Gluten-free Cereals Research Articles

A Comprehensive Review on Quinoa

Quinoa (Chenopodium quinoa Willd) is pseudocereal that has survived in the Andean region's tough bioclimatic conditions since time immemorial. This crop is still widely grown in the Bolivian and Peruvian areas. Many countries are expressing interest currently because of its wide agro-ecological adaptability and its ability to provide food security in developing countries. Quinoa is also incredibly healthy due to its high protein content, which includes all essential amino acids, gluten-free, PUFA and mineral content, which includes calcium, magnesium, iron, sodium, and potassium, as well as flavonoids. Based on its diverse qualities, FAO declared 2013 to be the "International Year of Quinoa." Gluten free cereal grains with great amounts of nutrients and can replace wheat in various food products. Quinoa is one of those cereals which have all – in it.

Considering a more sustainable gluten-free diet? Gluten-free cereals in European dietary practice

BackgroundThe inclusion of minor and pseudo-cereals enhances the nutritional quality of a gluten-free diet. Yet, affordability determines practical implementation. Environmental concerns should also be considered as moving towards a more sustainable diet. How do these aspects of sustainability manifest themselves in a special diet, such as gluten-free?MethodsAn international pilot survey among practicing dietitians was conducted during the Congress of The European Federation of the Associations of Dietitians (EFAD, Budapest, 2023). Respondents marked their recommendation for eight gluten-free cereals based on five criteria, including nutritional quality, accessibility/price, and climate change. Differences were analysed using Cohran’s Q and pairwise post-hoc tests (N = 38).ResultsThere were significant differences in the recommendation for cereals (p < 0.05 for each grain), with quinoa (89.5%), gluten-free oats (89.5%), rice (86.8%), and corn (65.8%) being the most recommended. Buckwheat (55.3%), millet (50.0%), amaranth (44.7%) and sorghum (26.3%) were less recommended. Although gluten-free oats were recommended overall, quinoa was recommended for its nutritional content, and rice and corn were recommended for accessibility/price. No cereal received a high recommendation for climate change.ConclusionsAccording to this pilot survey, nutritional content and accessibility/price were the most important criteria for evaluating gluten-free grains. Dietitians were willing to integrate climate change considerations into practice, but more information is needed. The recommendation for minor and pseudo-cereals contradicted the importance emphasised by the literature. Further research is needed to integrate these aspects, helping dietitians formulate recommendations.

A Descriptive Study of Spanish and Ecuadorian Commercial Infant Cereals: Are They in Line with Current Recommendations?

Cereals are an important source of nutrients, especially used in complementary feeding. The objective of this study is to review the nutritional composition of cereal-based foods for infants from 4 months and toddlers that are offered in Spain and Ecuador, countries selected because of the opportunity to work in them, and due to their socio-economic differences (industrialized and developing countries, respectively). The number of these products was 105 cereals in Spain and 22 in Ecuador. The products were classified as gluten-free cereals, five cereals, eight cereals, multigrain cereals, and cookies. A 25 g serving was used to determine the percentage in which the samples analyzed can cover the Reference Nutrient Intake (RNI) for micronutrients in infants from 7 months and toddlers according to the European Food Safety Authority (EFSA). Nutritional information per 100 g of dry product was collected according to medium, minimum, and maximum units, and nutrient density was calculated. The age range in which these products are recommended is different in both countries. The nutritional composition presents some differences; Spanish cereals show a lower content of sodium, added sugars, hydrolyzed cereals, and maltodextrin than Ecuadorian cereals. Commercialized cereals could contribute to satisfying the nutritional needs of infants and toddlers; however, they can also be a source of non-recommended components.

