Cooked Legumes Research Articles

Effect of Cooking on Protein Digestion and Antioxidant Activity of Different Legume Pastes.

Legumes are protein-rich foods that can be used to prepare pastes or pureed foods suitable for babies and the elderly. The aims of this study were the characterization of different legume pastes (from soybean, lentil, and pea) subjected to three processing methods (ordinary cooking, pressure cooking, and microwave) and the evaluation of protein digestion and antioxidant activity during simulated gastrointestinal digestion (GID). The different cooking methods of legumes led to differences in the physicochemical properties of the pastes, as well as on the textural and viscoelastic characteristics, except for soybean samples, despite all the pastes presenting elastic properties and weak gel behavior. Cooking followed by GID improved the protein digestibility and antioxidant activity of the legumes, which was attributed to released peptides and amino acids more than free phenolics. However, the fate and extent at each digestion stage was different according to the legume type and cooking method, as it would be influenced by the matrix structure and interaction between components. This work has expanded knowledge about the properties, digestibility, and antioxidant activity of different cooked legumes for a future design of pastes.

Impacts of Protease Treatment on the Contents of Tocopherols and B Vitamins in Peanuts

This study investigated the changes of tocopherols and B vitamins in raw peanuts as a result of protease treatment which was used to reduce peanut allergens. Raw peanut kernels were treated with Alcalase, bromelain, Neutrase and papain separately at different concentrations, vacuum dried, and then ground into paste. The paste was defatted using hexane containing 0.02% BHT to obtained crude oil and defatted peanut flour which were used for tocopherol and B-vitamin analysis, respectively. The protease treatment significantly reduced the contents of all tocopherols and B-vitamins in the peanuts in enzyme concentration-dependent manner (P<0.0001). The highest losses of α-, γ-, and δ-tocopherols were 60.87 %, 40.60 % and 36.89 %, respectively, while the maximum losses of vitamins B1, B2, B3 and B6 were 63.29 %, 44.83 %, 40.56 % and 49.59 %, respectively. Among tocopherols, α-tocopherol was the most affected while δ-tocopherol was the least affected. Among B-vitamins, B1 was the most affected and B3 the least affected. This study demonstrated that although the protease treatment approach (including enzyme treatment and drying) for peanut allergen reduction resulted in different degrees of losses in tocopherols and B vitamins in raw peanuts, the enzyme treated peanuts is still a good source of tocopherols and vitamin B3 comparing to most cooked legumes and vegetable.

Nutritional properties of green gram germinated in mineral fortified soak water: II. Effect of cooking on total and bioaccessible nutrients and bioactive components.

The effect of pressure and microwave cooking on total and bioaccessible nutrients and bioactive components in whole and dehulled green gram (GG) germinated in mineral fortified soak water was studied. Whole GG was soaked in water fortified with iron (100 or 200mg/100ml) or zinc (50 or 100mg/100ml), germinated, cooked by two methods and analyzed. Results showed that method of cooking did not affect the nutrient composition of whole or dehulled grains, however, phytic acid and dietary fiber were higher in microwave cooked samples. Minor differences were noted in total and percent available nutrients in differently cooked samples, significance being observed only for starch, protein and zinc in few samples. Significant differences were observed among variations, wherein the mineral fortified samples had a higher level of bioaccessibility compared to non-fortified samples. Cooking reduced the content of bioactive components in germinated GG, though bioaccessibility was higher. Comparison between raw and cooked grains showed that starch digestibility increased on cooking, though protein digestibility was not affected significantly. Bioactive components were also lower in cooked samples in comparison to the raw counterparts. In conclusion, the cooking methods did not affect the nutrient composition of green gram germinated in mineral fortified soak water, though available nutrients were higher in cooked legumes.

