Carioca Bean Research Articles

Extrusion of Rice, Bean and Corn Starches: Extrudate Structure and Molecular Changes in Amylose and Amylopectin.

The objective of this study was to evaluate the effects of starch source and amylose content on the expansion ratio, density, and texture of expanded extrudates, as well as to investigate the structural and molecular changes that occur in starch granules as a function of extrusion. The starches employed were rice starches (8%, 20%, and 32% amylose), carioca bean starch (35% amylose), and Hylon V® corn starch (55% amylose). The extrudates from rice starches containing 20% and 32% amylose exhibited the highest expansion ratio, while, extrudates from Hylon V® corn starch containing 55% amylose exhibited the lowest expansion ratio. The hardness values of the extrudates with 55% amylose were twice those of the extrudates with 20%, 32%, and 35% amylose. An additional finding was that although the amylopectin promoted the expansion of the gelatinized starch matrix, it failed to strengthen and sustain the walls of the extrudate bubbles during expansion.

Technological quality of grains of common beans selected genotypes from the carioca group

Common bean variety improvement programs focus on productivity increase as their main goal. However, some characteristics related to technological quality must also be analyzed in order to assure that new recommended cultivars satisfy key commercial standards, related to consumer acceptance. This study evaluated the technological quality of seeds from different ‘carioca’ bean genotypes. We tested seeds from 25 bean genotypes, selected by the State Consortium for Research on Common Bean Improvement (including EMBRAPA, UFLA, UFV and EPAMIG) for the VCU assay of the carioca variety, including 21 new lines and 4 commercial cultivars, used as controls. The experiment was arranged in a randomized complete block design with three replications. We assessed the following traits: seed shape, seed constriction, 1000-seed weight, percentage of hard seeds, soluble solids content, cooking time, seed coat percentage, and hydration capacity. According to our results, the cultivars that met the commercial standards for seed shape and constriction were EMB14, CNFC 10432, CNFC 10408, EMB4, P-18163, Pérola and BRSMG Madrepérola. Genotypes MAIV-18259, VC-20, VC-23, RCII-219, CVIII-2, EMB4, MAIV-15204, CVIII-5, and BRSMG Majestoso had 1000-seed weight within carioca bean commercial standards (a minimum of 23g per 100 seeds). Most genotypes had no hard seeds. Lines CNFC 10408, MAIV-18259 and P-18163 had the highest soluble solids content. Twenty genotypes had cooking times below the maximum required by commercial standard, with lines EMB9, EMB4, MAIV-18524, CNFC 11965, VC-17, and CNFC 10432 having the shortest cooking time. Lines CNFC 11965, EMB4, EMB14, and CNFC 10432 also had the shortest time to soaking.

Phenolic compound in beans as protection against mycotoxins

Phenolic compounds, their inhibitory activity against fungal amylase and the occurrence of aflatoxins were determined in edible beans. The free, conjugated and bounded phenolic compounds and their phenolic acid profiles were determined in ten bean varieties. A method for aflatoxin B1, B2, G1 and G2 determination and confirmation by LC–MS/MS was validated. The red and carioca beans presented the highest total phenolic content (1.8 and 1.2mg.g−1, respectively); the fradinho and white beans the lowest (0.18 and 0.19mg.g−1, respectively). In the free and conjugated forms, chlorogenic acid was present in 60% of the samples, while in the bounded phenolic, ferulic acid was in 90% of the samples. The phenolic extracts were able to inhibit fungal amylase, and the PCA analysis confirmed that the relation between the chlorogenic and gallic acids is important to this effect. The absence of aflatoxins in samples confirm the protector effects of these phenolic compounds.

English

The recommendation of bean cultivars and the use of appropriate storage techniques allow the quality characteristics of these grains to be preserved for human consumption. The aim of this study was to characterize the effects of storage on three cultivars of the common carioca bean in raw form and to determine the relationships between storage time and technological quality parameters involved in the darkening and hardening of grains, the chemical composition of the beans and the presence of secondary metabolites. The experiment followed a completely randomized design (CRD) with a full factorial scheme consisting of two factors: bean cultivars, with three levels and storage time, with five levels. The color parameters and the storage times significantly differed between the cultivars. The cooking time, when compared to the water absorption index, indicated that the cultivars had, on average, a high percentage of moisture (>95%) and an average cooking time of 17 min., this applies to the control, while values increase during the storage time. Storage under ambient conditions led to a reduction in grain brightness parameters, characterized by darkening and hardening; no reduction in protein and mineral content; and an increase in iron, phosphorous, tannin, and phytic acid contents at 180 days. Key words: Cooking time, grain color, multivariate analysis, phaseolus vulgaris.

