Nutrient profile and effect of processing methods on the composition and functional properties of lentils (Lens culinaris Medik): A review

Grain legumes or pulses, including lentil (Lens culinaris Medik), have gained increasing popularity among consumers and food processors in recent years. This trend has been driven by the consumers opting for plant‐based proteins and environmentally sustainable food sources. Global production of lentils has more than doubled since 2001 (from 3.15 to 6.58 million metric tons in 2020), which signifies the commercial importance of this nutrient‐dense legume. As per the USDA's nutrients data (2022), lentil contains 24.6% protein, 63.4% carbohydrates, 2.7% ash content, and 1.1% total fat. High amount of dietary fiber, slowly digestible starch and potassium, and low sodium in lentil align well with consumer choices for healthy foods. Many studies have reported on the health benefits of consuming lentils, especially being effective in reducing various health conditions, such as hypertension, cardiovascular diseases, diabetes mellitus, and cancer. The relatively higher protein and lower carbohydrates content of lentil compared with cereal grains can help in expanding the utilization of lentils and lentil‐based ingredients to develop new products. Combined with high dietary fiber, resistant starch, and bioactive polyphenolic content, the demonstrated nutritional benefits can fill the ever‐increasing demand for plant‐based proteins well beyond traditional consumption of lentils in developing countries. This article reviews the composition and nutrient profile of raw and processed lentils, effect of various processing methods on composition and nutrient profile, and health benefits of lentils.

20-year period, the area under lentil cultivation increased by only 29%, which shows that over two third of production increase has resulted from breeding and field production interventions. It is noted that Canada, Australia, and the United States have shown exponential increases in lentil production since 2000, equaling 3.2, 3.1, and 2.5 folds, respectively.
Moreover, the wide variations in total fiber content partially could be attributed to differences in analytical methods used or methodology improvements over the years. According to the US Department of Agriculture (USDA, 2022) nutrients data, raw lentil contains 24.6% protein, 63.4% carbohydrates, 1.1% fat, and 2.7% ash content.
In comparison with common cereal grains, lentils, being high in proteins and low in carbohydrates (Figure 1), offer nutrient-dense choices for consumers looking for meat alternatives. Health-improving benefits stemming from lentil consumption have been reported in a number of biological processes, for example, inhibiting angiotensin Iconverting enzyme (ACE), aid in lowering blood cholesterol and bioactive role as an antioxidant (Khazaei et al., 2017;Patterson et al., 2017). Lentil consumption has also been reported to be effective in reducing various health problems, such as hypertension, cardiovascular diseases, diabetes mellitus, and cancer. Flour of some lentil varieties (Blaze and Laird) can bind with bile salts thereby reducing blood cholesterol levels (Barbana et al., 2011;Verni et al., 2020).
In recent years, the use of pulses, including lentils, is increasingly gaining recognition as ingredients in a variety of food product applications. This trend has aligned well with the heightened concerns about the environmental impact of producing and consuming meat. Recent trends show that consumers are reducing or foregoing meat consumption and shifting to nonmeat foods produced in a sustainable manner (Hill, 2022). Thus, environmental concern, coupled with a number of health issues stemming from meat consumption, has resulted in the ever-growing popularity of plant-based food products, which cater to many consumers far beyond the traditional vegan and vegetarian consumers. This article reviews the composition and nutrient profile of raw lentils and the effects that various cooking and processing methods have on compositional and nutrient profile of lentils. The F I G U R E 1 Protein, carbohydrate, total lipids, and ash content of lentil compared with selected cereal grains. Source: Based on data from USDA (2022) health benefits of lentils are also discussed, which can potentially help increase lentil consumption among consumers and assist food industry in offering new lentil-based products.