Impact of Cactus Mucilage Powder as New Natural Hydrocolloid on Physicochemical, Staling Rate and Sensory Characteristics of Gluten-free Egyptian Flat Bread

The growing market for gluten-free (GF) products has encouraged the development of several GF bakery products that aim to mimic the high standards of wheat bakery goods. The objective of this study was to investigate the impact of cactus mucilage powder (CMP) as new natural hydrocolloid on the characteristics of GF flat bread. Wheat flour was replaced by rice flour (RF) as a GF cereal. Different levels of Xanthan gum (XG), CMP or their combination between them were used to investigate their impact on physicochemical properties, alkaline water retention capacity (AWRC), staling rate (SR) and sensory characteristics of the resultant GF flat bread. Results showed that addition of XG or CMP, as natural hydrocolloids, resulted in significant increases in flat bread moisture (P ˂ 0.05). In addition, the crust color of GF flat bread was significantly lighter (L* value) than the control. Increases in AWRC were noticed as a result of XG and CMP addition. On the other hand, low concentrations of XG led to decrease in the staling rate while high concentrations resulted in slight increase in the staling rate. Addition of CMP into flat bread formulas resulted in increases in the staling rate of the investigated samples. Combination of XG with CMP led to reduction in the staling rate of flat bread comparing with CMP only. Furthermore, the ability of different formulae to retain alkaline water decreased as the storage period was increased. All gluten-free formulae containing hydrocolloids received significantly higher (P ˂ 0.05) sensory scores compared to the control.

Nutritional Traits, Pasting Properties and Antioxidant Profile of Selected Genotypes of Sorghum, Oat and Maize Eligible for Gluten-Free Products.

The technological and nutritional traits of food-grade sorghum hybrids, hulled/naked oat varieties and maize genotypes of different colors were studied for novel and healthier gluten-free foods. Oat genotypes showed the highest protein content, followed by maize and sorghum. The total starch and the total dietary fiber content were quite similar among the three species. Great variation was found in the amylose content, and the highest was in sorghum (27.12%), followed by oat 16.71% and maize 10.59%. Regarding the pasting profile, the rank of Peak Viscosity was sorghum (742.8 Brabender Unit, BU), followed by maize (729.3 BU) and oat (685.9 BU). Oat and sorghum genotypes had similar average breakdown (407.7 and 419.9 BU, respectively) and setback (690.7 and 682.1 BU, respectively), whereas maize showed lower values for both parameters (384.1 BU and 616.2 BU, respectively). The total antioxidant capacity, only in maize, significantly correlated with total flavonoid, phenolic and proanthocyanidin contents, indicating that all the measured compounds contributed to antioxidant capacity. The study indicated the importance of sounding out the nutritional and technological characteristics of gluten-free cereals in order to select suitable cultivars to be processed in different gluten-free foods with better and healthier quality.

Assessment of Sourdough Fermentation Impact on the Antioxidant and Anti-Inflammatory Potential of Pearl Millet from Burkina Faso.

Millet, a gluten-free cereal, has received attention for its environmental friendliness and higher protein content than other grains. It represents a staple food in many African countries, where fermentation is traditionally used for preserving food products and preparing different cereal-based products. This study aimed to assess the impact of sourdough fermentation on bioactive compounds and antioxidant and anti-inflammatory properties of pearl millet from Burkina Faso. Phenolic compounds were investigated spectrophotometrically and by HPLC-DAD. The antioxidant activity of unfermented (MF) and fermented (FeMF) millet was evaluated in vitro by spectrophotometric and fluorometric assays and ex vivo on oxidized human erythrocytes for hemolysis inhibition. Finally, the potential anti-inflammatory effect of FeMF and MF was evaluated on human adenocarcinoma cell line (HT-29) exposed to TNF-α inflammatory stimulus. Results revealed significantly higher levels of polyphenols, flavonoids, and in vitro antioxidant activity following millet fermentation. Notable differences in phenolic composition between FeMF and MF are observed, with fermentation facilitating the release of bioactive compounds such as gallic acid, quercetin, and rutin. A dose-dependent protection against oxidative hemolysis was observed in both FeMF- and MF-pretreated erythrocytes. Similarly, pretreatment with FeMF significantly reduced the levels of inflammatory markers in TNF-α-treated cells, with effects comparable to those of MF. Fermentation with sourdough represents a simple and low-cost method to improve the bioactive compounds content and in vitro antioxidant activity of millet flour with promising nutraceutical potential.