The use of statistical methods for censored data to evaluate the activity concentration of Pb-210 in beans (Phaseolus vulgaris L.)

A survey of 210Pb activity concentration, one of the major internal natural radiation sources to man, has been carried in the most common species of beans (Phaseolus vulgaris L.) grown and consumed in Brazil. The representative bean types chosen, Carioca beans and black type sown in the Brazilian Midwestern and Southern regions, have been collected in this study and 210Pb determined by liquid scintillation spectrometry after separation with chromatographic extraction using Sr-resin. Available values in data set of radioactivity in Brazil (GEORAD) on the 210Pb activity concentration in black beans grown in Southeastern region have been added to the results of this study with the purpose of to amplify the population considered. Concerning the multiple detection limits and due to the high level of censored observations, a robust semi-parametric statistical method called regression on order statistics (ROS) has been employed to provide a reference value of the 210Pb in Brazilian beans, which amounted to 41 mBq kg−1 fresh wt. The results suggest that the 210Pb activity concentration in carioca beans is lower than in black beans. Also evaluated was the 210Pb activity concentration in vegetable component of a typical diet, which displays lower values than those shown in the literature for food consumed in Europe.

Digested protein isolate from fresh and stored Carioca beans reduced markers of atherosclerosis in oxidized LDL-induced THP-1 macrophages

Oxidized LDL (ox-LDL) and its interaction with lectin type ox-LDL receptor (LOX-1) determine atherosclerosis progression. The potential of peptides from digested protein isolate (DPI) derived from fresh and stored Carioca bean (Phaseolus vulgaris L.) to prevent ox-LDL induced inflammation in human THP-1 macrophage-like cells was examined here. BRS Pontal (PO) and BRSMG Madreperola (MP) fresh and stored for 6 months were cooked, and protein isolates were digested by pepsin–pancreatin. Peptides from stored Carioca beans decreased prostaglandin E-2 (PGE-2) (from 17.7 to 47%) and tumour necrosis factor-α (TNF-α) (12.3 to 82%). Stored MP (0.01 mg/mL) inhibited reactive oxygen species (ROS). LOX-1 and matrix metalloproteinase-9 (MMP-9) expression were reduced by peptides from all beans. Stored PO and MP digested protein isolates reduced expression of 10 cytokines related to atherosclerosis process. Peptides from Carioca beans presented anti-atherosclerotic properties comparable to simvastatin, which were related to inhibition of LOX-1, MMP-9 and ICAM-1.

Studies of Cream Seeded Carioca Beans (Phaseolus vulgaris L.) from a Rwandan Efficacy Trial: In Vitro and In Vivo (including effects on intestinal microbiome) Screening Tools Reflect Human Studies and Predict Beneficial Results from Iron Biofortified Beans

Iron (Fe) deficiency is a highly prevalent micronutrient insufficiency predominantly caused by a lack of bioavailable Fe from the diet. The consumption of beans as a major food crop in some populations suffering from Fe deficiency is relatively high. Therefore, our objective was to determine whether a biofortified variety of cream seeded carioca bean (Phaseolus vulgaris L.) could provide more bioavailable‐Fe than a standard variety using in‐vivo (broiler chicken, Gallus gallus) and in‐vitro (Caco‐2 cell) models. Studies were conducted under conditions designed to mimic the actual human feeding protocol. Two carioca‐beans, a standard (G4825; 58μg Fe/g) and a biofortified (SMC; 106μg Fe/g), were utilized. Diets were formulated to meet the nutrient requirements of Gallus gallus except for Fe (33.7 and 48.7μg Fe/g, standard and biofortified diets, respectively). In‐vitro observations indicated that more bioavailable‐ Fe was present in the biofortified beans and diet (P<0.05). In‐vivo, improvements in Fe‐status were observed in the biofortified bean treatment, as indicated by the increased total‐body‐Hemoglobin‐Fe, and hepatic Fe‐concentration (P<0.05). Also, DMT‐1 mRNA expression was increased in the standard bean treatment (P<0.05), indicating an upregulation of absorption to compensate for less bioavailable‐ Fe. These results demonstrate that the biofortified beans provided more bioavailable Fe; however, the in vitro results revealed that ferritin formation values were relatively low. Such observations are indicative of the presence of high levels of polyphenols and phytate that inhibit Fe absorption. Indeed, we identified higher levels of phytate and quercetin 3–glucoside in the Fe biofortified bean variety. Our results indicate that the biofortified bean line was able to moderately improve Fe‐status, and that concurrent increase in the concentration of phytate and polyphenols in beans may limit the benefit of increased Fe‐concentration. Therefore, specific targeting of such compounds during the breeding process may yield improved dietary Fe‐bioavailability. Our findings are in agreement with the human efficacy trial that demonstrated that the biofortified carioca beans improved the Fe‐status of Rwandan women. We suggest the utilization of these in vitro and in vivo screening tools to guide studies aimed to develop and evaluate biofortified staple food crops. This approach has the potential to more effectively utilize research funds and provides a means to monitor the nutritional quality of the Fe‐biofortified crops once released to farmers. In addition, cecal contents analysis indicated that the lower Fe status in the standard bean treatment group had altered the composition, structure and function of the intestinal microbiome.

