Effect of chemical composition and thermal properties on the cooking quality of common beans (Phaseolus vulgaris)

Targeted hydrothermally induced cell biopolymer changes explain the in vitro digestion of starch and proteins in common bean (Phaseolus vulgaris) cotyledons

Digestion of macro-nutrients (protein and starch) in pulses is a consequence of the interplay of both extrinsic (process-related) and intrinsic (matrix-dependent) factors which influence their level of encapsulation and physical state, and therefore, their accessibility by the digestive enzymes. The current work aimed at understanding the consequences of hydrothermally induced changes in the physical state of cell biopolymers (cell wall, protein, and starch) in modulating the digestion kinetics of starch and proteins in common beans. The hydrothermal treatments were designed such that targeted microstructural/biopolymer changes occurred. Therefore, bean samples were processed at temperatures between 60 and 95 °C for 90 minutes. It was demonstrated that these treatments allowed the modulation of starch gelatinization, protein denaturation and cell separation. The specific role of hydrothermally induced starch gelatinization and protein denaturation, alongside enhanced cell wall permeability on the digestion kinetics of common bean starch and proteins is illustrated. For instance, bean samples processed at T > 70 °C were marked by higher levels of starch digestibility (Cf values above 47%) compared to the partially (un-)gelatinized samples (processed at T ≤ 70 °C) (Cf values below 35%). Similarly, samples processed at T > 85 °C exhibited significantly higher levels of protein digestibility (Cf values above 47%) resulting from complete protein denaturation. Moreover, increased permeability of the cell wall to digestive enzymes in these samples (T > 85 °C) increased levels of digestibility of both gelatinized starch and denatured proteins. This study provides an understanding of the potential use of hydrothermal processing to obtain pulse-based ingredients with pre-determined microstructural and nutritional characteristics.

Effect of cooking on structural changes in the common black bean (Phaseolus vulgaris var. Jamapa)

The cooking process is fundamental for bean consumption and to increase the bioavailability of its nutritional components. The study aimed to determine the effect of cooking on bean seed coat through morphological analyses with different microscopy techniques and image analyses. The chemical composition and physical properties of raw black bean (RBB) and cooked black bean (CBB) seeds were determined. The surface and cross-sectional samples were studied by Optical microscopy (OM), environmental scanning electron microscopy (ESEM), atomic force microscopy (AFM) and confocal laser scanning microscopy (CLSM). The composition of samples showed significant differences after the cooking process. OM images and gray level co-occurrence matrix algorithm (GLCM) analysis indicated that cuticle-deposited minerals significantly influence texture parameters. Seed coat surface ESEM images showed cluster cracking. Texture fractal dimension and lacunarity parameters were effective in quantitatively assessing cracks on CBB. AFM results showed arithmetic average roughness (Ra) (121.67 nm) and quadratic average roughness (Rq) (149.94 nm). The cross-sectional ESEM images showed a decrease in seed coat thickness. The CLSM results showed an increased availability of lipids along the different multilayer tissues in CBB. The results generated from this research work offer a valuable potential to carry out a strict control of bean seed cooking at industrial level, since the structural changes and biochemical components (cell wall, lipids and protein bodies) that occur in the different tissues of the seed are able to migrate from the inside to the outside through the cracks generated in the multilayer structure that are evidenced by the microscopic techniques used.