| COMPOSITION AND NUTRIENT PROFILE
The composition and nutrient profile of lentil (raw and cooked) is presented in Table 1. It contains about 25% protein, 63% carbohydrates, and only around 1% fat. Lentils are a rich source of dietary fiber that ranges from 11% to 31% in green and pink types, respectively. Due to a large number of varieties available for cultivation, a considerable variation in nutrient composition is reported (Joshi et al., 2017;Zia-ul-Haq et al., 2011). The protein content of cotyledons is twofolds higher than that in the seed coat of lentils (Rathod & Annapure, 2016); therefore, lentils are typically dehulled to produce high protein fractions or isolates. The amino acid profile of raw lentil seeds is presented in Figure 2. Glutamic acid is the most abundant amino acid in lentils, followed by aspartic acid, arginine, leucine, and lysine, whereas cystine, tryptophan, and methionine are at the bottom of the list with respect to their content. Thus, methionine and tryptophan are first and second limiting amino acids, respectively.
Although lentils are rich in carbohydrates and contribute a significant number of calories per serving, yet their carbohydrates are slowly digested in human gut (due to higher content of slowly digestible starch [SDS]). Thereby, lentils contribute a lower glycemic index (GI) of 29 in comparison with white bread which has a GI of 100. Generally, foods with a GI of <55 are classified as "low GI foods" and are recommended for diabetic individuals. Higher protein content and significantly dietary fiber content in lentils lead to a slower digestion of available carbohydrates. One cup (197 g) of cooked lentils contains about 15.6 g of fiber, which fulfills 62% of daily requirement. Higher dietary fiber content of lentils is helpful in regulating bowel movement T A B L E 1 Nutrient profile of raw, sprouted, and cooked (boiled, no salt) lentils and lentil soup (per 100 g) and growth stimulation of probiotics like Lactobacilli and Bifidobacteria (Zare et al., 2012). Lehmann and Robin (2007) reported that benefits of SDS are linked to a stable glucose metabolism, improved diabetes management, and overall satiety.

| EFFECT OF PROCESSING ON CHEMICAL AND NUTRITIONAL COMPOSITION OF LENTILS
Lentils are either used as cooked (whole or dehulled spilt seeds) for direct consumption or processed into different ingredients, for example, flour, protein, starch, and fiber ( Figure 3), which can be used in diverse food applications. Lentil flour and protein-and starch-rich fractions can be prepared either by dry milling or wet milling processes. The milling method used has significant effect on the functional properties of flours and fractions, which must be assessed before use in diverse food applications. Lentil flour can also be produced using extrusion technology by optimizing feed rate, moisture content, and process temperature parameters. It is to be noted that the use of raw lentil flour can result in technological or food safety problems due to the presence of some ANFs. Commercially canned lentils are available in some developed countries, whereas traditional cooking/boiling continues to be the main method in developing countries.
Different preprocessing (e.g., dehulling and milling) and processing (e.g., cooking, fermentation, soaking, and germination) F I G U R E 2 Amino acid profile of lentil, raw whole seeds (g/100 g). Also, lentil flour has a high lipoxygenase activity that can reduce the shelf life and cause off-flavors during processing and storage. All of these aspects have a significant impact on the nutritional and sensory properties, digestibility, and acceptability of lentil-based products and must be addressed using traditional and cutting-edge technologies.
The effect of different processing techniques (dehulling, splitting, milling, cooking, extrusion, germination or sprouting, and fermentation) on the composition and nutrient profile of lentils is discussed below, and detailed results reported in the literature are summarized in Table 2. In some instances, data reported showed conflicting patterns (i.e., increasing or decreasing effect) that could be attributed to differences owing to lentil varieties and/or testing methodology used.