Postharvest storage of Carioca bean (Phaseolus vulgaris L.) did not impair inhibition of inflammation in lipopolysaccharide-induced human THP-1 macrophage-like cells

Storage can affect the nutritional quality of common bean (Phaseolus vulgaris), but little is known about the postharvest effect of storage on inflammation. The aim of this work was to evaluate, in vitro, the effect of postharvest storage-time on inflammation by Carioca beans, Madreperola (MP) and Pontal (PO), stored (0, 3 and 6 months), cooked and subjected to pepsin-pancreatin simulated gastrointestinal digestion. Anti-inflammatory potential was investigated in human THP-1 macrophage-like cells. Commercial storage time did not affect protein concentration, degree of hydrolysis, hydropathicity or antioxidant capacity. All PO hydrolysates reduced tumour necrosis factor-α (TNF- α) (31% on average). MP hydrolysates decreased interleukin 1β (IL-1β) (PO 0: 0.1 mg/mL, 20.7%; PO 0 and 6: 5 mg/mL, 24.8 and 48.2%, respectively) and prostaglandin E-2 (PGE-2) (PO 0: all concentrations, 18% on average; PO 6: 0.1 mg/mL, 18.6%). Carioca beans inhibited inflammation and commercial storage time did not impair physicochemical or biological properties.

Do enzymatic or non-enzymatic pathways drive the postharvest darkening phenomenon in carioca bean tegument?

Four genotypes of carioca bean were accelerate aged (40 °C/75% relative humidity) and evaluated to determine if differences in postharvest darkening trait was an enzymatic or non-enzymatic process. Chromaticity a* was the colour parameter with major alterations, and increase in chromaticity b* often masked the reddish of tegument. Peroxidase activity was not detected. Polyphenoloxidase remained active along the storage time, but its activity was higher in the lighter genotypes. Flavonoid, proanthocyanidin and total phenol content were much higher in darker genotypes, although just this last component presented significant alterations. Genotypes showed different susceptibilities to the darkening independent of phenolic content. Results of principal response curves analyse suggested different pathways for the darkening process: darkening in lighter genotypes seem to be mostly due to polyphenoloxidase activity while in dark ones there are the combination of enzymatic and non-enzymatic oxidation.

Genetic progress and potential of common bean families obtained by recurrent selection

Abstract The objective of this study was to estimate the genetic gain of two recurrent selection cycles in common bean breeding and identify families with the potential to generate superior lines. The base population, cycle zero (C0), was obtained by combining 20 carioca bean parents, populations with favorable phenotypes for several agronomically important traits. The parents were recombined in a circulant diallel scheme, in which each parent participated in two crosses, generating 20 populations. From these populations, families were derived and evaluated for three seasons in the generations F2:3, F2:4 and F2:5. The same procedures of recombination and evaluation in C0 were performed in cycle one (CI). The genetic gain for yield, estimated from the simultaneous evaluation of the 40 best families of each cycle, was 8.6%. Families with potential to generate superior lines to cultivar Pérola were identified, especially among the CI families.