Common beans as a source of food ingredients: Techno-functional and biological potential

Common beans are an inexpensive source of high-quality food ingredients. They are rich in proteins, slowly digestible starch, fiber, phenolic compounds, and other bioactive molecules that could be separated and processed to obtain value-added ingredients with techno-functional and biological potential. The use of common beans in the food industry is a promising alternative to add nutritional and functional ingredients with a low impact on overall consumer acceptance. Researchers are evaluating traditional and novel technologies to develop functionally enhanced common bean ingredients, such as flours, proteins, starch powders, and phenolic extracts that could be introduced as functional ingredient alternatives in the food industry. This review compiles recent information on processing, techno-functional properties, food applications, and the biological potential of common bean ingredients. The evidence shows that incorporating an adequate proportion of common bean ingredients into regular foods such as pasta, bread, or nutritional bars improves their fiber, protein, phenolic compounds, and glycemic index profile without considerably affecting their organoleptic properties. Additionally, common bean consumption has shown health benefits in the gut microbiome, weight control, and the reduction of the risk of developing noncommunicable diseases. However, food matrix interaction studies and comprehensive clinical trials are needed to develop common bean ingredient applications and validate the health benefits over time.

Soaking beans for 12 h reduces split percent and cooking time regardless of type of water used for cooking

Beans are one of the most important cheap source of protein in developing countries. However, their utilisation in the diets of many people remains limited due to long cooking time, among others. Therefore, it is imperative to identify ways to enhance utilisation of beans. The aim of the current study was to assess the effects of soaking and cooking in different types of water (tap, borehole, acidulated- 1.0 percent citric acid and soda- 0.2 percent sodium bicarbonate) on cooking time (CT), split percentage (SP) and total soluble solids (TSS) in broth of different varieties of beans. Results show that soaking significantly reduced CT across eight varieties from an average CT of 109.5–84.6 min in tap water, 109.5–85.2 min in borehole water, 115.9–92.7 min in acidulated water and 82.0–51.2 min in soda water representing 22.7%, 22.1%, 20.0% and 37.6% reduction in CT, respectively. Soaking generally decreased SP and varietal differences were observed suggesting beans are less likely to break when soaking precede cooking. Although cooking in soda water significantly reduced CT, unfortunately, it increased SP. Acidulated water extended CT but reduced SP in almost all varieties. Soaking generally decreased TSS in broth from 7.0 to 6.7% in tap water, 6.1–5.8% in borehole water and 11.3–7.7% in soda water while it increased TSS in acidulated water from 18.2 to 20.6% across all the eight varieties which suggest reduction in leaching out of bean solids into cooking water which is consistent with reduced SP of soaked beans. While use of soda water reduced cooking time and therefore saved time and energy, its effect of increasing split percent may not be appealing to some consumers. This study has demonstrated that bean soaking significantly reduced cooking time and split percent and these can also be affected by type of cooking water.

Hybrid Meat Products: Incorporation of White Bean Flour in Lean Pork Burgers

The effect of partial lean pork-meat replacement by white Phaseolus vulgaris L. flour in hybrid burgers was studied. A multivariate regression model was used to test different bean flour levels (BF: 8–15 g/100 g) and water/bean flour ratios (W/BF: 1.2, 1.6, and 1.8 g/g). Process yield, texture profile analysis, color parameters, thermal transitions, and microstructure of the systems were analyzed. Respond Surface Methodology was used to model the response behaviors and optimization. Burgers with BF showed yields higher than 88%. Hardness and cohesiveness decreased as the BF level increased, with a more noticeable effect when the W/BF ratio became larger. Regarding color, the higher the BF and the W/BF ratio in burgers, the higher the L* obtained. The desirability optimization predicted an optimum formulation consisting of 15 g BF/100 g and 1.36 g/g W/BF with similar attributes to a commercial pork burger. The thermal analysis showed an increase in the enthalpy associated with the myosin denaturation and the interactions between meat proteins and BF led to higher temperatures for the starch gelatinization and protein denaturation. The microstructure of BF burgers presented a more stable coarse gel matrix derived from coagulated meat proteins combined with the flour components. The mathematical procedure adequately predicted the hybrid burger quality attributes.

