New strategies to address world food security and elimination of malnutrition: future role of coarse cereals in human health

As we face increasing challenges of world food security and malnutrition, coarse cereals are coming into favor as an important supplement to human staple foods due to their high nutritional value. In addition, their functional components, such as flavonoids and polyphenols, make them an important food source for healthy diets. However, we lack a systematic understanding of the importance of coarse cereals for world food security and nutritional goals. This review summarizes the worldwide cultivation and distribution of coarse cereals, indicating that the global area for coarse cereal cultivation is steadily increasing. This paper also focuses on the special adaptive mechanisms of coarse cereals to drought and discusses the strategies to improve coarse cereal crop yields from the perspective of agricultural production systems. The future possibilities, challenges, and opportunities for coarse cereal production are summarized in the face of food security challenges, and new ideas for world coarse cereal production are suggested.

Acceptance of New Formulations of Extruded Gluten Free Snacks Based on Pulse Flours by Spanish Millennial Consumers

Nowadays, the food industry has developed novel gluten free extruded snack type products made from pulses, which could be good candidates to promote pulse consumption as a sustainable food product, while also satisfying the consumer’s demand. Snack type products are a large part of the young people’s diets and impact health outcomes, so it is essential to offer them snacks with a better nutritional profile. In this study, 81 Spanish millennial consumers tasted “in situ” six different gluten free snacks based on pulse flour (lentil and chickpea) marketed in Spain. The aim of the present study was: (a) to evaluate the Spanish millennial consumers’ acceptance level of new pulse snack type products; (b) to evaluate the segmentation of the millennial consumers and understand the difference between the segments; (c) to evaluate the potential relationship between their nutrition food labelling and consumers’ acceptance. In general, the lentil formulations (with more protein, more fat and less fiber) obtained higher scores than those of the chickpea. In addition, a multidimensional statistical analysis, preference mapping, and a statistical analysis of agglomerative hierarchical clustering were performed. Consumers were grouped into three clusters based on their preferences, allowing a detailed study of consumer acceptance of the selected snacks. Cluster 1 like less the samples with less salt, and, on the contrary, these samples were preferred by Cluster 3. Cluster 2 is a group who like lentil snacks, regardless of their flavoring. It was observed that the consumer segments differ at least in their preference for saltiness. The findings of this study also showed that the nutritional composition of the analyzed snacks (as appears in nutrition labelling) was associated with Spanish millennial consumers’ acceptance and could provide valuable information to develop new snacks targeted at specific market niches, such as millennials. These data provide valuable insights when trying to anticipate Spanish millennial consumer acceptance of new gluten free pulse snacks.

Extrusion Cooking Effect on Carbohydrate Fraction in Novel Gluten-Free Flours Based on Chickpea and Rice

Extrusion cooking allows the development of value-added products from pulses, such as gluten-free snacks with added functional properties. The main objective of this study was to evaluate the changes induced by the extrusion process on the carbohydrate fraction (total carbohydrates, soluble sugars and oligosaccharides, dietary fiber, and arabinoxylans) of novel flour formulations based on chickpeas and rice enriched with different dietary fiber sources. Moreover, the influence of the addition of fiber-rich ingredients, such as Fibersol^® and passion fruit, on the analyzed compounds was also evaluated. Sucrose was the main soluble sugar found in analyzed formulations, and raffinose was the prevalent oligosaccharide, followed by stachyose. The content of total α-galactosides tended to be higher after extrusion cooking. As a consequence of the extrusion treatment, the content of total and soluble dietary fiber was statistically increased in most of the analyzed samples. In general, no significant changes were observed in total arabinoxylan content as a consequence of the extrusion process, while the content of water-soluble arabinoxylans was significantly increased in extruded formulations. It was observed that the content of total available carbohydrates, stachyose, and water-soluble arabinoxylans were significantly influenced by the addition of passion fruit, Fibersol^®, and both. The incorporation of these ingredients in gluten-free formulations based on chickpeas and rice allows one to obtain suitable functional formulations for the development of innovative, gluten-free, extruded snack-type products, which could be an interesting alternative for people with celiac disease.