Analyses of technological and biochemical parameters related to the HTC phenomenon in carioca bean genotypes by the use of PCA

Carioca beans are subjected to the hard-to-cook phenomena (HTC), which results in loss of technological and sensorial qualities. To better elucidate this postharvest hardening process, changes in technological and biochemical properties of grains during storage at 40 °C and 75% relative humidity were investigated, and the results were analyzed using Principal Component Analysis (PCA). Results showed that the hardening process occurs at different intensity for each genotype, and those more susceptible to HTC presented higher water absorption index (WAI) and peroxidase activity. During the storage period, oxidoreductases remained active and total phenol content increased for all genotypes. PCA explained 92.2% of total variance and grouped hardness, cooking time and WAI on PC1 (67.8%) and peroxidase activity and total phenol content on PC2 (24.4%). PCA showed that the technological parameter more related to the HTC is WAI and that hardness observed in genotypes during storage cannot be attributed to changes in the total phenol content nor to oxidorreductase activities.

Studies of Cream Seeded Carioca Beans (Phaseolus vulgaris L.) from a Rwandan Efficacy Trial: In Vitro and In Vivo Screening Tools Reflect Human Studies and Predict Beneficial Results from Iron Biofortified Beans.

Iron (Fe) deficiency is a highly prevalent micronutrient insufficiency predominantly caused by a lack of bioavailable Fe from the diet. The consumption of beans as a major food crop in some populations suffering from Fe deficiency is relatively high. Therefore, our objective was to determine whether a biofortified variety of cream seeded carioca bean (Phaseolus vulgaris L.) could provide more bioavailable-Fe than a standard variety using in-vivo (broiler chicken, Gallus gallus) and in-vitro (Caco-2 cell) models. Studies were conducted under conditions designed to mimic the actual human feeding protocol. Two carioca-beans, a standard (G4825; 58μg Fe/g) and a biofortified (SMC; 106μg Fe/g), were utilized. Diets were formulated to meet the nutrient requirements of Gallus gallus except for Fe (33.7 and 48.7μg Fe/g, standard and biofortified diets, respectively). In-vitro observations indicated that more bioavailable-Fe was present in the biofortified beans and diet (P<0.05). In-vivo, improvements in Fe-status were observed in the biofortified bean treatment, as indicated by the increased total-body-Hemoglobin-Fe, and hepatic Fe-concentration (P<0.05). Also, DMT-1 mRNA-expression was increased in the standard bean treatment (P<0.05), indicating an upregulation of absorption to compensate for less bioavailable-Fe. These results demonstrate that the biofortified beans provided more bioavailable Fe; however, the in vitro results revealed that ferritin formation values were relatively low. Such observations are indicative of the presence of high levels of polyphenols and phytate that inhibit Fe absorption. Indeed, we identified higher levels of phytate and quercetin 3–glucoside in the Fe biofortified bean variety. Our results indicate that the biofortified bean line was able to moderately improve Fe-status, and that concurrent increase in the concentration of phytate and polyphenols in beans may limit the benefit of increased Fe-concentration. Therefore, specific targeting of such compounds during the breeding process may yield improved dietary Fe-bioavailability. Our findings are in agreement with the human efficacy trial that demonstrated that the biofortified carioca beans improved the Fe-status of Rwandan women. We suggest the utilization of these in vitro and in vivo screening tools to guide studies aimed to develop and evaluate biofortified staple food crops. This approach has the potential to more effectively utilize research funds and provides a means to monitor the nutritional quality of the Fe-biofortified crops once released to farmers.

Effects of acetylation and acetylation–hydroxypropylation (dual-modification) on the properties of starch from Carioca bean (Phaseolus vulgaris L.)

Carioca bean is an important product of Brazil and its major components are protein and starch. In its native form, starch has some technological constraints and modifications can improve its properties. Acetylation facilitates water percolation in amorphous regions, and hydroxypropylation improves water penetration. The aim of this study was to evaluate the effects of acetylation and dual-modification on the properties of starch from Carioca beans (Phaseolus vulgaris L.). The native starch was modified by acetylation and dual-modification (acetylation and hydroxypropylation) and then analyzed by SEM, X-ray diffractometry, FT-IR spectroscopy, DSC, TG, pasting properties, and syneresis. The modifications did not change the shape, size, and surface of the starch granules, although they affected their amorphous regions. FT-IR bands presented a peak at 1,732 cm−1, which was assigned to acetylation, and another at 2,974 cm−1, which was due to hydroxypropylation. TG–DTA curves showed typical behavior of starches with three mass losses. DSC curves showed an increase in the enthalpy to gelatinisation for sample (b) and a reduction for sample (c). RVA curves showed a reduction in the initial temperature, an increase in peak viscosity, and breakdown and setback after modifications. The acetylated starch showed higher freeze–thaw stability; however, syneresis was higher for the dual-modified starch.