| Dehulling, splitting, and milling
Dehulling is the process of removing the seed coat (testa/hull) while splitting involves the separation of the cotyledons in pulses. The seed coat of pulses is often somewhat bitter in taste and indigestible and its removal has been shown to improve the taste and palatability of pulses, including lentils. Dehulling and splitting is a standard practice for most lentil market classes to satisfy consumers' preference (Singh & Singh, 1992). By removing the impermeable seed covering that impedes water uptake during cooking, dehulling also decreases Recent research has shown that the degree of milling is favorably F I G U R E 3 Flowchart of lentils processing methods and resulting end product (based on Joshi et al., 2017;Sidhu et al., 2022) associated with nutritional bioaccessibility, because a thorough milling process entails an extended cell rupture (Joshi et al., 2017). Raw flour with large particle size has low digestion rates which can be due to the delayed action of digestive enzymes caused by large protein bodies or fragments of cell wall. Therefore, an understanding of different preprocessing techniques, milling, and particle size distribution on physicochemical and functional properties of lentil flours can benefit its optimal utilization in preparation of a variety of food products. Proteins increases in protein digestibility and energy value, but fat, ash, and total carbohydrates showed reduced values (Aguilera et al., 2010;Dueñas et al., 2016). Some other studies also reported a significant increase in protein content while decrease in fat content after cooking of lentils (de Almeida Costa et al., 2006;Wang et al., 2009), suggesting that cooked lentil could be considered an important vegetable protein source for vegan diets. In contrast, Nosworthy et al. (2018) reported no significant difference in the protein content of cooked lentils.

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However, amino acid composition determined as amino acid score improved after cooking of lentils (Nosworthy et al., 2017(Nosworthy et al., , 2018. Cooking is reported to improve the protein digestibility, typically measured as in vitro protein digestibility (IVPD), protein digestibilitycorrected amino acid score (PDCAAS), in vitro PDCAAS score, and protein efficiency ratio (PER) in red and green lentils (Nosworthy et al., 2018). Hefnawy (2011) also found that total essential amino acids were slightly increased while lysine, tryptophan, and total sulfurcontaining and aromatic amino acids were reduced after cooking len-  Periago et al., 1996). Like RDS, the values of SDRI and RAG also increased in cooked lentil flours. Apart from several other factors, for example, amylase inhibitor inactivation, denaturation of proteins forming envelope around starch granules, and removal of other compounds inhibiting digestibility, this increase in RDS in thermally treated flours in presence of water is mainly determined by gelatinization of starch which is accompanied by partial leaching of amylose (Piecyk et al., 2012).
Prebiotic carbohydrates in lentils, such as RFO and FOS, are known to be affected by different treatments (Wang et al., 2009), including cooking, cooling, and reheating (Johnson et al., 2015). A number of parameters, such as cooking temperature, time, and pH, affect the thermal degradation of these prebiotic carbohydrates (Courtin et al., 2009) Hefnawy (2011) reported its complete removal after cooking. Moreover, split lentil showed a greater thermal degradation of oligosaccharides (raffinose and stachyose) (Vega & Zuniga-Hansen, 2015), which could be due to no seed coat and more surface area of split lentils resulting in increased leaching and degradation of these carbohydrates. Cooking also reduced the concentration of sugar alcoholssorbitol and mannitol (Siva et al., 2018) which can be attributed to breaking of the chemical form of these sugars at high temperature (100 C), and excess water conditions (Mohamad et al., 2016).
The SDF was reported to decrease after cooking, with an increase in IDF and TDF of eight lentil varieties (Wang et al., 2009). The increase in IDF may be attributed to the formation of protein-fiber complexes due to possible chemical modification during cooking of dry seeds (Bressani, 1993). Despite the loss of SDF, the increase in IDF after cooking of lentils can be beneficial in terms of reducing glycemic responses. However, Dueñas et al. (2016) reported a decrease in the values of IDF and TDF along with SDF. Also, a general reduction in the total phenolic concentration in dietary fiber fraction of cooked lentil flours was observed as compared with raw lentil flours (Dueñas et al., 2016). Cooking was also found to effectively reduce the protease inhibitors (e.g., trypsin inhibitors), phytic acid, and tannin contents in lentils compared with the raw seeds (Hefnawy, 2011;Wang et al., 2009).
With respect to minerals, Ca, Cu, and Mn contents were increased but Fe, K, Mg, P, and Zn contents were decreased after cooking of lentils (Wang et al., 2009). Several other studies also reported a reduction in total element content after traditional or commercial cooking (Hefnawy, 2011;Ramírez-Ojeda et al., 2018;Viadel et al., 2006), which can be due to solubilization and leaching of inorganic elements into cooking water at variable rates. Also, a considerable increase was observed in the bioaccessibility of Fe and Zn in commercially cooked lentils. Most likely, this effect was due to a reduction or elimination of some antinutritional components during processing (Ramírez-Ojeda et al., 2018).