Discrimination of the geographical origin of gluten-free teff grains from northwestern parts of Ethiopia by fatty acid analysis

Teff (Eragrostis tef) is a gluten-free cereal, and the consumer also prefers teff due to its nutritional composition. Determining the geographical origin of teff is important to select the right product for consumers. The quality and consumer preference of teff varies based on their production origin; consequently, their prices differ significantly. This work studied the profile of fatty acids in seventy-two teff samples by using gas chromatography coupled with mass spectrometry (GC-MS) and identifying the markers to discriminate the geographical origin of teff depending on their production region. Principal component analysis (PCA) and linear discriminat Analysis (LDA) were used to visualize data trends, and construct classification models for teff samples according to their geographical origins. Thirty different fatty acids were detected in all of the collected teff samples. The total mean concentration of fatty acids ranged from 739.85 to 938.06 mg/100g across the six districts in the three zones (East Gojjam,Awi, and West Gojjam). Stearic acid,trans-vaccenic acid, linoleic acid, azelaic acid, and capric acid were the most discriminating fatty acids of teff grains between East Gojjam and West Gojjam zones, while palmitic, palmitoleic, and oleic acid discriminated Awi zone teff samples from the other zones. The recognition and prediction abilities of the LDA model for the classification of the production zones were 98.6 % and 94.4 %, respectively. Hence, the fatty acid profiles combined with multivariate data analysis too can be used in the determination of the geographical origin of teff grains.

Impact of lipids on the functional, rheological, pasting and thermal properties of ultrasound-processed canary seed flours

Canary seed, a gluten-free cereal, is renowned for its high content of fats, starch, and proteins. The extraction of oil is often necessary to extend flour shelf life or obtain purified starch and protein fractions. Similar to many gluten-free flours, it may require additional thermal treatments to enhance its suitability to formulate several food products. Thus, this study investigated the impact of ultrasound (US) treatment on the techno-functional and physicochemical properties of both whole (WCS) and defatted (DWCS) canary seed flours. The US treatment slightly increased water and oil absorption capacities in WCS. Lipids in the flour and treatment temperature affected the surfactant properties. Untreated and treated defatted DWCS flours exhibited higher emulsifying activity (up to +36%) and foaming capacity (up to +340%) than WCS. The presence of lipids and US treatment influenced protein extraction, with changes in albumins (WCS and DWCS), globulins (DWCS) and prolamins (WCS) recovery. US treatment altered pasting and rheological properties of all studied flours, impacting viscosity and starch-lipid complex formation. Rheological properties were lipid-dependent, and defatted samples formed stronger gels. US treatment decreased gelatinization enthalpy in WCS (up to −9.5%) and increased it in DWCS (up to +11.3%) flours. Moreover, lipids significantly influenced retrogradation, which was absent in untreated and treated WCS flours. US-treated flours displayed similar diffraction patterns to untreated samples, but with reduced intensities as temperature increased. The untreated defatted sample exhibited a 9% lower crystallinity. These findings highlight the benefits of US treatment and defatting for improving gluten-free food products formulated with canary seed flour.

Chemical Composition, Health Benefits and Future Prospects of Hairless Canary Seed (Phalaris canariensis L.): A Review.

The increasing global population and the rise of health-conscious consumers have led to a growing demand for innovative foods and functional ingredients. Hairless canary seed (Phalaris canariensis L.), which has recently obtained regulatory food approval from Health Canada and the United States Food and Drug Administration (US-FDA), has the potential to meet these demands due to its unique nutrient profile and characteristics. Canary seed stands out among cereals and pseudo-cereals (gluten-free cereals) as it has the highest protein content and is gluten-free. Additionally, it contains significant amounts of tryptophan, an amino acid typically lacking in cereals. It is considered a true cereal grain that can be processed into flour, starch, and oil for various food and non-food applications. This article provides a comprehensive overview of the chemical composition, functional properties, and biological activities of canary seeds. It also explores the processing methods for incorporating these seeds into food and cosmetic products. Furthermore, suggestions for future research directions are presented to enhance the utilization of this plant. Overall, it is evident that Phalaris canariensis holds considerable potential as a sustainable crop that can be further developed.

