Hard-to-cook phenomenon in chickpeas (Cicer arietinum L): effect of accelerated storage on quality

Cookability of 24 pea accessions-determining factors and potential predictors of cooking quality

BACKGROUND

Cooking time and cooking evenness are two critical quantities when determining the cooking quality (termed cookability) of pulses. Deciphering which factors contribute to pulse cookability is important for breeding new cultivars, and the identification of potential cookability predictors can facilitate breeding efforts. Seeds from 24 morphologically diverse pea accessions were tested to identify contributing factors and potential predictors of the observed cookability using a Mattson cooker. Size- and weight-based measures were recorded, and seed-coat hardness was obtained with a penetrometer. Content of protein, starch (amylose and amylopectin), and phytate was also determined.

RESULTS

Distinct differences were found between wrinkled and non-wrinkled seeds in terms of water-absorption capacity, seed-coat hardness, and plunger-perforation speed. Potential predictive indicators of cooking time and cooking evenness were seed-coat hardness (r = 0.49 and r = 0.38), relative area gained (r = -0.59 and r = -0.8), and percentage of swelled seeds after soaking (r = -0.49 and r = -0.58), but only for non-wrinkled seeds. Surprisingly, the coefficients of variation for the profile area of both dry and swelled seeds appeared to be potential cookability predictors of all pea types (correlation coefficients around r = 0.5 and supported by principal component analysis). However, no strong correlation was observed between cookability and protein, starch, or phytate levels.

CONCLUSION

Using three types of instruments together with chemical components enabled the identification of novel cookability predictors for both cooking time and cooking evenness in pea. This study unveils the diverse quantitative aspects influencing cookability in pea. Considering both cooking time and cooking evenness, as well as seed-coat hardness, underscores the multifaceted nature of pulse cookability and offers important insights for future breeding strategies to enhance pea cultivars. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Insight into pectin-cation-phytate theory of hardening in common bean varieties with different sensitivities to hard-to-cook

In this study, a detailed quantitative analysis of the mechanisms linked with pectin-cation-phytate hypothesis of hard-to-cook development (HTC) was evaluated to assess the plausibility of this hypothesis. Several common bean varieties with varying sensitivities to HTC were characterized for pectin, cell wall bound calcium and inositol hexaphosphate (InsP₆) content before and after ageing. Ageing resulted in a significant decrease in InsP₆ content (resulting in calcium release) in all varieties. Despite not significantly changing during ageing, the cell wall bound calcium content significantly increased in most aged bean varieties upon short cooking indicating enhanced internal cation migration during the early phase of cooking in contrast to during ageing and soaking. Among the parameters evaluated in this study, the relative changes in InsP₆ content significantly correlated with the change in cooking times as well as changes in cell wall bound calcium content. Results obtained in this study suggest that in some bean varieties, pectin-cation-phytate hypothesis is the predominant mechanism by which hardening occurs during storage while in other varieties, the role of other factors such as phenolic crosslinking as suggested in literature cannot be ruled out.

How postharvest variables in the pulse value chain affect nutrient digestibility and bioaccessibility

Pulses are increasingly being put forward as part of healthy diets because they are rich in protein, (slowly digestible) starch, dietary fiber, minerals, and vitamins. In pulses, nutrients are bioencapsulated by a cell wall, which mostly survives cooking followed by mechanical disintegration (e.g., mastication). In this review, we describe how different steps in the postharvest pulse value chain affect starch and protein digestion and the mineral bioaccessibility of pulses by influencing both their nutritional composition and structural integrity. Processing conditions that influence structural characteristics, and thus potentially the starch and protein digestive properties of (fresh and hard-to-cook [HTC]) pulses, have been reported in literature and are summarized in this review. The effect of thermal treatment on the pulse microstructure seems highly dependent on pulse type-specific cell wall properties and postharvest storage, which requires further investigation. In contrast to starch and protein digestion, the bioaccessibility of minerals is not dependent on the integrity of the pulse (cellular) tissue, but is affected by the presence of mineral antinutrients (chelators). Although pulses have a high overall mineral content, the presence of mineral antinutrients makes them rather poorly accessible for absorption. The negative effect of HTC on mineral bioaccessibility cannot be counteracted by thermal processing. This review also summarizes lessons learned on the use of pulses for the preparation of foods, from the traditional use of raw-milled pulse flours, to purified pulse ingredients (e.g., protein), to more innovative pulse ingredients in which cellular arrangement and bioencapsulation of macronutrients are (partially) preserved.