Pulse-Cereal Blend Extrusion for Improving the Antioxidant Properties of a Gluten-Free Flour

Extrusion is an interesting technological tool that facilitates pulse formulation into flour mixtures, with tailored fibre content, total antioxidant capacity (TAC) and glycemic index (GI) among other components in final formulas. The gluten-free (GF) market has significantly grown during the last years. GF products have evolved from specialty health foods to products targeted to the general population and not only associated to celiac consumers. This study evaluates how temperature, cereal base (rice/corn) and pulse concentration affect extruded flour properties and which conditions are more efficient to develop a gluten-free flour with high TAC and low GI. Additionally, it evaluated the effect of this optimal formula after the baking process. The results showed an increase of total phenol (TP) and antioxidant activity with extrusion, with a temperature-dependent effect (130 °C ≥ 120 °C ≥ 110 °C), which may imply an enhanced bioaccessibility of phenolics compounds after extraction. Extrusion increased GI in comparison to native flour; however, a dough temperature of 130 °C resulted in a significantly (p ≤ 0.05) lower GI than that observed for 110-120 °C doughs, probably associated to the pastification that occurred at higher temperatures, which would decrease the degree of gelatinization of the starches and therefore a significant (p ≤ 0.05) GI reduction. Corn-lentil flour showed higher antioxidant properties and lower GI index in comparison with rice-lentil blends. The formulation of the optimal blend flour into a baked product (muffin) resulted in a significant loss of antioxidant properties, with the exception of the reducing power (FRAP), although the final antioxidant values of the baked product were in the range of the original native flour blend before any process.

Changes in Phenolics during Cooking Extrusion: A Review

In this paper, significant attention is paid to the retention of phenolics in extrudates and their health effects. Due to the large number of recent articles devoted to total phenolic content (TPC) of input mixtures and extrudates, the technological changes are only presented for basic raw materials and the originating extrudates, and only the composites identified has having the highest amounts of TPC are referred to. The paper is also devoted to the changes in individual phenolics during extrusion (phenolic acids, flavonoids, flavonols, proanthocyanidins, flavanones, flavones, isoflavons, and 3-deoxyanthocyanidins). These changes are related to the choice or raw materials, the configuration of the extruder, and the setting the technological parameters. The results found in this study, presented in the form of tables, also indicate whether a single-screw or twin-screw extruder was used for the experiments. To design an extrusion process, other physico-chemical changes in the input material must also be taken into account, such as gelatinization of starch; denaturation of protein and formation of starch, lipids, and protein complexes; formation of soluble dietary fiber; destruction of antinutritional factors and contaminating microorganisms; and lipid oxidation reduction. The chemical changes also include starch depolymerization, the Maillard reaction, and decomposition of vitamins.

Pulse-based snacks as functional foods: Processing challenges and biological potential

Despite their high nutritional value and potential health benefits, pulse intake has not increased in the last three decades. Several strategies have been implemented to increase pulse consumption, such as their incorporation in bakery products, breakfast cereals, and snacks. The inclusion of pulses in these products could be an alternative to satisfy the consumers' demand for healthy foods. However, pulse-based snacks face important challenges, including reducing antinutritional factors, achieving consumer acceptance, and consolidating the pulse-based snacks as functional foods. This review summarizes and discusses methods for producing snacks where cereals or tubers were replaced with at least 50% pulses. Also, it briefly assesses their effect on nutritional composition, antinutritional factors, sensory acceptance, and different health benefits evaluations. Extruded snacks exhibited high protein and dietary fiber and low fat content, contrary to the high fat content of deep fat-fried snacks. Meanwhile, baked snacks presented moderate concentrations of protein, dietary fiber, and lipids. Pulses must be pretreated using process combinations such as soaking, dehulling, cooking, fermentation, germination, and extrusion to reduce the antinutritional factors. Pulse-based snacks show good sensory acceptance. However, sensory evaluation should be more rigorous using additional untrained judges. Several studies have evaluated the health benefits of pulse-based snacks. More research is needed to validate scientifically the health benefits associated with their consumption. Pulse-based snacks could be an alternative to improve the nutritional composition of commercially available snacks. The use of pulses as ingredients of healthier snacks represents an important alternative for the food industry due to their low cost, sensory characteristics, high nutritional profile, and environmental benefits.