Potential Effects of the Different Matrices to Enhance the Polyphenolic Content and Antioxidant Activity in Gluten-Free Bread.

Gluten-related disorders, including celiac disease, wheat allergy, and non-celiac gluten sensitivity, have emerged as a significant phenomenon affecting people worldwide, with an estimated prevalence of nearly 5% globally. The only currently available treatment for this disease involves the exclusion of gluten from the diet, which is particularly challenging in the case of bakery products. Gluten-free bread (GFB) presents certain disadvantages when compared to traditional wheat bread, including inferior sensory attributes, technological characteristics, and lower protein and fiber content. Numerous studies have focused on strategies to improve these aspects of GFB. However, there are limited reviews regarding the content of the bioactive compounds of GFB, such as polyphenols. Polyphenols are molecules found in various foods that play a vital role in protecting the body against oxidative stress. This is particularly relevant for individuals with gluten intolerance or celiac disease, as they often experience increased oxidative stress and inflammation. Therefore, the objective of this review is to explore the use of different strategies for increasing the polyphenolic content and the antioxidant properties of GFB. Gluten-free cereals and pseudocereals are the most used matrices in GFB. Buckwheat can be a valuable matrix to enhance the nutritional profile and antioxidant properties of GFB, even more so when the whole grain is used. In the same way, the addition of various by-products can effectively increase the bioactive compounds and antioxidant activity of GFB. Furthermore, regarding the contribution of the phenolics to the bitterness, astringency, color, flavor, and odor of food, it is essential to analyze the sensory properties of these breads to ensure not only enriched in bioactive compounds, but also good consumer acceptance. In vitro studies are still in few number and are very important to execute to provide a better understanding of the bioactive compounds after their consumption.

Proteomics and Metabolomics Reveal that an Abundant α-Glucosidase Drives Sorghum Fermentability for Beer Brewing.

Sorghum (Sorghum bicolor), a grass native to Africa, is a popular alternative to barley for brewing beer. The importance of sorghum to beer brewing is increasing because it is a naturally gluten-free cereal, and climate change is expected to cause a reduction in the production of barley over the coming decades. However, there are challenges associated with the use of sorghum instead of barley in beer brewing. Here, we used proteomics and metabolomics to gain insights into the sorghum brewing process to advise processes for efficient beer production from sorghum. We found that during malting, sorghum synthesizes the amylases and proteases necessary for brewing. Proteomics revealed that mashing with sorghum malt required higher temperatures than barley malt for efficient protein solubilization. Both α- and β-amylase were considerably less abundant in sorghum wort than in barley wort, correlating with lower maltose concentrations in sorghum wort. However, metabolomics revealed higher glucose concentrations in sorghum wort than in barley wort, consistent with the presence of an abundant α-glucosidase detected by proteomics in sorghum malt. Our results indicate that sorghum can be a viable grain for industrial fermented beverage production, but that its use requires careful process optimization for efficient production of fermentable wort and high-quality beer.

