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Summary: With the growing demand for convenient and shelf‐stable canned beans, understanding the changes in starch digestibility due to retort processing is crucial for optimising nutritional quality and enhancing consumer health. The present study investigated the impact of retort processing, specifically container type and agitation, on the digestibility of black bean starch. Retort pouches exhibited a more rapid heat transfer rate to the enclosed product than cans, which reduced the overall processing duration. Also, the processing time to achieve a Fo = 6 of Clostridium botulinum was almost 2.5 min (pouches) and 3.2 min (cans) faster for the oscillating than the static mode. The in vitro digestibility data revealed that the retort processing of black beans led to an increase in rapidly digestible starch (RDS) from 10.51% to 32.11%. However, slowly digestible starch (SDS) decreased from 15.67% to 7.89%, and resistant starch (RS) decreased from 47.91% to 11.86%, regardless of the container type and motion involved. Processing enhanced starch digestibility in all the combinations of container and motions; nevertheless, black beans in pouches with oscillatory motion still contain a relatively significant amount of SDS and RS than the other combinations. These findings have important implications for the food industry in optimising processing techniques and packaging strategies to preserve the nutritional value of black beans. The findings of this study can have practical implications for food producers engaged in the retort processing of foods contained in pouches and cans. The investigation will provide insights into how the process of retort sterilisation affects digestibility, including slowly digestible starch and resistant starch of different types of starch. [ABSTRACT FROM AUTHOR]

The use of arbuscular mycorrhizal fungi (AMF) as biofertilizers has proven successful in boosting the yield and nutritional quality of a variety of crops. AMF associate with plant roots and exchange soil nutrients for photosynthetically derived C in the form of sugars and lipids. Past research has shown that not all AMF species are equal in their benefit to nutrient uptake and crop health, and that the most beneficial AMF species appear to vary by host species. Although an important human food staple, especially in developing regions where nutrient deficiency is a prevalent threat to public health, little work has been done to test the effectiveness of AMF in enhancing the nutritional quality of common bean (Phaseolus vulgaris L.). Therefore, our objective was to determine the most beneficial AMF species for inoculation of this important crop. We inoculated black beans (Phaseolus vulgaris black turtle beans) with eight individual AMF species and one mixed species inoculum in an outdoor pot trial over 3 months and assessed the extent to which they altered yield, mineral nutrient and anthocyanin concentration of seeds and leaf tissues. Despite seeing no yield effects from inoculation, we found that across treatments percent root length colonized by AMF was positively correlated with plant tissue P, Cu, and Zn concentration. Underlying these broad benefits, seeds from plants inoculated with three AMF species, Claroideoglomus claroideum (+15%), Funneliformis mosseae (+13%), and Gigaspora rosea (+11%) had higher P concentration than non‐mycorrhizal plants. C. claroideum also increased seed potassium (K) and copper (Cu), as well as leaf aluminum (Al) concentration making it a promising candidate to further test the benefit of individual AMF species on black bean growth in field trials. [ABSTRACT FROM AUTHOR]

Background and Objectives: Particle size and shape can influence inherent flour properties and eventually the quality of the finished food product. The objective of this study was to determine the effect of mill type on the physical and flow properties of selected particle size fractions of black bean flour. Findings: Particle shape differed with mill type and particle size. Disc mill and stone mill produced flour particles with lower circularity and greater elongation than did hammer mill, cyclone mill, and centrifugal mill. Greater particle elongation with a stone mill and disc mill is attributed to compression/shear size‐reduction forces applied to the particles trapped between the rotating/nonrotating stones or discs. Particle circularity increased with an increased particle size, which was reflected by a strong positive correlation between circularity and particle size (r =.93, n = 5) while elongation value was negatively correlated with average minimum particle size (r = −.90, n = 5). Particle circularity had a negative correlation of r = −.93, n = 30; r = −.81, n = 30; r ≈ −.95, n = 30; r = −.94, n = 30 with L*, angle of repose, angle of slide, and compact bulk density, respectively. Conclusions: Mill type and particle size interaction significantly affected the physical and flow properties of selected particle size fractions of black bean flour. The results indicate that the large black bean particles were more circular and compact and less convex and elongated compared with small particles. Significance and Novelty: These findings indicate that mill type affects not only particle size but also particle shape, both of which can affect the flow and functional processing properties of black bean flour. [ABSTRACT FROM AUTHOR]