Influence of Storage on Darkening and Hardening of Slow- and Regular-Darkening Carioca Bean (Phaseolus vulgaris L.) Genotypes

New carioca bean cultivars are being introduced into the market necessitating their evaluation under trade conditions, which often require storage under ambient conditions. We therefore evaluated the darkening and hardening processes of six carioca bean genotypes each representing regular and slow darkening trait during storage under ambient conditions for five months to elucidate their relationship as a breeding strategy. Storage time adversely affected color characteristics (L*, a*, b*, C* and ΔE) depending on bean genotype, whereas hardness and resistance to cooking increased during storage independent of the lignification process. Bean darkening and hardening occurred during storage at different intensities in each genotype and were not always correlated. BRSMG-Madrepérola, a slow darkening genotype, was unaffected (resistant to storage conditions), whereas BRS-Pontal with regular tegument darkening, was highly susceptible to storage conditions reflected in extended cooking time and darkening (low L* values). Principal component and cluster analyses on 8 constituents analyzed in this study demonstrate the difference in color characteristics, cooking time and hardness as major factors in segregating the bean genotypes. Seed coat color is an important but inappropriate single parameter for predicting the resistance to cooking or hardness induced by storage of carioca beans under ambient conditions. Development of carioca bean genotypes resistant to storage conditions is essential in reducing food losses during postharvest.

Effects of nitrogen-modified atmosphere storage on physical, chemical and technological properties of Carioca bean

When stored under inappropriate conditions, the carioca bean grains are affected by hardening defect accompanied by the coat colour change that occurs as a function of phenolic compounds oxidation. The aim of this study was to evaluate the effects of nitrogen-modified atmosphere storage on coat colour preservation and development of hard-to-cook defect in Carioca beans stored for 360 days. Storage in the nitrogen-modified atmosphere preserved 5.80 g kg -1 protein, 2.70 g kg -1 fat, a 9.54 coat colour difference index ( Δ E*), 4.89 g kg -1 gallic acid (phenolic content), a 540-second cooking time and a hardness of 19.09 N grain -1 when compared to grain stored in the normal atmosphere (oxygen) for 360 days. Moreover, the storage in a nitrogen-modified atmosphere preserved the hydration coefficient and the electrical conductivity of carioca bean and slows the development of the HTC defect, at least for 360 days storage. This storage system also reduces the cellular stresses caused by storage in the normal atmosphere at 25°C.

Physical characteristics of extrudates from corn flour and dehulled carioca bean flour blend

Extruded products were prepared from a corn flour and dehulled carioca bean (Phaseolus vulgaris, L.) flour blend using a single-screw extruder. A central composite rotate design was used to evaluate the effects of extrusion process variables: screw speed (318.9–392.9 rpm), feed moisture (10.9–21.0 g/100 g) and bean flour level (4.8–55.2 g/100 g) on the specific mechanical energy (SME), sectional expansion index (SEI), longitudinal expansion index (LEI), volumetric expansion index (VEI) and density (D) of the extrudates. The instrumental texture was also analyzed. The independent variables had significant effects on the physical properties (SEI, VEI and density) of extrudates, with the exception of SME and LEI. SEI increased with increasing screw speed, but a higher moisture and bean flour content resulted in decreasing SEI and VEI. The increase of moisture and bean flour increased the density of extrudates. According to texture analysis, some treatments with 30 and 45 g/100 g bean flour did not show significant differences when compared to commercial brand snacks. However, when combined with higher moisture content (≥19 g/100 g) and lower screw speed (≤333 rpm), the results of the expanded product were not satisfactory.

Aplicação de extrato etanólico de própolis no crescimento e produtividade do feijoeiro comum

A própolis é uma substância muito utilizada em várias áreas da ciência, porém, os efeitos da sua aplicação em culturas anuais ainda são desconhecidos. Diante disto, objetivou-se, com este trabalho, verificar o efeito da aplicação de extrato etanólico de própolis (EEP) sobre a severidade da antracnose, o crescimento e a produtividade do feijoeiro carioca, cultivar IPR 139. Foram conduzidos dois experimentos no período de outubro de 2010 a janeiro de 2011. O delineamento experimental dos experimentos foi o de blocos ao acaso, com cinco repetições, realizando-se três aplicações de EEP nas concentrações: 0; 1; 2; 3 e 4%, quinzenalmente, a partir de 25 dias após a emergência (DAE). O EEP foi preparado com 10% de própolis bruta (originária do litoral paranaense) e 90% de álcool, a 96 ºGL. A altura das plantas, o número de folhas e a área foliar não foram alterados. O EEP na concentração de 4% reduziu a severidade da antracnose em até 63%, aumentou os teores foliares de nitrogênio (N), magnésio (Mg), ferro (Fe), a área foliar/folha e produtividade em até 33%. A redução da severidade da antracnose, obtida com a aplicação do EEP, aumentou a produtividade do feijoeiro.

