TRAM/TRIF pathway. We analyze the effects of the products on glycaemia and insulin resistance (HOMA-IR), plasmatic triglycerides, intestinal and hepatic gene expression and variations of myeloid (MY), and lymphoid (LY) cells population in peripheral blood. Our results show that feeding animals with WQ and Ch formulations influenced the expression of lipogenic and coronary risk markers, thus attaining a better control of hepatic lipid accumulation. WQ and Ch products also improved glucose homeostasis compared to WB, normalizing the HOMA-IR in animals with an altered glucose and lipid metabolism. These positive effects were associated with positive variations in the peripheral myeloid cells population.

Studying the Impact of Different Field Environmental Conditions on Seed Quality of Quinoa: The Case of Three Different Years Changing Seed Nutritional Traits in Southern Europe.

Chenopodium quinoa Willd (quinoa) has acquired an increased agronomical and nutritional relevance due to the capacity of adaptation to different environments and the exceptional nutritional properties of their seeds. These include high mineral and protein contents, a balanced amino acid composition, an elevated antioxidant capacity related to the high phenol content, and the absence of gluten. Although it is known that these properties can be determined by the environment, limited efforts have been made to determine the exact changes occurring at a nutritional level under changing environmental conditions in this crop. To shed light on this, this study aimed at characterizing variations in nutritional-related parameters associated with the year of cultivation and different genotypes. Various nutritional and physiological traits were analyzed in seeds of different quinoa cultivars grown in the field during three consecutive years. We found differences among cultivars for most of the nutritional parameters analyzed. It was observed that the year of cultivation was a determinant factor in every parameter studied, being 2018 the year with lower yields, germination rates, and antioxidant capacity, but higher seed weights and seed protein contents. Overall, this work will greatly contribute to increase our knowledge of the impact of the environment and genotype on the nutritional properties of quinoa seeds, especially in areas that share climatic conditions to Southern Europe.

Combined Effect of Chia, Quinoa and Amaranth Incorporation on the Physico-Chemical, Nutritional and Functional Quality of Fresh Bread.

With regard to constant technological innovations in the bakery sector in order to increase bread nutritional value without affecting its technological and sensory characteristics, we applied pseudocereals/oilseeds to obtain an optimal formulation. A factorial design 33 was used and the independent factors were chia flour (levels: 0, 10, 20% flour basis), quinoa flour (levels: 0, 20, 40% flour basis), and amaranth flour (levels: 0, 20, 40% flour basis). Their effects and interactions were studied through the response surface methodology to optimise the bread formulation from a holistic viewpoint, which included the nutritional, technological and sensory characteristics. The optimum formulation with the highest quality was the blend made with 10, 4, and 20% of chia, quinoa, and amaranth, respectively. The results showed a significant increase in protein amount, ash, lipids, and crumb firmness compared to wheat bread. The calorie value of the control sample and the optimised formula were significantly similar, bearing in mind the high lipid amounts present in raw materials. Loaf-specific volume slightly decreased in comparison to control bread, as expected in formulations with gluten-free raw materials and a large amount of fibre. The optimised formula presented nutritionally/functionally higher indexes and similar overall acceptability to the control bread (p < 0.05).

Kinetic Approach to the Influence of Chia Flour on Glucose Bioaccessibility from Hydrothermally Treated Maize and Quinoa Starch.

Starch structure and bioactive ingredients play an implicit role in the control of glucose release at intestinal level reducing the risk of inadequate metabolic response(s). This study performs a comparative kinetic approach to glucose release from hydrothermally treated (HT) maize (MS) and quinoa (QS) starch. Besides, chia flour (CF) (20%, w/w) was added to evaluate its influence of on the apparent diffusion coefficients (Dapp) when subjected to simulated gastrointestinal digestion. Hepatocyte cultures were used to monitor mitochondrial enzymes activity (test MTT) to bioaccessible glucose concentrations. With an increasing temperature, Dapp for both QS and its mixtures with CF were kept unaltered, while those for MS were disrupted progressively affecting glucose bioaccessibility. Principal component analysis revealed differences between maize and quinoa starches, but common features in the corresponding mixtures with CF. Data indicated that quinoa starch helps controlling glucose release and that addition of CF decreased mitochondrial activity in presence of insulin.

Inclusion of Salvia hispanica L. and Chenopodium quinoa into bread formulations improves metabolic imbalances derived from a high-fat intake in hyperglycaemic mice.