Soaking and cooking of lentils was reported to decrease the oxygen radical absorbing capacity (ORAC) values, hydroxycinnamics, catechins and procyanidins, flavonols and dihydroflavonols, flavones, and flavanones, while hydroxybenzoics and some other phenolic compounds were increased (Aguilera et al., 2010). Further, in a study on effect of boiling pretreatment on lentil flour properties, the water holding capacity, fat binding capacity, and gelling capacity of processed flour showed a significant improvement while protein solubility was decreased, whereas emulsifying and foaming properties were not affected (Ma et al., 2011).
In a comparative study of cooking lentils by boiling in water, autoclaving, and microwave cooking (Hefnawy, 2011), mineral losses by microwaving were lower than those observed in lentils cooked by boiling or autoclaving. All cooking treatments enhanced the PER value and IVPD of cooked lentils. Autoclaving and microwave cooking also reduced the concentrations and activities of trypsin inhibitors, phytic acid, and tannins (Hefnawy, 2011). A later study showed that autoclaving decreased ash, protein, and total phenolic content but increased fat, starch, and amylose content in processed lentils (Piecyk et al., 2012). With respect to starch fractions, autoclaved lentil flours showed an increase in RDS, SDRI and RAG contents but a decrease in SDS and RS contents in comparison with raw lentil flours (Piecyk et al., 2012).

| Extrusion and baking
In extrusion processing, ingredients are forced through a specifically designed die after being exposed to expansion-inducing temperatures which can affect the nutritional quality and ANFs in lentils (Nosworthy et al., 2018;Pasqualone et al., 2021;Rathod & Annapure, 2016). It is commonly recognized that numerous extrusion processing parameters (e.g., moisture content, flow rate, and extruder design) significantly influence shear conditions that result in differential heating and different functional properties of the food. Extrusion has been reported to enhance the IVPD and in vitro starch digestibility (IVSD) without affecting the total protein content (Rathod & Annapure, 2016). However, Nosworthy et al. (2018) (Nosworthy et al., 2018). Further, these researchers reported that PER values were variety dependent, that is, the highest PER was shown in cooked red lentil flour versus extruded green lentil flour (Figure 4).
The decrease in lipid content during extrusion can be due to formation of starch-lipid/amylose-lipid complexes which reduces their extraction and quantification (Kamau et al., 2020). The formation of these complexes requires gelatinization of starch which increases amylose availability for complexation. The amylose double helix expands during heating which allow lipid molecules to fit and form electrostatic bonds to enhance stability. During extrusion, high shear forces and heat transfer can change the physicochemical properties of dietary fiber which can result in a reduction of TDF and IDF (Kamau et al., 2020). After their study on extruded cereal, Espinosa-Ramírez et al. (2021) indicated that pseudo-cereal and legume flours that showed a decrease in protein content in some studies are somewhat controversial because no effluents resulting in fraction lost were produced during extrusion process. Also, denaturation of protein resulting from extrusion does not affect the quantification of proteins.
Regarding extrusion conditions, Pasqualone et al. (2021) concluded that milder and more severe extrusion conditions had no effect on total protein content; however, lipids, carbohydrates, and dietary fiber content differed for the extruded flours processed at different conditions.
Different functional compounds such as soluble fiber, total phenolic, hydroxybenzoic, and hydroxycinnamic acids increased while insoluble fiber, flavonols, tocopherols, and most organic acids were reduced in the extrudates from fiber-enriched lentil-based flours (Morales et al., 2015). The release of fiber-bound phenolics as a result of extrusion, which increased their availability, could explain the increase in antioxidant activity in majority of the formulated flours after extrusion. Different ANFs also reduced in extruded lentils, for example, phytic acid by 99.30%, tannins by 98.83%, and trypsin inhibitors by 99.54% (Rathod & Annapure, 2016). In another study, extrusion resulted in a significant increase in total α-galactosides (raffinose, stachyose, and verbascose), while inositol phosphates, lectins, and trypsin inhibitor activity were significantly reduced (Ciudad-Mulero et al., 2020).