Genetic control and estimation of genetic parameters for seed-coat darkening of carioca beans.

The maintenance of the light color of the grains of carioca beans is a requirement for the development of new cultivars of common beans because it enables the storage of grains for long periods so that they may be traded at a proper opportunity. Crosses of cultivar BRSMG Madrepérola, which presents slow grain darkening, were made to 10 elite lines presenting normal darkening to obtain information about the genetic control of the trait and estimates of phenotypic and genotypic parameters. Progenies at the tegument generations F3 and F4 and their parents were evaluated at the locations of Santo Antônio de Goiás and Ponta Grossa at 71, 106, and 155 days of storage for seed-coat darkening using a rank of scores ranging from 1 (very light colored grains) to 5 (very dark colored grains). Genotypic and phenotypic variances and broad-sense heritabilities were estimated for each population. The segregation ratios were subjected to the chi-square test to establish the genetic control. Some populations did not present consistent patterns of genetic control, while others presented monogenic or double-recessive digenic segregation, indicating that the trait is controlled by few genes. Six segregant populations were identified with both low means for darkening and high expected gain under selection. Despite the strong environmental influence on the expression of the traits and the occurrence of the genotype by environment interaction, the estimates of genotypic and phenotypic parameters indicate the possibility of successful selection to develop lines with slow seed-coat darkening.

Productivity and nodulation of promising lineages of the Carioca bean group inoculated with Rhizobium tropici or supplemented with nitrogen fertilizer

O trabalho teve por objetivo avaliar a nodulacao e produtividade de linhagens de feijoeiro do grupo Carioca quando submetidas a inoculacao com Rhizobium tropici ou a adubacao nitrogenada. Os experimentos foram conduzidos em Dourados, MS, nos anos de 2008 (experimento 1) e 2009 (experimento 2). O delineamento experimental utilizado foi o de blocos ao acaso, com tres repeticoes, em um esquema fatorial 2x14, em que os fatores foram as duas formas de fornecimento de nitrogenio (N-mineral e inoculacao com rizobio) e 14 diferentes linhagens de feijoeiro, em cada experimento. As sementes foram inoculadas com uma mistura das estirpes CIAT 899 (SEMIA 4077) e PRF 81 (SEMIA 4080) de R. tropici . Para a maioria das linhagens avaliadas, as produtividades de graos do feijoeiro foram similares entre as plantas inoculadas com R. tropici e aquelas adubadas com 80 kg ha-1 de N. O comportamento diferenciado de algumas linhagens quanto a nodulacao e parâmetros fitotecnicos demonstra que a fonte de fornecimento de N (inoculacao de rizobio ou adubacao nitrogenada) nos estudos de melhoramento genetico para selecao de cultivares de feijoeiro pode influenciar diretamente no seu potencial produtivo.

Influence of the environment in 40K concentration in Brazilian common beans

The consumption of beans constitutes an important dietary habit in many Latin American, Asian and African countries. Carioca beans and the black type stand out among the many consumed common beans in Brazil. 40K was used as a natural radiotracer to evaluate the influence of the season growing and the bean type in the potassium content into grain. The activity concentrations of 40K and 137Cs were evaluated on samples of beans by γ-ray spectrometry. 137Cs was less than 1.3 Bq kg −1. The highest potassium content in the grain were observed in the dry and winter seasons. The black beans showed higher potassium content than the carioca type. The potassium levels were compared with that of beans grown and consumed in other regions of the world. A method to estimate the bean consumption rates in Brazil independently of the location of the meal is proposed. The ingestion of common beans was estimated in 14.6 kg year−1 per person. The two regions with the highest consumption are the Southeast (19.2 kg year−1) and the Middle West (18.7 kg year−1), whose account for about 60 % of the intake of common beans is related to consumption out home.