High-energy intake causes imbalances in nutrient homeostasis contributing to a high prevalence of metabolic chronic diseases. The extent to what metabolic imbalances can be ameliorated by the inclusion of immunonutritional ingredients obtained from flours favouring nutrient and calorie management remains poorly understood. Herein, it is demonstrated that partial replacement of wheat flour (WB) with that from Chenopodium quinoa varieties [red (RQ, 25% w/w) and white (WQ, 25% w/w)] as well as from Salvia hispanica L., [whole (Ch, 20% w/w) and semi-defatted (Ch_D, 20% w/w)] in bread formulations ameliorates the metabolic and inflammation consequences of high-fat diet consumption in hyperglycaemic animals. Feeding animals with bread formulations replacing wheat flour effectively reduced insulin resistance (by 2-fold, HOMAir). The reduction in starch content did not appear as a determinant of controlling HOMAir. Only animals fed with RQ and Ch diet displayed increased plasma levels of triglycerides, which significantly contributed to mitigate HFD-induced hepatic lipid peroxidation. The latter was increased in animals receiving Ch_D diet, where PUFAs were eliminated from chia's flour. Feeding with WQ and Ch samples caused an upward trend in hepatic TNF-α and IL-6 levels. Despite similarities between immunonutritional agonists in animals fed with RQ and WQ, IL-17 levels were quantified higher for animals fed with WQ. All bread formulations except Ch_D samples significantly increased the hepatic granulocyte-monocyte colony stimulation factor levels. These results indicated that replacement of wheat flour with that from quinoa and chia improved the metabolic imbalances in hyperglycaemic animals.

Assessment of the glycaemic index, content of bioactive compounds, and their in vitro bioaccessibility in oat-buckwheat breads.

This study addressed determinations of the glycaemic index (GI), antioxidant capacity (AC), and phenolics content (TPC) of oat, buckwheat, and mixed oat/buckwheat breads. The bioaccessibility of TPC and the AC of breads were studied after in vitro digestion. The lowest values of the GI were determined for oat bread, whereas breads with the highest content of buckwheat flour had the highest AC. The digestion of breads showed that most of the TPC were found in the soluble fraction, but the phenolic compounds were still present also in the insoluble fraction after digestion. It was concluded that the mixed oat-buckwheat breads may serve as products with a medium GI, as a source of TPC, and as products with a high AC. It should be noted that enzymatic digestion or fermentation by microbiota could potentially enhanced breads antioxidant activity during digestion in the gastrointestinal tract.

Development of Highly Nutritional Breads with By-Products of Chia (Salvia hispanica L.) Seeds.

The effect of the incorporation of various types of residual chia flour (whole, semi-defatted and defatted, with or without mucilage) on the technological quality of bread was investigated. The various types of chia flour were used to substitute 5 and 10% wt/wt of wheat flour in the bread formulations. The water absorption, dough development time and stability of blends with the presence of mucilage and the incorporation of 10% wt/wt of chia flour demonstrated the highest values in comparison with the other ones. The specific volume of the flour variants with 5% wt/wt of chia flour with mucilage were similar to the control bread; while those formulated with chia flour without mucilage exhibited a lesser volume. The incorporation of 10% wt/wt of chia flour in the formulations caused a decrease in the technological quality of the bread as expected. The bread crust and crumb colour parameters were mainly influenced by the level of chia flour substitution, which resulted in a decrease in lightness and h values. The substitution of wheat flour with 5% wt/wt of chia flour counterparts with mucilage improved the technological quality of the breads. The different oil content of the chia flours did not show any significant influence on overall quality or texture.

Combined Effect of Chia Flour and Soy Lecithin Incorporation on Nutritional and Technological Quality of Fresh Bread and during Staling.

The objectives of the present investigation are to study the interaction and optimize the blend composition of flour of grinded Chia seeds, combined to Soy lecithin, a bread making improver, in a way to enhance the nutritional/functional value of bread without impairing its technological quality and to delay its staling rate. Nine formulations were prepared following a Central Composite Design. Technological attributes were evaluated both for fresh and stored bread. In the Response Surface Methodology (RSM) a desirability function identified the optimum doses of chia and lecithin incorporation to obtain the highest specific volume and the lowest crumb firmness. Compared to the control, samples with chia and lecithin significantly increased the nutritional value of bread. An innovative and interesting synergy was found in lecithin/chia combination to enhance the specific volume, to reduce the initial crumb firmness and to delay bread staling by retarding crumb firmness and reducing its water loss during storage. Using the RSM, the optimum blend containing (4.04%-Chia/1%-Lecithin) showed fresh bread with maximum specific volume and minimum crumb firmness. Whereas, bread combining the optimum blend (3.43%-Chia/1%-Lecithin) and stored for two days at room temperature showed the minimum crumb firmness.