Pasta from yellow lentils: How process affects starch features and pasta quality

The effects of conventional extrusion (CV) and extrusion-cooking (EC) were investigated on 100% yellow lentils (YL). Both the extrusion processes led to pasta with good cooking quality (cooking loss: 7.0-7.1 g/100 g, firmness: 530-608 N), even in overcooking (cooking loss: 7.7-7.9 g/100 g, firmness: 418-513 N). Contrary to what is known for gluten-free cereals, CV is effective in producing pasta from native YL with no need for a pre-gelatinization step. However, pasta from EC showed a higher compression energy (2898 versus 2448 N*mm). In this sample, starch presented a higher degree of gelatinization (75.5 versus 57.6 g/100 g) and lower enthalpy (0.97 versus 1.07 J/g). At the same time, EC promoted a more compact structure that required higher temperature for melting (66.49 versus 63.16 °C) and showing pasting properties (79.1 versus 74.7 °C). Thus, by selecting suitable extrusion conditions it is possible to improve the cooking behavior of 100% pulse pasta.

Extruded coffee parchment shows enhanced antioxidant, hypoglycaemic, and hypolipidemic properties by releasing phenolic compounds from the fibre matrix

The dietary fibre and phenolic contents and the functional properties of extruded coffee parchment flour were studied to evaluate its possible use as an ingredient rich in dietary fibre (DF) with potential antioxidant, hypoglycaemic and hypolipidemic properties in extruded products. Coffee parchment flour treated at 160-175 °C and 25% moisture feed showed higher DF (84.3%) and phenolic contents (6.5 mg GAE per g) and antioxidant capacity (32.2 mg TE per g). The extrusion process favoured the release of phenolic compounds from the fibre matrix. Phytochemicals liberated during in vitro simulated digestion exhibited enhanced antioxidant capacity and attenuated reactive oxygen species in intestinal cells (IEC-6). However, the physicochemical and techno-functional properties were just affected by extrusion at high temperature, although extruded coffee parchment flours exhibited lower bulk density and higher swelling capacity than non-extruded ones. Extruded coffee parchment preserved the glucose adsorption capacity and enhanced the α-amylase in vitro inhibitory capacity (up to 81%). Moreover, extruded coffee parchment maintained the ability to delay glucose diffusion and exhibited improved capacity to retard starch digestion in the gastrointestinal tract. The extrusion of coffee parchment flours preserved the cholesterol-binding ability and augmented the capacity of this ingredient to bind bile salts, favouring the inhibition of pancreatic lipase by coffee parchment. These discoveries generate knowledge of the valorisation of coffee parchment as a food dietary fibre ingredient with antioxidant, hypoglycaemic, and hypolipidemic properties that are enhanced by the release of phenolic compounds from the fibre matrix through the production of extruded products.

Extrusion Process as an Alternative to Improve Pulses Products Consumption. A Review

The development of new food products obtained by extrusion processing has increased in recent years. Extrusion is used by the food industry to produce a wide variety of food products, such as ready-to-eat foods (e.g., snacks), among others. Pulses have also gained popularity as novel food ingredients in the formulation of a variety of food and food products, due to their high content of macro and micronutrients, and bioactive compounds that improve the nutritional and functional properties of the final food products. In this review, the impact of extrusion variables on proteins, carbohydrates, vitamins, phenolics and antinutritional compounds in pulses and pulse-based formulations are highlighted. Particularly, the impact of the specific mechanical energy. Also, the preservation, increase and/or reduction in those functional compounds, as a consequence of different extrusion processing conditions, are discussed.