Regarding dough rheological properties and techno-functional parameters of extruded lentil flour, extrusion increased the viscoamylograph initial viscosity, lowered the degree of starch retrogradation, increased water absorption index and oil absorption capacity, and decreased the bulk density compared with native flour (Pasqualone et al., 2021).  studied the effect of extrusion temperature (ET) and feed moisture (FM) and concluded that different polypeptides degradation increased with decrease in FM and increase in ET. Also, the digestibility of extrudates improved at high FM and low ET. The extrudates showed lower viscosity, expansion ratio, and IVPD after increase in FM, whereas higher FM resulted in improved oil absorption capacity while water absorption capacity decreased with increase in both FM and ET. Also, at higher FM and lower ET, foaming capacity increased while viscosity decreased in lentil extrudates. It was concluded that pulses cooked at low FM can be utilized in preparation of ready-to-eat puddings with high protein, enhanced digestibility, and improved viscosity.
Another heat processing treatment, that is, baking showed slight increase in crude fat and crude protein contents (Nosworthy et al., 2018). Baking also resulted in lower amino acid score, %TPD, F I G U R E 4 Protein efficiency ratio (PER) values of extruded, cooked and baked red and green lentil flour (significant differences defined as *p ≤ 0.05, **p ≤ 0.01, and ***p ≤ 0.001) PDCAAS, and in vitro PDCAAS in comparison with cooked and extruded red and green lentil flours.

| Germination
1 method to enhance the health benefits of pulses by improving the nutritional value, boosting antioxidant capacity, and reducing the ANFs (Nadtochii et al., 2019;Xu, Jin, Simsek, et al., 2019). The nutritional, physiological, and textural attributes of grains are modified during germination by activation of endogenous enzymes and breakdown of large molecules (e.g., starch and proteins) which consequently improve their bioavailability (Nadtochii et al., 2019). Germinated lentil showed a significant increase in protein content (Fouad & Rehab, 2015;Xu, Jin, Simsek, et al., 2019) and a decrease in starch content (Ghavidel & Prakash, 2007;Xu, Jin, Simsek, et al., 2019). During germination, protein increase can be explained by (i) enzyme synthesis by germinating seed; (ii) degradation of other constituents leading to compositional change; and (iii) formation of new proteins. A number of hydrolytic enzymes such as α-amylase, glucosidase, and dextranase generated from the aleurone layer of seed coat and β-amylase from the endosperm get activated at the time of germination of seeds (Olaerts et al., 2016;Sindhu et al., 2019). The decrease in starch content during germination can be due to conversion of starch into monosaccharides or oligosaccharides by these hydrolytic enzymes and respiratory processes.
The lipid content and nonstarch carbohydrates including TDF, IDF, and SDF content were also decreased after germination (Xu, Jin, Simsek, et al., 2019). Crude lipids mainly reside in the germ of the seeds which is mainly hydrolyzed to free fatty acids (FFAs) by the enzymes produced during germination. These FFAs undergo β-oxidation in cytosol and mitochondria to produce required energy to support the growth of seeds which result in the decrease of crude fat during germination (Cornejo et al., 2015). Germination has also been found to develop distinctive green, fishy, and beany flavors in selected pulses including lentil, mainly due to increased aromatic compounds derived from lipid oxidation (Xu, Jin, Lan, et al., 2019).