Summary: Radio frequency (RF) heating has been considered an alternative to conventional postharvest disinfestation methods in stored agricultural products. RF treatments at pilot scale (12 kW, 27.12 MHz) were applied in black beans (batches of 10 and 20 kg), until reach the target temperature for weevil mortality (50 °C). Temperature was held by 1 min, and then beans were cooled by forced air. During the protocol, the temperatures were followed by thermal images. For the 10 kg batch, the average heating time was 2.72 min, while for the 20 kg batch, only 1.29 min were required to reach the target temperature of 50 °C. This reduction in heating time is due to dielectric heating provides rapid and volumetric heating. Average cooling time was 14.75 and 26.75 min for batches of 10 and 20 kg respectively. The heating uniformity index values (λ) were close to zero (0.025 for 10 kg batch and 0.023 for 20 kg), indicating even heating. Water absorption capacity, density and viability of beans were not affected by the RF treatments (P > 0.05). Due to volumetric heating, better results were obtained for 20 kg batch, demonstrating the feasibility of RF technology for disinfestation purposes in relatively large batches of black beans. [ABSTRACT FROM AUTHOR]

Background and objectives: Phenolic compounds are known to form complexes with proteins which cause changes in the structural, functional, and nutritional properties of both compounds. The objective of this study was to evaluate the effect of removing soluble phenolic compounds from whole bean and cotyledon flours on the functional and rheological properties of black bean protein isolates. Findings: Protein isolates from cotyledon flour free of soluble phenolics (CFPInoP) had significantly lower (p <.05) ash content and significantly higher (p <.05) protein content and brightness compared with other protein isolates. CFPInoP had significantly greater (p <.05) wettability, dispersibility, foaming capacity (FC), foaming stability, emulsion capacity (EC), and emulsion stability (ES) than other protein isolates. Water‐binding capacity (WBC) was significantly greater (p <.05) for protein isolates with high phenolic content. Storage modulus and loss modulus were lower for protein gels made from protein isolates containing phenolic compounds compared with those made from protein isolates without soluble phenolic compounds. Conclusions: Removal of soluble phenolic compounds improved the functional and rheological properties of black bean protein isolates. Significance and novelty: As potential food ingredients, the functional properties of black bean protein isolates without soluble phenolic compounds were better compared with protein isolates with soluble phenolic compounds. [ABSTRACT FROM AUTHOR]

Background and objectives: Dry bean milling has attracted interest due to the increased need for nonwheat ingredients available for food applications. The objective of this study was to examine the physical and flow properties of black bean flour produced using a variety of laboratory mills and mill settings. Findings: Flour from mills which utilized screens (cyclone mill, centrifugal mill, and hammer mill) showed significantly different characteristics than flour from mills without a screen (disk mill and stone mill). Geometric mean size of flour particles was negatively correlated with starch damage (r = −.92), L* (r = −.94), angle of repose (r = −.94), and angle of slide (r = −.80 to −.90, depending on surface material) and positively correlated with moisture content (r =.72) and loose bulk density (r =.72). Finely ground flour resulted in particles that tended to be less circular and more elongated and had high angles of repose and slide. Conclusions: Milling method significantly affected (p <.05) physical and flow properties of black bean flour. Significance and novelty: These findings can be used by food processors in selecting a milling method that favors the production of black bean flour with the desired physical properties. [ABSTRACT FROM AUTHOR]