Nutritional and sensory quality of Ofada rice sourdough bread made with selected lactic acid bacteria strains

Celiac disease ranks highest among immunological disorders attributed to gluten consumption thus, posing great demands on gluten-free products. Rice is a gluten-free cereal with promising dietary applications. Ofada rice, a native southwestern Nigerian variety, can be improved with sourdough technology to develop functional aglutenic bread. Ofada rice sourdough bread (ORSB) was made with Fructilactobacillus fructivorans RY1, Weissella viridescens RY9 and Lactobacillus acidophilus RY10 as individual and combined starter cultures. Physical qualities, proximate contents, sensorial attributes and shelf-life of the ORSBs were evaluated. Sourdough bread with the highest (3.10 cm3/g) and lowest specific volumes (2.02 cm3/g) were the sample made single culture of W. viridescens and F. fructivorans, respectively. The highest crude protein (8.48 %) was found in ORSB with only F. fructivorans and ORSB with L. acidophilus singly had the highest content (0.44 %) of crude fibre. Nevertheless, the least crude protein (5.25 %) and crude fibre (0.28 %) were observed in samples containing F. fructivorans, W. viridescens, and L. acidophilus as combined starters. The sourdough bread with F. fructivorans as a starter scored best for texture and overall acceptability. The ORSBs had shelf-life ranging from three to four days. It was revealed in the study that using the specific LAB starters could improve the physicochemical attributes and acceptability of bread from Ofada rice flour.

Chemical Composition, Antioxidant Potential, and Nutritional Evaluation of Cultivated Sorghum Grains: A Combined Experimental, Theoretical, and Multivariate Analysis.

Sorghum grain (Sorghum bicolor L. Moench) is a gluten-free cereal with excellent nutritional value and is a good source of antioxidants, including polyphenols, as well as minerals with proven health benefits. Herein, the phenolic composition, elemental profile, and antioxidant activity of sixteen food-grade sorghum grains (S1-S16) grown under agroecological conditions in Serbia were determined. Nine phenolic compounds characteristic of sorghum grains, such as luteolinidin, 5-methoxyluteolinidin, luteolidin derivative, luteolidin glucoside, apigeninidin, 7-methoxyapigeninidin, apigeninidin glucoside, and cyanidin derivative, were quantified. The antioxidant potential of the analyzed sorghum grains was evaluated by UV/Vis (DPPH, ABTS, and FRAP) and Electron Paramagnetic Resonance spectroscopy (hydroxyl and ascorbyl radical scavenging assays). The content of macro- and microelements was determined by Inductively Coupled Plasma Optical Emission spectroscopy. Theoretical daily intakes of selected major and trace elements were assessed and compared with the Recommended Daily Allowance or Adequate Intake. Sample S8 had the highest amount of phenolic compounds, while S4, S6, and S8 exhibited the strongest antioxidative potential. The sorghum studied could completely satisfy the daily needs of macro- (K, Mg, and P) and microelements (Se, Zn, Fe). Pattern recognition techniques confirmed the discrimination of samples based on phenolic profile and elemental analysis and recognized the main markers responsible for differences between the investigated samples. The reaction between hydroxyl radicals and luteolinidin/apigeninidin was investigated by Density Functional Theory and thermodynamically preferred mechanism was determined.

Metal(loid)s Profile of Four Traditional Ethiopian Teff Brands: Geographic Origin Discrimination.

Among the most renowned Ethiopian food crops, teff (Eragrostis tef (Zucc.)Trotter) is the most nutritious and gluten-free cereal. Because of the increase in demand for teff, it is necessary to establish geographic origin authentication of traditional teff brands based on multi-element fingerprint. For this purpose, a total of 60 teff samples were analysed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Accuracy of the laboratory procedure was verified by the analysis of rice flour standard reference material (NIST SRM 1568b). In this context, four traditional teff brands (Ada'a, Ginchi, Gojam and Tulu Bolo) were analytically characterized using multi-element fingerprint and further treated statistically using linear discriminant analysis (LDA). Due to obvious extrinsic Fe, Al and V contamination, these elements were excluded from the discriminant model. Five elements (Cu, Mo, Se, Sr, and Zn) significantly contributed to discriminate the geographical origin of white teff. On the other hand, Mn, Mo, Se and Sr were used as discriminant variables for brown teff. LDA revealed 90 and 100% correct classifications for white and brown teff, respectively. Overall, multi-element fingerprint coupled with LDA can be considered a suitable tool for geographic origin discrimination of traditional teff brands.