Understanding the Relations Among the Storage, Soaking, and Cooking Behavior of Pulses: A Scientific Basis for Innovations in Sustainable Foods for the Future

The world faces challenges that require sustainable solutions: food and nutrition insecurity; replacement of animal-based protein sources; and increasing demand for convenient, nutritious, and health-beneficial foods; as well as functional ingredients. The irrefutable potential of pulses as future sustainable food systems is undermined by the hardening phenomenon that develops upon their storage under adverse conditions of temperature and relative humidity. Occurrence of this phenomenon indicates storage instability. In this review, the application of a material science approach, in particular the glass transition temperature concept, is presented to explain phenomena of storage instability such as the occurrence of hardening and loss of viability under adverse storage conditions. In addition to storage (in)stability, application of this concept during processing of pulses is discussed. The state-of-the-art on how hardening occurs, that is, mechanistic insights, is provided, including a critical evaluation of some of the existing postulations using recent research findings. Moreover, the influence of hardening on the properties and processing of pulses is included. Prevention of hardening and curative actions for pulses affected by the hardening phenomenon are described in addition to the current trends on uses of pulses and pulse-derived products. Based on the knowledge progress presented in this review, suggestions for the future include: first, the need for innovation toward implementation of recommended solutions for the prevention of hardening; second, the optimization of the identified most effective and efficient curative action against hardening; and third, areas to focus on for elucidation of mechanisms of hardening, although existing analytical methods require advancement.

Physicochemical Properties and Effect of Processing Methods on Mineral Composition and Antinutritional Factors of Improved Chickpea (Cicer arietinum L.) Varieties Grown in Ethiopia

Chickpea (Cicer arietinum L.) is an important pulse crop grown and consumed all over the world because it is a good source of carbohydrates and protein. However, presence of antinutritional components restricts its use by interfering with digestion of macronutrients during consumption. Therefore, the objective of this study was to evaluate physicochemical properties and effect of processing methods on antinutritional factors and mineral composition of improved chickpea varieties (Natoli of Desi and Arerti of Kabuli) grown in Ethiopia. The experiment was factorial with complete randomized design. The result indicated that physicochemical properties such as seed mass, seed density, hydration capacity, swelling capacity, unhydrated seeds, and cooking time of Arerti and Natoli chickpeas had 260.69 and 280.65 g/1000 seeds, 3.48 and 3.61g/ml, 1.07 and 1.03 g/g, 2.12 and 1.94ml/g, 1.64 and 14.75%, and 21.00 and 246.33 min, respectively. After processing, Zn, Fe, and Ca contents of improved chickpea varieties had 4.48 to 5.85mg/kg, 8.52 to 10.17mg/kg, and 536.56 to 1035mg/kg, respectively. The antinutritional factors, tannin and phytic acid, in the raw chickpeas were reduced to 25 to 82.25% and 5.89 to 57.35%, respectively. The results of the current study showed that Arerti of Kabuli variety showed low antinutritional factors and better physicochemical properties, specifically low cooking time, than Natoli of Desi variety. All processing methods were effective in reduction of antinutritional factors; however, boiling was found to be the best for reduction of antinutritional factors.

Quality of a Chickpea-Based High Protein Snack

A chickpea-based high protein, ready-to-eat snack was prepared using six chickpea types. The chickpea seeds and their corresponding snack products were analyzed for proximate composition, antinutrients, and select quality parameters. Chickpea types had: lipid (4.25% to 6.98%), moisture (6.63% to 9.15%), protein (23.33% to 30.95%), and carbohydrate (54.60% to 60.40%) contents exhibiting significant (P ≤ 0.05) differences. Ash content (1.94% to 2.41%) did not register significant differences. Chickpea types did not show variability in either polypeptide profile or in vitro protein digestibility. In the tested seeds, hemagglutinins and α-amylase inhibitors were not detected, while trypsin (12.73 to 19.58 units/mg sample) and chymotrypsin inhibitors (62.91 to 84.91 units/mg sample) activity varied significantly (P ≤ 0.05). The chickpea-based snack product had intermediate-moisture (23.31% to 27.81%), was low in lipids (5.09% to 5.84%), free of antinutrients, and was a good source of proteins (12.45% to 14.10%), carbohydrates (51.86% to54.96%), and minerals (1.53% to 2.43%). The L^* , a^* , and b^* values of the products ranged from 75.97 to 79.38, 3.46 to 4.75, and 27.65 to 34.65, respectively. The hardness, springiness, and fracturability of the product were 700.89 to 955.23 g, 43.38% to 47.14%, and 5.26 to 5.90 mm, respectively. PRACTICAL APPLICATION: Development of new bean-based products, such as a chickpea-based snack with an overall good nutrition and taste, may play an important role in increasing the consumption of underutilized dry beans in the United States, shown to promote better health and wellness.

Texture and interlinked post-process microstructures determine the in vitro starch digestibility of Bambara groundnuts with distinct hard-to-cook levels

Particular storage conditions are described to promote the development of the hard-to-cook (HTC) phenomenon for most legumes. However, it is not clearly established whether the HTC phenomenon influences starch digestion kinetics. Therefore, this study explored how the HTC phenomenon influences in vitro starch digestion of Bambara groundnuts, taking into account three distinct HTC levels. Stored Bambara groundnuts required prolonged cooking times. Increasing storage time led to a decrease in the rate constant of texture degradation, signifying the development of the HTC phenomenon. For cooking times of 60 min and 120 min, high HTC level samples exhibited higher rate constants and extents of starch digestion compared to the fresh sample. The higher rate of digestion was attributed to the high hardness that resulted in greater cell rupture and faster access of amylase to starch. Adapting cooking times of Bambara groundnuts with distinct HTC levels to obtain equivalent hardness values and microstructures resulted in comparable starch digestion kinetics. Spectrophotometric analysis overestimated the amount of digested starch, in contrast to the more accurate HPLC analysis, which further provided more insight by quantifying multiple digestion products. This work demonstrates that it is the hardness and interlinked pattern of cell failure (microstructure) that determines starch digestion of Bambara groundnuts with distinct HTC levels.