BACKGROUND: Various foods are known to have beneficial effects on health when consumed whole; however, there is a trend towards preparing foods from processed ingredients, and it remains unclear whether the benefits of the whole food are retained. The purpose of this study was therefore to examine whether different processing techniques affect the lowering of cholesterol and the vascular effects of black beans (Phaseolus vulgaris L.). RESULTS: Beans were prepared by overnight soaking and boiling – the standard method – and by micronization, extrusion, or dehulling and boiling, and they were then fine milled. Beans prepared by the standard method were also coarse milled. These five materials were incorporated into semi‐purified diets (30% wt/wt) and fed to spontaneously hypertensive rats for 4 weeks. Body weight, blood pressure, and aorta morphology were unaltered by the diets. Fasting total cholesterol was significantly reduced in rats fed micronized beans compared with extruded beans (both fine‐milled) or the bean‐free diet, while boiling combined with coarse milling lowered low‐density lipoprotein (LDL) cholesterol. The lack of cholesterol lowering in rats fed extruded bean compared to micronized was not explained by the amount or composition of dietary fiber or resistant starch. Differences in the polyphenolic profile as determined by high‐performance liquid chromatography (HPLC) were also unable to explain the variations in cholesterol‐lowering capacity. CONCLUSION: The present study demonstrates that processing of black beans alters the health effects observed with the whole pulse, and suggests that products prepared with processed ingredients will need to be tested empirically to establish whether the biological effects are maintained in vivo. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

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 ( Rpred) and standard errors of prediction (SEP). Visible/NIRS was superior ( Rpred = 0.546-0.923, SEP = 7.5-1.9 kg 100 g−1) to HYPERS ( Rpred = 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 ( Rpred = 0.886, SEP = 4.0 kg 100 g−1) and HYPERS ( Rpred = 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 [ABSTRACT FROM AUTHOR]

The effects of soaking, boiling, and steaming processes on the phenolic components and antioxidant activity of black beans were investigated. All processed beans exhibited significantly ( P < 0.05) lower antioxidant activities than raw beans in total phenolic content (TPC), DPPH free radical scavenging activity (DPPH), and oxygen radical absorbing capacity (ORAC). Steaming processes resulted in a greater retention of TPC and ORAC values than the boiling processes. Pressure boiling shortened processing time compared to regular boiling, resulted in insignificant differences in TPC, but significantly increased in ORAC as compared to the regular boiling method. Pressure steaming resulted in significant decreases in TPC, DPPH, while significantly increased in ORAC compared to regular steaming. Greater TPC, DPPH, and ORAC values were detected in boiling water than in the soaking and steaming water. Mass balance analysis showed that boiling caused more dry solid loss than steaming. All of these results indicated that processing methods significantly changed contents and activities of antioxidant components of black beans. Steam processing exhibited several advantages in appearance and texture of the cooked product, shortening processing time, and in greater retention of TPC and antioxidant activities. Steam processing may be used to develop high-quality health-promoting black bean products. [ABSTRACT FROM AUTHOR]

Previous studies have related the slow digestion properties of isolated starches with their amylose to amylopectin ratio as well as their molecular structure, and in the case of flours, with their accompanying components such as proteins and fibers; which are known to restrict, to different extents the starch digestion by amylolytic enzymes. However, the botanical origin as well as the internal architecture of native starch granules plays a significant role in these characteristics. Moreover, these features can be improved by using hydrothermal treatments, such as heat moisture treatment (HMT) and annealing (ANN), that promote changes to granular architecture, increase internal crystallite order and decrease the amount of amorphous zones. In this study, HMT and ANN treated starches from two bean varieties and a normal maize starch are analyzed in terms of thermal stability, assessed by differential scanning calorimetry, viscosity by rapid visco analysis and in vitro amylolysis. The HMT and ANN treatments promote lower hydrolysis when compared to native granules, due to new and/or improved molecular interactions between starch molecules, assessed by attenuated total reflectance‐fourier transform infra red spectroscopy; such interactions increase the amount of crystalline residues after digestion, which is related with lower water absorption during cooking, and enhanced thermal stability, despite the lower enthalpies in thermal treated starches (≈3 J g−1 in Black bean with HMT). Furthermore, the hydrolysis residues after 120 min of amylolysis present a higher ratio of crystalline regions, that improve with thermal treatments, this demonstrates that these processes increase the order of existing crystallites due to new molecular interactions among starch molecules. Thermal treatments heat moisture treatment (HMT) and annealing are applied to maize, black and bayo bean starches. When cooked and subject to amylolysis, their residues after 20 and 120 min are FTIR analyzed. The amount of crystalline structures drives the digestion rate, which is lower with HMT, where higher granular reinforcement occus. [ABSTRACT FROM AUTHOR]