Autoclaved and Extruded Legumes as a Source of Bioactive Phytochemicals: A Review

Legumes have been consumed since ancient times all over the world due to their easy cultivation and availability as a low-cost food. Nowadays, it is well known that pulses are also a good source of bioactive phytochemicals that play an important role in the health and well-being of humans. Pulses are mainly consumed after processing to soften cotyledons and to improve their nutritive and sensorial characteristics. However, processing affects not only their nutritive constituents, but also their bioactive compounds. The final content of phytochemicals depends on the pulse type and variety, the processing method and their parameters (mainly temperature and time), the food matrix structure and the chemical nature of each phytochemical. This review focuses on the changes produced in the bioactive-compound content of pulses processed by a traditional processing method like cooking (with or without pressure) or by an industrial processing technique like extrusion, which is widely used in the food industry to develop new food products with pulse flours as ingredients. In particular, the effect of processing methods on inositol phosphates, galactosides, protease inhibitors and phenolic-compound content is highlighted in order to ascertain their content in processed pulses or pulse-based products as a source of healthy phytochemicals.

Antioxidant Phytochemicals in Pulses and their Relation to Human Health: A Review

Pulses are a staple food cultivated since ancient times, which play an important role in the human diet. From a nutritional point of view, pulses are very interesting foods as they are rich in proteins, carbohydrates and dietary fibre. Dietary antioxidants are a complex mixture of hydrophilic and lipophilic compounds usually present in foods of plant origin, including pulses. In the present study, the phytochemical composition of selected pulses (common beans, fava beans, lentils, chickpeas, peas and lupins) has been reviewed in terms of their content of antioxidant compounds. The content of hydrosoluble antioxidants (organic acids, phenolic compounds), liposoluble antioxidants (tocopherols, carotenoids) and other compounds which exert antioxidant properties, such as dietary fibre and minerals (zinc, selenium), has been studied, reporting that pulses are an interesting source of these compounds, which have important health benefits, including a preventing role in cardiovascular diseases, anticarcinogenic or neuroprotective properties. It is important to take into account that pulses are not usually consumed raw, but they must be processed before consumption in order to improve their nutritional quality and their palatability, therefore, the effect of different technological and heat treatments (germination, cooking, boiling, extrusion) on the antioxidant compounds present in pulses has been also reviewed. In this regard, it has been observed that as a consequence of processing, the content of phytochemicals with antioxidant properties is usually decreased, but processed pulses maintain relevant amounts of these compounds, preserving their beneficial health effect.

Extrusion cooking of protein-based products: potentials and challenges

Extrusion cooking is receiving increasing attention as technology applied for the production of protein-based products. Researchers in this field showed that proteins from several sources are barely consumed because of their poor functionality and lack of acceptability related to the presence of some antinutritional factors. In this regard, extrusion is becoming of key importance thanks to its ability to improve protein functional properties. Based on this remarkable advantage, several studies have been published so far providing evidence of the enhanced functional, physicochemical and sensory properties of protein-based extruded products. The objective of the present review is to give a detailed overview of the potential of extrusion for the production of protein-based products. More specifically, the work describes all the studies published so far on vegetable and animal proteins including those recently released applying the technology on insect proteins. The aspects related to the functional properties of the extrudates together with the quality changes occurring during the process are also described to highlight the potential of the technology for future applications.