Changes on Techno-Functional, Thermal, Rheological, and Microstructural Properties of Tef Flours Induced by Microwave Radiation-Development of New Improved Gluten-Free Ingredients.

Tef [Eragrostis tef (Zucc.) Trotter] flour is a gluten-free cereal rich in fiber, minerals, vitamins, and antioxidants, which offers a promising alternative for new food development. This study investigated the effect of microwave radiation (MW) on the techno-functional, thermal, rheological and microstructural properties of tef flours. White and brown tef grains were milled and microwaved at different moisture contents (MC) (15%, 20% and 25%) for a total irradiation time of 480 s. The morphological structure of tef flours was affected by MW treatment, and its particle size and hydration properties increased after the treatment. Lower peak, breakdown, and setback viscosities, up to 45%, 96%, and 67% below those of the control (untreated) samples, and higher pasting temperature, up to 8 °C in the 25% MC samples, were observed. From FTIR analysis a disruption of short-range molecular order was concluded, while DSC confirmed an increased stability of starch crystallites. Rheological analysis of the gels made from the treated samples revealed that MW had a structuring and stabilizing effect on all samples, leading to higher viscoelastic moduli, G' and G″, and the maximum stress the gels withstood before breaking their structure, τmax. The MC of the flours during the MWT drove the modification of the techno-functional properties of the tef flours and the gel rheological and thermal characteristics. These results suggest that MW-treated tef flours are potential ingredients for improving the technological, nutritional and sensory quality of food products.

The Potential of Sorghum Crops In Romania, In The Context of Climate Changes

Sorghum is the fifth most cultivated cereal in the whole world, after wheat, rice, corn and barley. But this tasty and gluten-free cereal is quite little known and consumed in Romania. In Romania there are relatively few sorghum crops, although, along with amaranth, it was the basis of the Romanian diet in the 70s. It is a drought-resistant plant and much more nutritious than corn, which it resembles in many ways, sorghum can thus become a substitute for corn.

Nutritional Composition of Yellow Pericarp Sorghum (Sorghum bicolor L. Moenech): A Review

Sorghum is a gluten-free cereal and forms the staple diet of a majority of the populations living in the semi-arid tropics. It was believed that food security attained through green revolution would solve India's nutritional issues. However, we have now realized that in these attempts, rice and wheat received a lot of policy attention, while other crops such as sorghum were neglected. This trend is frequently cited as one of the causes behind nutritional conundrum in India in which undernutrition and hidden hunger coexist. Sorghum grain contains pigmented pericarp (i.e., red, yellow, brown) and non-pigmented pericarp (i.e., white). Sorghum grains with yellow pericarp have gained greater demand in market during recent times owing to its nutritional importance, good roti making quality and keeping quality. The purpose of this review paper is to provide a comprehensive understanding of yellow pericarp sorghum in terms of its nutritional composition, and to compare the nutritional characteristics with white sorghum. From a nutritional perspective, a major advantage of sorghum as a healthy and nutritious crop is its higher proportion of slowly digestible and resistant starch components compared with other staple cereal crops. The nutritional composition of Sorghum bicolor grain includes energy (193 cal), moisture content (52%), protein (7.1 g), fat (0.6 g), carbohydrates (39.8 g), fiber (0.9 g), calcium (10 mg), iron (3.5 mg), and niacin (1.7 mg). Sorghum is a good source of minerals and vitamins and mostly located in aleurone layer and germ. It is an important source of B vitamins except for vitamin B12 and vitamin A. Research studies have proven that Yellow pericarp sorghum has relatively higher protein content (12-13%) than white sorghum (10-11%) and is rich in beta carotene, leutin and zeaxanthin. It is characterized by high carbohydrate, calcium, and zinc contents. Yellow pericarp sorghum is also rich in flavanones and has slightly higher total phenolic contents than white sorghum which act as antioxidants and play a crucial role in enhancing the immune system. Thus yellow pericarp sorghum can serve as a significant nutrient-rich cereal and could play a role in dietary diversification and a balanced diet as a means of addressing nutritional security in India.