Combined Effects of Calcium Addition and Thermal Processing on the Texture and In Vitro Digestibility of Starch and Protein of Black Beans (Phaseolus vulgaris)

Legumes are typically soaked overnight to reduce antinutrients and then cooked prior to consumption. However, thermal processing can cause over-softening of legumes. This study aimed to determine the effect of calcium addition (0, 100, 300, and 500 ppm in the form of calcium chloride, CaCl₂), starting from the overnight soaking step, in reducing the loss of firmness of black beans during thermal processing for up to 2 h. The impact of calcium addition on the in vitro starch and protein digestibility of cooked beans was also assessed. Two strategies of calcium addition were employed in this study: (Strategy 1/S1) beans were soaked and then cooked in the same CaCl₂ solution, or (Strategy 2/S2) cooked in a freshly prepared CaCl₂ solution after the calcium-containing soaking medium was discarded. Despite the texture degradation of black beans brought about by increasing the cooking time, texture profile analysis (TPA) revealed that their hardness, cohesiveness, springiness, chewiness, and resilience improved significantly (p < 0.05) with increasing calcium concentration. Interestingly, beans cooked for 2 h with 300 ppm CaCl₂ shared similar hardness with beans cooked for 1 h without calcium addition. Starch and protein digestibility of calcium-treated beans generally improved with prolonged cooking. However, calcium-treated beans cooked for 1 h under S2 achieved a reduced texture loss and a lower starch digestibility than those beans treated in S1. A lower starch digestion could be desired as this reflects a slow rise in blood glucose levels. Findings from this result also showed that treating black beans with high level of CaCl₂ (i.e., 500 ppm) was not necessary, otherwise this would limit protein digestibility of cooked black beans.

Black bean protein concentrate ameliorates hepatic steatosis by decreasing lipogenesis and increasing fatty acid oxidation in rats fed a high fat-sucrose diet

The black bean is a legume widely consumed in Latin America, however its consumption has decreased significantly in recent decades. There is evidence that its consumption generates beneficial health effects due in part to the type of protein, resistant starches and polyphenols. Thus, their use in food formulation could impact health status. Therefore, the purpose of the present work was to evaluate the effects of the consumption of a bean protein concentrate (BPC) and a whole cooked bean flour (WCB) on body composition, glucose metabolism and energy expenditure in Wistar rats fed a control diet or high-fat diets with 5% sucrose in the drinking water. With this aim, rats were fed the experimental diets for 10 weeks. The results showed that consumption of either BPC or WCB reduced weight gain and body fat despite the consumption of a high-fat diet. This change was associated with a significant increase in energy expenditure and the capacity to adapt fuel oxidation to fuel availability. As a result, rats fed a bean-based diet had lower circulating glucose and insulin concentrations and normal glucose tolerance, which was associated with decreased expression of lipogenic genes in the liver. These results suggest that the type of protein and bioactive compounds particularly phenolic and flavonoid compounds present in BPC are suitable to improve the formulations used in dietary strategies for subjects with obesity or type 2 diabetes. The addition of legumes to the diet of subjects with insulin resistance, including black beans, could improve their metabolic status.

Six months under uncontrolled relative humidity and room temperature changes technological characteristics and maintains the physicochemical and functional properties of carioca beans (Phaseolus vulgaris L.)

Carioca beans contribute to health maintenance around the world, and the evaluation of commercial postharvest storage (CPS) ensures their quality. This study aimed to evaluate the effect of CPS on technological, physicochemical and functional properties of carioca beans. Two genotypes (Pontal-PO and Madreperola-MP beans) were stored under CPS or controlled conditions and were evaluated after harvest and after three- and six-months storage. PO and MP hardened with time, but the cooking time did not differ. PO is darker than MP and both darkened over time. Storage time affected pH and acidity of the beans and MP presented better physicochemical properties than PO, with lower activity of peroxidase (p = 0.004) and polyphenoloxidase (p = 0.001) enzymes. Glycosylated kaempferol was suggested as a possible chemical marker to differentiate the aging of PO and MP beans. In conclusion, besides the technological differences, the storage was able to prevent physicochemical and functional alterations of beans.