The increase in the lipoxygenase activity corresponding to decrease in crude lipid content in germinated seeds also supported this hypothesis (Xu, Jin, Simsek, et al., 2019). In another study, Dueñas et al. (2016) reported that germination produced a decrease in protein, IDF, SDF, and TDF and an increase in ash, fat, and total carbohydrate content in lentils. Swieca et al. (2013) studied the effect of different sprouting method on starch content and expected GI (eGI) and concluded that sprouting conditions can differentially change the starch content, eGI, and bioavailability of starch. However, germination under all conditions resulted in decreased total starch (TS), α-amylase inhibitor activity (aAI), and eGI. Regarding sprouting conditions, control sprouts resulted in highest TS content while sprouts induced with 300 mM NaCl showed lowest TS content; sprouts with 300 mM NaCl showed highest eGI while sprouts with 100 mM NaCl showed the lowest value; and highest RS content was found in sprouts with 600 mM mannitol compared with other sprouting conditions (Świeca et al., 2013). In another study, Świeca and Gawlik-Dziki (2015) reported an increase in available starch, starch digestibility, eGI, total phenolics, flavonoids, and reducing power, but a reduction in TS and antiradical activity during germination of lentils.
Flours prepared from germinated lentils showed increased water absorption capacity and final viscosities in comparison with raw lentil flours (control). However, thermal properties showed a slight change in germinated lentil flours (Xu, Jin, Simsek, et al., 2019). Germinated lentil flour showed an improvement in protein content, water absorption capacity, foaming capacity, and breakdown viscosity, but paste viscosities, emulsifying activity index, and foaming stability reduced compared with raw lentil flour . Also, high molecular weight (HMW) proteins decreased while low molecular weight (LMW) proteins increased due to hydrolysis of HMW to LMW proteins by proteases during germination. However, polypeptides corresponding to trypsin inhibitors are not affected significantly by germination.

| Fermentation
Fermentation has the potential to improve the nutritional qualities of lentils by improving the content and bioavailability of bioactive compounds thereby making it an attractive method for developing innovative lentil-based foods. Endogenous enzyme activity is activated during fermentation of lentil, resulting in hydrolytic processes as α-amylase breaks down the raw starch . Functional characteristics of legumes can be enhanced using fermentation with selected starters (Bautista-Exp osito, Peñas, Dueñas, et al., 2018;Dhull, Punia, Kumar, et al., 2020;Yeo et al., 2021). Lactic acid bacteria (LAB) such as Lactobacillus plantarum used as starter in legume fermentation produces a number of carbohydrolases and esterases which resulted in an increase in the free phenolic compounds (Gan et al., 2016) and enhanced the antioxidant, antihypertensive, and hypolipidemic activities of the fermented product (Torino et al., 2013). increasing time, the protein content decreased during fermentation which is due to L. plantarum proteolytic enzymes leading to proteolysis and production of peptides and free amino acids (De Angelis et al., 2016). The pH is a dominating factor during fermentation as uncontrolled fermentation by LAB leading to acidification can cause protein precipitation and enzyme inactivation (Rui et al., 2016) which can cause hindrance in release of bound phenolics and the generation of bioactive peptides.
In another study, Bautista-Exp osito, Peñas, Dueñas, et al. (2018) also confirmed an increase in bioactive peptides, ACE inhibitory activity, and maltase inhibitory activity but a significant decrease in total phenolic compounds, α-glucosidase inhibition, sucrase inhibitory activity, and ORAC value of lentils fermented by L. plantarum. Fermentation by Rhizopus oryzae resulted in the efficient release of insoluble-bound phenolics from the cell wall matrix; however, these released bound phenolics were not completely transformed into accessible soluble phenolics due to structural changes during fermentation.
Several studies have reported an increase in antioxidant potential and phenolic compounds of lentils after fermentation with starter culture such as Bacillus subtilis, Aspergillus oryzae, Aspergillus niger, and Aspergillus awamori (Dhull, Punia, Kidwai, et al., 2020;Magro & de Castro, 2020;Torino et al., 2013). An increase in mineral contents (Fe, Zn, Ca, Cu, Na, and K) and in vitro bioavailability of Fe and Zn of lentils after solid-state fermentation was also reported (Dhull, Punia, Kidwai, et al., 2020).