Determination of Soyasaponins I and βg in Raw and Cooked Legumes by Solid Phase Extraction (SPE) Coupled to Liquid Chromatography (LC)–Mass Spectrometry (MS) and Assessment of Their Bioaccessibility by an in Vitro Digestion Model

Legumes contain a rich variety of phytochemicals as soyasaponins, triterpenoidal glycosides that possess multiple health-promoting properties, such as lowering of cholesterol. In this work, the quantification of soyasaponins I and βg in 60 raw and cooked legumes by using a solid phase extraction (SPE) coupled to a liquid chromatography (LC)-mass spectrometry (MS) method was carried out. Results showed that lentils are a good source of soyasaponins, with a content of soyasaponin I that ranged from 636 to 735 mg kg(-1) and of soyasaponin βg from 672 to 1807 mg kg(-1). The cooking process produced a small loss of soyasaponins in water, that is, 4.8-8.7%, and partially converted soyasaponin βg into soyasaponin I. In addition, the bioaccessibility of soyasaponins I in lentils was studied; the values ranged from 8.9 ± 0.3 to 10.6 ± 1.1% in the duodenal compartment. On the basis of these results, soyasaponins could be effective in lowering exogenous cholesterol.

Iron and Folate Contents of Tajik Legumes

Seven varieties of Tajik legumes and two Tajik snack type ready-to-eat (RTE) whole/split chickpeas were analyzed for iron in raw and cooked legumes and for naturally occurring folate content in cooked legumes. Iron was measured according to AACC method 40 - 41B. Folate contents were determined by microbiological (Lactobacillus casei subsp. Rhamnosus ATCC 7469) and high-performance liquid chromatography analysis utilizing a tri-enzyme treatment (pro-tease, α-amylase and conjugase). Folate derivatives of tetrahydrofolate, 5-formyl-tetrahydrofolate and 5-methyl- -tetrahydrofolate were identified and quantified. Iron content for Tajik legumes ranged from 5.52 to 13.27 mg/100 g for raw; 2.81 to 4.12 mg/100 g for cooked and 4.37 and 4.76 mg/100 g for RTE chickpeas. The total folate content of cooked legumes ranged from 53 to 81 µg/100 g for beans; 133 to 203 µg/100 g for peas, and from 39 to 22 µg/100 g for small and large lentils, respectively. The predominant form of folate in legumes was tetrahydrofolate, followed by 5-formyl-tetrahydrofolate and 5-methyl-tetrahydrofolate.

Effect of soaking, boiling, and steaming on total phenolic contentand antioxidant activities of cool season food legumes

The effects of soaking, boiling and steaming processes on the total phenolic components and antioxidant activity in commonly consumed cool season food legumes (CSFL’s), including green pea, yellow pea, chickpea and lentil were investigated. As compared to original unprocessed legumes, all processing steps caused significant (p<0.05) decreases in total phenolic content (TPC), DPPH free radical scavenging activity (DPPH) in all tested CSFL’s. All soaking and atmospheric boiling treatments caused significant (p<0.05) decreases in oxygen radical absorbing capacity (ORAC). However, pressure boiling and pressure steaming caused significant (p<0.05) increases in ORAC values. Steaming treatments resulted in a greater retention of TPC, DPPH, and ORAC values in all tested CSFL’s as compared to boiling treatments. To obtain cooked legumes with similar palatability and firmness, pressure boiling shortened processing time as compared to atmospheric boiling, resulted in insignificant differences in TPC, DPPH for green and yellow pea. However, TPC and DPPH in cooked lentils differed significantly between atmospheric and pressure boiling. As compared to atmospheric processes, pressure processes significantly increased ORAC values in both boiled and steamed CSFL’s. Greater TPC, DPPH and ORAC values were detected in boiling water than that in soaking and steaming water. Boiling also caused more solid loss than steaming. Steam processing exhibited several advantages in retaining the integrity of the legume appearance and texture of the cooked product, shortening process time, and greater retention of antioxidant components and activities.