The influence of chemical composition diversity in the cooking quality of Andean bean genotypes

Andean beans (Phaseolus vulgaris) chemical compositions and cooking characteristics contribute to a healthy diet. The objective of this study was to evaluate the influence of chemical composition on the cooking quality of 14 Andean beans genotypes with different seed coat colors. More specifically, water retention (WR), cooking time (CT), and solids released in the broth, were analysed. WR values ranged from 128.4% to 160.7% and CT ranged from 13.7 (BRS Embaixador) to 21.7 min (KID44). Andean beans showed variability in chemical composition, mainly starch content (39.43 g 100 g^-1, BRS Realce to 51.92 g 100 g^-1, LP15-04) and polymer composition. The profile of starch and interactions among minerals and chemical compounds influenced the cooking profiles than do the individual compounds. Andean beans traits of cooking, mainly CT, were influenced by their chemical composition; however they can be incorporated into diets without drastic changes in preparation methods.

Autoclaving and extrusion improve the functional properties and chemical composition of black bean carbohydrate extracts

Common beans (Phaseolus vulgaris L.) are rich in starch with a high content of amylose, which is associated with the production of retrograded and pregelatinized starch through thermal treatments. The purpose of this study was to evaluate the composition, morphology, thermal, functional, and physicochemical properties of carbohydrate extracts (CE) obtained from autoclaved (100 and 121 °C) and extruded (90, 105, and 120 °C) black beans. After evaluation of the functional properties, the CE from autoclaved beans at 100 °C for 30 min and 121 °C for 15 min 2×, and extruded beans at 120 °C and 10 rpm, were selected to continue the remaining analysis. Autoclaving treatments at 100 °C for 30 min and 121 °C for 15 min 2× showed a reduction of resistant starch by 14.4% and 26.6%, respectively, compared to dehulled raw bean CE. Meanwhile, extrusion showed a reduction in resistant starch of 54.2%. Autoclaving and extrusion treatments also decreased the dietary fiber content. Extrusion reduced almost entirely the content of α-galactooligosaccharides, in comparison to dehulled raw bean CE. The results showed differences in color and granule morphology. The onset, peak, and conclusion temperatures, transition temperature range, and enthalpy of autoclaved and extruded bean CE were lower than dehulled raw bean CE. The CE from autoclaved and extruded beans contain retrograded and pregelatinized starch, which could be incorporated in food products as a thickening agent for puddings, sauces, creams, or dairy products. PRACTICAL APPLICATION: Thermally treated black bean carbohydrate extracts are rich in starch, fiber, and protein. Because these extracts are already cooked, they can be added to products that do not require a thermal process such as puddings, sauces, creams, or dairy products, acting as a thickening agent.

Elucidating potential utilization of Portuguese common bean varieties in rice based processed foods

The present study was aimed at studying the physico-chemical and functional properties of 31 Portuguese common bean varieties. In addition, the whole bean flours (WBF) and starch isolates (SI) of three representative bean varieties and their rice: bean blends (70:30; 50:50) were assessed for amylose content, thermal and pasting properties in view of supplementation in rice based processed foods. Bean varieties showed significant differences in protein content (20.78-27.10%), fat content (1.16-2.18%), hydration capacity (95.90-149.30%), unhydrated seeds (4.00-40.00%), γ tocopherol (3.20-98.05 mg/100 g fat), δ tocopherol (0.06-4.72 mg/100 g fat) and pasting behavior. Amylose content of WBF (11.4-20.2%) was significantly lower than rice flour (23.51%) whereas SI of beans (40.00-47.26%) had significantly higher amylose content than SI of rice (28.13%). DSC results showed that WBF (11.4-20.2 °C) had significantly broader and lower gelatinization temperature range (∆Tr) than corresponding SI (20.9-23.1 °C). WBF had significantly lower pasting viscosity due to low starch content and compositional matrix effect as compared to SI. Setback viscosities of WBF and rice: bean blends was lower than rice flour. Low setback viscosities of rice:bean blends may be used to prevent syneresis and stabilizing the quality of frozen foods in rice based processed foods.