Steam Extraction System Use in the Gluten-Free Cereal Snacks Technology

When developing new types of gluten-free products, the extrusion and biocatalysis technologies use is promising. Extrusion enables to obtain ready-to-eat products of the high consumer demand with a porous structure from gluten-free cereals (snacks, ready-made breakfasts, crispbreads and various types of food concentrates), without using the functional structure-forming properties of gluten. In turn, biocatalytic technologies can provide enzymatic proline and glutamine protein bond hydrolysis of structural protein domains resistant to the digestive enzyme action. The main extrusion processing problem of wheat hydrolysates with a reduced gluten amount mixed with other raw materials is the high moisture content in the extruder. The work aimed at studying the process of additional steam extraction from the extruder cabinet during the high-moisture mixtures extrusion and its influence on the quality of finished products, i.e. gluten-free snacks. The study object was rice flour and wheat hydrolysate mixtures with a mass fermentolysate fraction of 25 and 35 %, extruded using a steam extraction system. As a result of the conducted studies, a man revealed that with an increase in steam extraction, the pressure in the extruder cabinet and the shear moment significantly increased, the process temperature slightly increased. This effect is due to the moisture content decrease in the extruder cabinet after steam extraction and, accordingly, the shear deformations energy increase. There was an additional steam extraction accompanied by an increase in specific electricity consumption by 64–79 %. The texture samples analysis demonstrated that the steam extraction and the amount of hydrolysate introduced had a significant effect on the snacks texture: the hardness decreased from 10.5 to 3.5 N, while the number of micro-fractures characterizing the crispness increased from 11.4 to 13.6. The color characteristics evaluation of the obtained snacks showed their insignificant dependence on the steam extraction. The use of a steam extraction device enables to increase the hydrolysate content in the extruded mixture and improve finished products quality during high-moisture mixtures processing.

Valorisation of resistant starch from foxtail millet for the development of gluten-free cereal bars and their quality evaluation

Valorisation of resistant starch from foxtail millet for the development of gluten-free cereal bars and their quality evaluation

Effect of sucrose on the extrusion of varied whole sorghum grits genotypes

The effect of sucrose on the extrusion of varied whole sorghum genotypes was studied using a single-screw system. The raw sorghum flours were characterized in terms of chemical composition and particle size. Specific mechanical energy (SME) was measured as a process parameter, as well as expansion properties, hydration, paste viscosity, instrumental color, and texture, along with total phenolic compounds (TPC) and total condensed tannins (TCT) in the puffed extrudates. In general, the addition of 10% sucrose reduced SME (p < .05), sectional expansion, hydration, and cold paste viscosity, indicating lower starch conversion and increased lightness (L*) and hardness (Fc). In contrast, BRS 501 showed opposite results for most of the variables measured, due to the suppression of the lubricant effect attributed to the high lipid in this genotype. Furthermore, the extrusion process at 0% sucrose released TPC values by 71.2% and 317.5% for low-tannin extrudates, while the addition of sucrose (10%) did not alter the TPC (p > .05) and had a protective effect on TCT retention in BRS 305 genotype extrudates. Practical applications The worldwide food intake of non-traditional whole grains such as sorghum has been restricted. Although it has been recently considered as an interesting an attractive gluten-free cereal due to its high and varied content of phytochemicals that provide health benefits and dietary fiber source. To take advantage of its potential, thermoplastic extrusion technology was used as a tool to develop textured sorghum expanded products with improved digestibility and retention of bioactive compounds. On the other hand, in order to improve its potential use as sweet snacks, the addition of sugar concentrations (10%) was added to improve its palatability, allowing to obtain expanded extrudates rich in fiber and bioactive compounds with improved taste compared to conventional extrudates, which would be of interest of the consumer and the food industries.