Chemical composition, dietary fibre and resistant starch contents of raw and cooked pea, common bean, chickpea and lentil legumes

The chemical composition and the contents of resistant starch and soluble and insoluble dietary fibre of pea ( Pisum sativum L.), common bean ( Phaseolus vulgaris L.), chickpea ( Cicer aretinum L.) and lentil ( Lens culinaris Med.) legumes, were studied. Raw and freeze-dried cooked samples were used, both in the form of flour. Protein values of the legumes ranged from 18.5 to 21.9 g/100 g for the raw grains and from 21.3 to 23.7 g/100 g for freeze-dried cooked legumes. Chickpea stood out for the highest lipid content ( p < 0.05), the lowest insoluble fibre values, and soluble dietary fibre not detected. The average content of resistant starch found in the legumes did not differ statistically ( p > 0.05), being 2.23 ± 0.24 g/100 g for freeze-dried cooked legumes, and showing a slight reduction in comparison to the raw form.

Resistant starch and potential glycaemic index of raw and cooked legumes (lentils, chickpeas and beans)

The amount of resistant starch (RS) in raw and processed legumes, lentils, chickpeas and beans was analysed. In addition, the effect of cooking on the availability of legume starches to enzymes, which may influence the glycaemic response, was studied. Raw legumes were found to have higher RS values (16–21%) than retrograded or cooked ones (4–8%). Cooling increased RS yields, whereas reheating maintained or decreased the value depending on the sample. On the other hand, the kinetics of starch hydrolysis revealed that the rate of digestion was higher for cooked seeds and retrograded flours (15–21% of total starch digested) than for raw flours (5–8% of total starch digested). The estimated glycaemic indices (GIs), i.e. GI1 from the Hydrolysis Index (HI) and GI2 from the percentage of hydrolysis within 90 min (H 90), were well correlated with the reported GI values (r = 0.96 and r = 0.95 respectively, P≤ 0.05).

Binding of Ca by three starchy legumes in the presence of Ca alone or with Fe, Zn, Mg and Cu

The Ca-binding capacity of butter beans, broad beans and lentils in the raw, cooked and fibre-rich fraction (FRF) forms, with Ca addition alone and with Fe, Zn, Mg and Cu (at amounts based on the recommended daily allowance), was investigated in conditions simulating the small intestine. Overall, more Ca was bound when Ca was added with Fe, Zn, Mg and Cu than when Ca was added alone. Cooking significantly increased the Ca-binding capacity of the raw legumes when Ca was added alone. The FRFs gave the highest Ca-binding capacity in comparison to the raw and cooked legumes. The results suggest that the mineral-binding capacity of dietary fibre may influence mineral absorption.

Pantothenic Acid and Biotin Retention in Cooked Legumes

ABSTRACTSamples of legumes were analyzed raw for panfothenic acid and biotin. Pooled samples were prepared in one of three cooking times: 20, 90 or 150 min. For each cooking time legumes were presoaked with a short or long soak treatment. Average pantothenic acid retention in those cooked 20 min was 76% without pre‐soak, 33% for short, and 44% for long soak. Biotin retention was 95% without pre‐soak, 86% for short and 90% for long soak. In the 90 min group, retention differed between short soak and long soak for pantothenic acid (40% vs 58%), but not for biotin (98% vs 92%). No difference (P &gt; 0.05) occurred in retention between short soak and long soak in the 150 min group for either nutrient. Biotin losses were minimal compared to pantothenic acid and methods of preparation could affect vitamin retention in legumes.