C. quinoa and S. hispanica L. Seeds Provide Immunonutritional Agonists to Selectively Polarize Macrophages.

Diet-related immunometabolic-based diseases are associated with chronic inflammation in metabolic tissues, and infiltrated macrophages have been suggested as mediators for tissue- damaging inflammation. Growing evidence implicates Chenopodium quinoa and Salvia hispanica L. as important contributors to immunonutritional health. However, the functional roles of the immunonutritional protease inhibitors (PPIs) found in these crops on the macrophages' metabolic and phenotypic adaptation remain to be elucidated. The salt soluble fraction of proteins was extracted and analyzed confirming the presence of 11S and 2S albumin. The <30 kDa fraction of the extract from both crops was subjected to simulated gastrointestinal digestion, where (RP-LC-MS/MS analyses) polypeptides from 2S-type of proteins were found, along with the 2S albumin (13 kDa) for S. hispanica in the bioaccessible fraction (BAF). Using human-like macrophage cells to deepen our understanding of the modulatory effects of this BAF, FACS analyses revealed their potential as TLR4 agonists, favoring increased phenotypic CD68/CD206 ratios. The results of mitochondrial stress tests showed that cells increased oxygen consumption rates and non-mitochondrial respiration, confirming negligible deleterious effects on mitochondrial function. At molecular-level, adaptation responses shed light on changes showing biological correlation with TLR4 signaling. The resulting immunometabolic effects triggered by PPIs can be a part of a tailored nutritional intervention strategy in immunometabolic-based diseases.

Effects of Black Quinoa Wet-Milling Coproducts on the Quality Properties of Bologna-Type Sausages During Cold Storage.

The incorporation of a new ingredient into foods could not only affect the intrinsic properties of the product but also its shelf life. The aim of this study was to investigate the effect of the black quinoa (both as whole seeds and as the fibre-rich fraction obtained as coproduct from its wet-milling process) on the shelf life of Bologna-type sausages during cold storage. Three treatments of Bologna-type sausages were produced: control, sausages with black quinoa seeds (2.5%), and sausages with their fibre-rich fraction (2.5%). The effect of the black quinoa added on the physicochemical properties (pH and colour), lipid oxidation, residual nitrite level, and microbiological quality of Bolognas during 21 days of cold storage was evaluated. Although the addition of quinoa products in Bologna-type sausages modified some colour parameters (day 0), these differences were masked through the storage period. Sausages with quinoa products added showing lipid oxidation values lower than the control for all the days studied. Sausages with quinoa products added showed higher residual nitrite levels than control at all measurement times during the storage period. The addition of black quinoa did not affect microbial stability during storage. Black quinoa products can be considered promising ingredients to be used as antioxidants and natural nitrate sources in Bologna-type sausages without affecting their microbial safety during storage.

Development of Healthy, Nutritious Bakery Products by Incorporation of Quinoa.

The use of quinoa could be a strategy for the nutritional improvement of bakery products. The inclusion of this pseudocereal, with its suitable balance of carbohydrates, proteins, lipids and minerals, could contribute to attaining the adequate intake values proposed by the FAO (Food and Agriculture Organization) and/or EFSA (European Food Safety Authority) for suitable maintenance and improvement of the population's health. Bakery products made with white, red or black royal quinoa significantly improved the contribution to an adequate intake of polyunsaturated fatty acids (linoleic and linolenic acids) and dietary fibre, which produced an improvement in the soluble/insoluble fibre ratio. There was also an increase in the contribution to the average requirement of Fe and Zn, although the increase in the phytate/mineral ratio would make absorption of them more difficult. Inclusion of flour obtained from the three quinoas studied slightly improved the protein quality of the products that were prepared and positively affected the reduction in their glycaemic index.

Effect of Incorporating White, Red or Black Quinoa Flours on Free and Bound Polyphenol Content, Antioxidant Activity and Colour of Bread.

Interest in quinoa as a functional food ingredient is currently emerging. The flours from white, red and black quinoa seeds were analysed in terms of total polyphenol content and antioxidant activity. They were incorporated at 25% on flour basis into the bread dough formula to evaluate their potential to improve the functional properties of wheat breads. The contribution of extractable polyphenols (soluble forms) and the largely unexplored hydrolysable polyphenols (bound forms that can be found in the residues of the former) were taken into account to reflect a realistic health-promoting potential of breads. The red and black quinoa varieties stood out compared to wheat flour, with about double the polyphenol content and up to 4.7-fold increments in antioxidant activity when considering the sum of extractable and hydrolysable polyphenols. The red and black flours were equally effective in intensifying the antioxidant properties of bread despite the baking process (between 2- and 3-fold). They produced significant changes in the parameters that describe crust and crumb colour (L*, a*, b*). A clear darkening was observed compared to the control bread, an appealing attribute for lovers of unconventional and natural products. According to our results, the flours from the coloured quinoa seeds could be considered interesting antioxidant sources and be applied as natural ingredients in bread-making; new, promising and valuable unconventional products for consumers and producers could be developed.