Prediction of canned black bean texture (Phaseolus vulgaris L.) from intact dry seeds using visible/near infrared spectroscopy and hyperspectral imaging data

BACKGROUND

Texture is a major quality parameter for the acceptability of canned whole beans. Prior knowledge of this quality trait before processing would be useful to guide variety development by bean breeders and optimize handling protocols by processors. The objective of this study was to evaluate and compare the predictive power of visible and near infrared reflectance spectroscopy (visible/NIRS, 400-2498 nm) and hyperspectral imaging (HYPERS, 400-1000 nm) techniques for predicting texture of canned black beans from intact dry seeds. Black beans were grown in Michigan (USA) over three field seasons. The samples exhibited phenotypic variability for canned bean texture due to genetic variability and processing practice. Spectral preprocessing methods (i.e. smoothing, first and second derivatives, continuous wavelet transform, and two-band ratios), coupled with a feature selection method, were tested for optimizing the prediction accuracy in both techniques based on partial least squares regression (PLSR) models.

RESULTS

Visible/NIRS and HYPERS were effective in predicting texture of canned beans using intact dry seeds, as indicated by their correlation coefficients for prediction (R_pred ) and standard errors of prediction (SEP). Visible/NIRS was superior (R_pred = 0.546-0.923, SEP = 7.5-1.9 kg 100 g^-1 ) to HYPERS (R_pred = 0.401-0.883, SEP = 7.6-2.4 kg 100 g^-1 ), which is likely due to the wider wavelength range collected in visible/NIRS. However, a significant improvement was reached in both techniques when the two-band ratios preprocessing method was applied to the data, reducing SEP by at least 10.4% and 16.2% for visible/NIRS and HYPERS, respectively. Moreover, results from using the combination of the three-season data sets based on the two-band ratios showed that visible/NIRS (R_pred = 0.886, SEP = 4.0 kg 100 g^-1 ) and HYPERS (R_pred = 0.844, SEP = 4.6 kg 100 g^-1 ) models were consistently successful in predicting texture over a wide range of measurements.

CONCLUSION

Visible/NIRS and HYPERS have great potential for predicting the texture of canned beans; the robustness of the models is impacted by genotypic diversity, planting year and phenotypic variability for canned bean texture used for model building, and hence, robust models can be built based on data sets with high phenotypic diversity in textural properties, and periodically maintained and updated with new data. © 2017 Society of Chemical Industry.

Preparation and Characterization of Proteinaceous Films from Seven Mexican Common Beans (Phaseolus vulgaris L.)

Bean protein concentrate (BPC) as a protein source from seven varieties of Mexican common beans (alubia, flor de mayo, garbancillo, peruano, pinto, mantequilla, and negro) was utilized for formulating edible films (EF). EF were prepared with BPC (3% w/w) and glycerol as a plasticizer by the casting method; their thickness, water content, soluble matter, protein solubility, color, puncture strength, elongation, water vapor permeability (WVP), and chemical properties (Fourier transform infrared, FTIR, and spectroscopy) were evaluated. Tested EF had an average thickness of 0.045±0.001 mm. Good stability was observed since the studied polymers did not exceed 35% of the total soluble matter while protein solubilities were not greater than 3%. EF made from peruano bean protein presented a lower value of total matter solubility (25.38±2.24%) than the other tested EF. A low value of WVP (2.06±0.25×10-10 g m/Pa s m2) was observed in films from negro bean protein, while EF from flor de mayo bean protein exhibited the highest values of puncture strength (17.35±0.82 MPa) and elongation (38.21±0.64%). Most bean protein EF had reddish or brownish color; however, films from alubia and peruano bean proteins displayed light yellowish colors. FTIR spectra of EF revealed that glycerol did not react with the studied bean proteins through covalent bonds.