Simplified Enzymatic‐gravimetric Method for Total Dietary Fiber In Legumes Compared with a Modified AOAC Method

ABSTRACTTwo methods (an AOAC and a simplified enzymatic‐gravimetric method) were used to analyze seven types of canned legumes and eight cooked legumes. Total dietary fiber (TDF) of the canned products ranged between 17% and 23% (dry basis) for chick peas, Great Northern beans, kidney beans, pinto beans, pork &amp; beans, vegetarian beans in tomato sauce, and 27–31% for wax beans. These values were comparable for both methods. However, results on cooked legumes were very different between methods. TDF values for several types of beans and peas were higher and ranged between 31% and 5.5% by the AOAC/Tris‐Mes buffer method as compared to 17% and 29% using the simplified method. Chemical analysis of dietary fiber residues showed the major difference between the methods was in the extent of starch removal as affected by starch gelatinization.

Comparative effects of four legume species on plasma lipids and faecal steroid excretion in hypercholesterolaemic pigs

The effect of four species of legume seeds on plasma cholesterol levels and faecal steroid excretion was studied in pigs. Thirty-six growing boars were randomly allocated in groups of six to six diets which they ate continuously for 42 d. The diets fed were: 1, a semi-purified (SP; control group 1) diet; 2, SP + 10 g cholesterol/kg (control group 2); 3, 4, 5, 6, SP + cooked legumes (70:30, w/w; respectively baked beans (Phaseolus vulgaris), peas (Pisum sativum), lentils (Lens culinaris Medik.), butter beans (Phaseolus lunatus)) + 10 g cholesterol/kg. Fasting blood samples were taken on days 0, 14, 28, and 42 for the determination of total plasma cholesterol, high-density-lipoprotein (HDL)-cholesterol and triacylglycerols. Between days 7 and 11 and days 28 and 32 complete 5 d faecal collections were made for the measurement of neutral, acidic and conjugated steroids. After 42 d total cholesterol and HDL-cholesterol levels were raised significantly in all groups, but to different extents. In comparison with control group 2, diet-induced hypercholesterolaemia was significantly inhibited in the groups consuming baked beans, peas and butter beans, although HDL-cholesterol levels were maintained. Faecal steroid excretion by the legume groups was not significantly different from that of control group 2. The results suggest that the mechanism for the hypocholesterolaemic effect does not involve increased hepatic bile acid synthesis and thereby increased cholesterol clearance via the intestinal route.

Trypsin Inhibitor Activity and Tannin Content Do Not Affect Calcium Bioavailability of Three Commonly Consumed Legumes

ABSTRACTCalcium bioavailability from legumes containing a range in trypsin inhibitor activity (TIA) and tannin concentration was studied. Three cultivars (Phaseolus vulgaris) were hydroponically grown and intrinsically labeled with 4SCa. Raw and cooked legumes were fed to six groups of 6‐wk old male Sprague‐Dawley rats. Another group received an intraperitoneal (IP) injection of 45Ca. An eighth group was fed a casein metal extrinsically labeled with 45Ca. The absorption of calcium from legumes by rats averaged 47.1 ± 7.5% of IP dose. Average phytate content of the legumes was 1.7% and oxalate 0.37%. Raw legumes had an average of 15000 TIA units/g of whole bean, which were completely removed by cooking. Calcium absorption was unaffected by TIA or tannin content. Reduced availability of bean calcium was likely due to phytate and/or oxalate present in legumes.

The pathogenesis of oral pulse granuloma: an animal model

Oral pulse granuloma is one of the terms used to describe oral inflammatory lesions characterized microscopically by the presence of giant cells and hyaline rings. The various names proposed for these lesions reflect the lack of agreement regarding their pathogenesis. One theory advanced claims that the process represents a foreign-body granulomatous reaction to implanted vegetable particles, more specifically those of pulses/legumes. In this study an animal model was developed where homogenized cooked legumes were implanted into the orofacial region of rats. Animals were killed at varying intervals ranging from one day to six months and the tissues associated with the implanted material were removed and processed for light microscopy. The experimentally produced lesions had many features similar to those found in humans, the similarities becoming more pronounced with time. The results indicate that the cellulose moiety of food particles of plant origin accidentally implanted into human tissues may cause the granulomatous reaction known as oral pulse granuloma.