Potential Health Claims of Durum and Bread Wheat Flours as Functional Ingredients

Wheat is an important cereal with a key role in human nutrition. In this study, dietary fiber (DF) and arabinoxylans of different durum (Triticum turgidum ssp. Durum L.) and bread (Triticum aestivum L.) wheat flours were analyzed in order to point out their potential nutritional and health claims allege according to the current European regulation (Regulation (EU) No 432/2012). Moreover, other bioactive compounds (phenolics and tocopherols) were quantified as a first approach to their phytochemical composition in the analyzed wheat varieties. DF was analyzed following AOAC enzymatic-gravimetric methods; arabinoxylans and total phenols were quantified by colorimetric methods; tocopherols were determined by HPLC; antioxidant activity was evaluated using three different in vitro assays. Insoluble DF was the prevailing fraction in all analyzed samples. Water extractable arabinoxylans were higher in durum wheat flours. Whole flours contained higher total phenolics compounds. Alpha-tocopherol was the major isoform. Whole flours showed higher antioxidant properties. According to the obtained results, it is possible to allege all approved health claims referred to wheat, since all analyzed samples, especially whole flour and bran fraction, showed potential health benefits, as functional ingredients or functional foods, related with their phytochemical composition.

Dietary fiber sources and human benefits: The case study of cereal and pseudocereals

Dietary fiber (DF) includes the remnants of the edible part of plants and analogous carbohydrates that are resistant to digestion and absorption in the human small intestine with complete or partial fermentation in the human large intestine. DF can be classified into two main groups according to its solubility, namely insoluble dietary fiber (IDF) that mainly consists on cell wall components, including cellulose, some hemicelluloses, lignin and resistant starch, and soluble dietary fiber (SDF) that consists of non-cellulosic polysaccharides as non-digestible oligosaccharides, arabinoxylans (AX), β-glucans, some hemicelluloses, pectins, gums, mucilages and inulin. The intake of DF is associated with health benefits. IDF can contribute to the normal function of the intestinal tract and it has an important role in the prevention of colonic diverticulosis and constipation. SDF is extensively fermented by gut microbiota and it is associated with carbohydrate and lipid metabolism, with important health benefits due to its hypocholesterolemic properties. Due to these nutritional and health properties, DF is widely used as functional ingredients in food industry, being whole grain cereals, pulses, fruits and vegetables the main sources of DF. Also some synthetic sources are employed, namely polydextrose, hydroxypropyl methylcellulose or cyclodextrins. The DF content of cereals varies depending on cultivars, their botanical components (pericarp, emdosperm and germ) and the processing conditions they have undergone (baking, extrusion, etc.). In cereal grains, AX are the predominant non-cellulose DF polysaccharides followed by cellulose and β-glucans, while in pseudocereals, pectins are quantitatively predominant.

Enrichment of soybean dietary fiber and protein fortified rice grain by dry flour extrusion cooking: the physicochemical, pasting, taste, palatability, cooking and starch digestibility properties

With the prevalence of chronic conditions in patients due to a dietary imbalance, the demand for inexpensive, nutritious and high dietary fiber extruded rice is increasing rapidly. However, the factors of quality and bioavailability are still the major constraints to its development. In this study, soybean dietary fiber (DF) and protein fortified rice grain were prepared via dry flour extrusion processing. The results showed that the extruded rice had a similar density to that of natural rice and a significantly lower whiteness degree and transparency. Notably, the cooking texture and palatability of extruded rice were affected by the added amount of DF, resulting in rice with a taste value close to 70 in DF 6-9% (w/w) samples. The pasting properties, microstructure, and molecular interactions according to RVA, SEM and FTIR analyses, respectively, were also significantly affected by the DF content. The soluble dietary fiber was significantly increased from 0.0021 g g-1 to 0.216 g g-1 in extruded rice. Importantly, the starch digestibility in vitro showed significantly lower readily digestible starch (RDS) and higher resistant starch (RS) in DF 6-15% (w/w) extruded rice than in natural rice and DF-0 rice, respectively. The glycemic index (GI) was reduced in DF > 6%. In this study, we provide a new high dietary fiber extruded rice product with good texture and palatability, and we reveal the effect of DF on the extruded rice properties.