| HEALTH BENEFITS OF LENTILS
Lentils are rich in protein, dietary fiber, complex carbohydrates, iron, zinc, folate, potassium, manganese, and plant chemicals called polyphenols that have antioxidant activity, and lentils are low in sodium and saturated fat (Khazaei et al., 2017). Consumption of lentils has been associated with lower risk of metabolic syndrome, a combination of factors that increases the risk of developing heart disease and diabetes. Factors associated with the metabolic syndrome include high blood pressure, high insulin levels, overweight (especially, around the abdomen), high levels of triglycerides, and low levels of HDL or highdensity lipoproteins, that is, "good cholesterol." High intake of fiber may offer protective benefits from this syndrome (McKeown et al., 2004), diverticular disease, and constipation. Eating lentils, particularly the insoluble component of fiber, was associated with about a 40% lower risk of diverticular disease (Aldoori et al., 1998). Fiber in lentils is also a source of prebiotics to help prevent digestive diseases (Ganesan & Xu, 2017). A large-scale study of 90,534 women subjects showed that early adulthood high fiber intake reduces the risk of breast cancer (Farvid et al., 2016). Other human studies have found that consumption of lentils may improve cholesterol levels in people with diabetes mellitus and may protect against breast cancer in women (Adebamowo et al., 2005;Aslani et al., 2015).
Potassium is an essential nutrient needed for maintenance of total body fluid volume, acid and electrolyte balance, and normal cell function. The high amounts of potassium help to counteract the effects of salt (sodium) thereby lowering blood pressure. Increased potassium intake reduced systolic and diastolic blood pressure in adults (World Health Organization, 2020).
Folate is important for maturation of red blood cells hence prevents megaloblastic anemia and protects the heart by effectively lowering the levels of homocysteine, an amino acid in the blood, which is linked to heart diseases. For pregnant women, folate is important for normal development of the fetus and prevents birth defects, for example, anencephaly and spina bifida (CDC, 2021). Anencephaly occurs when parts of the fetal brain and skull do not form correctly.
Spina bifida is a condition in which the spine of the fetus does not develop correctly and can result in some severe physical disabilities.
Lentils are a good source of iron, which is used in the body in the manufacture of red blood cells. These cells are important for the transportation of oxygen from the lungs to the cells to be used for generation of energy and therefore help to prevent fatigue.

| CONCLUSION
Legumes, including lentils, have gained increasing popularity among consumers and food processors in recent years. This popularity has been driven by the fact that legumes are high in protein content and relatively low in carbohydrates as compared with cereal grains, and high content of RS, and their low GI. The economic significance of lentils is evident from the exponential growth of lentils production in countries beyond the traditional leading producer, India. During the same two decades, Canada, Australia, and the United States have shown 323%, 314%, and 245% increase in lentil production, respectively. Besides being high in proteins and dietary fiber content, lentils are a rich source of many bioactive compounds with demonstrated nutritional and health benefits. Lentil consumption has been reported to be effective in reducing various health conditions, such as hypertension, cardiovascular diseases, diabetes milieus, and cancer.
Processing is necessary to produce a variety of products, make lentils palatable, and significantly reduce antinutrients. However, different processing techniques, such as dehulling, splitting, milling, cooking, extrusion, germination or sprouting, and fermentation, have a significant effect on the composition and nutritional profile of lentil end products.
Overall, lentils are ideal in meeting the sustainable development goals by virtue of their nutritional, health, and environmental benefits.
Modern genetic engineering and breeding approaches are being employed to produce stress-resistant (abiotic/biotic), climate-smart, and high-yield lentil varieties with better nutritional and functional characteristics. Most of the lentil is generally consumed either as whole grain or in decorticated form; however, advanced processing technologies has opened new avenues for further application of its protein and starch in different food formulations such as in baby foods, pulse snacks, pulse protein concentrates, meat alternatives, and bakery products. These types of product are easy to be incorporated into different diets according to the consumer's preference. However, the nutritional and functional properties of lentil ingredients must be optimized and assessed for food applications to ensure consumer acceptance. The processing techniques can also be tailored to purpose and lentil type to achieve desired results and increase the varieties of lentil-based products for consumers.