Comparison of color, anti-nutritional factors, minerals, phenolic profile and protein digestibility between hard-to-cook and easy-to-cook grains from different kidney bean (Phaseolus vulgaris) accessions

The present study was aimed to evaluate the differences among anti-nutritional factors in relation to mineral absorption and protein digestibility of Easy-to-cook (ETC) and Hard-to-cook (HTC) grains from different kidney bean (KB) accessions.HTC grains showed lower a* (redness to yellowness) and b* (greenness to blueness) values and L* value than ETC grains. HTC grains had significantly higher Ca and Zn and lower Cu, Mn and Fe than ETC grains. ETC and HTC grains showed significant variation in mineral, total phenolic content (TPC), tannin and phytic acid content. TPC and tannin content were significantly higher for HTC grains, on the contrary phytic acid content was lower than counterpart ETC grains. Protein and in vitro protein digestibility (IVPD) also varied significantly between HTC and ETC grains and was found to be lower for HTC grains. Majority of phenolic compounds (PCs) were present in bound state in both ETC and HTC grains. Moreover, HTC grains showed higher amount of chlorogenic acid and catechin content than ETC grains in bound form. ETC and HTC grains from dark color accessions showed higher catechin content.

Triple-Layer Plastic Bags Protect Dry Common Beans (Phaseolus vulgaris) Against Damage by Acanthoscelides obtectus (Coleoptera: Chrysomelidae) During Storage

Fumigated dry common beans (Phaseolus vulgaris L.) that were artificially infested with Acanthoscelides obtectus Say, and others that were not artificially infested, were stored in hermetic triple-layer PICS (Lela Agro, Kano, Nigeria) or woven polypropylene (PP) bags for 6 mo at ambient laboratory temperature conditions of 22.6 ± 1.9°C and 60.1 ± 4.3% relative humidity. In an additional trial, beans contained in PP bags were treated with Actellic Super dust before introducing A. obtectus. Moisture content, number of live adult A. obtectus, seed damage, weight loss, and seed germination were determined at monthly intervals. At 6 mo, beans stored in PICS bags retained higher moisture than those stored in PP bags, but in all treatments the moisture level remained below that recommended for safe storage of beans. In the PICS bags, proliferation of A. obtectus did not proceed and at 6 mo, beans stored in these bags did not have insect-inflicted seed damage or weight loss. In contrast, seed damage and weight loss in PP bags exceeded economic threshold after 1 mo in the absence of Actellic Super dust (Syngenta Crop protection AG, Basle, Switzerland), and after 2 mo in the presence of it. Germination of beans stored in PP bags decreased greatly whereas the beans stored in PICS bags did not show reduced germination. Chemical free storage of common beans in PICS bags protects them against damage by A. obtectus.

Angiotensin-converting enzyme inhibitory and antioxidative activities and functional characterization of protein hydrolysates of hard-to-cook chickpeas

BACKGROUND

The potential use of hard-to-cook (hardened) chickpeas to obtain value-added functional food ingredients was evaluated. For that purpose, some nutraceutical and functional attributes of several chickpea protein hydrolysates (CPHs) prepared from both fresh and hard-to-cook grains were evaluated.

RESULTS

All the CPHs prepared from both fresh and hard-to-cook grains, with the enzymes alcalase, pancreatin and papain, showed high angiotensin converting enzyme inhibitory (ACE-I) activity with IC₅₀ values ranging from 0.101 to 37.33 µg mL⁻¹; similarly, high levels of antioxidant activity (around 18.17-95.61 µmol Trolox equivalent antioxidant capacity µg⁻¹ CPH) were obtained through both the 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) methods. Regarding functional characterization of the CPHs, oil absorption values ranged from 1.91 to 2.20 mL oil g⁻¹ CPH, with water solubility almost 100% from pH 7 to 10.

CONCLUSION

The high antioxidant and ACE-I activities as well as the good functional properties of the CPH prepared from both fresh and hard-to-cook grains, suggest its use in food formulations with value added in human health.

Micronisation and hot air roasting of cowpeas as pretreatments to control the development of hard-to-cook phenomenon

BACKGROUND

Cowpeas stored under conditions of high temperature and high relative humidity (HTHH) develop the hard-to-cook (HTC) defect. Cowpeas with HTC defect require long cooking times, limiting their utilisation. Heat pretreatments are aimed at inactivating the enzymes responsible for HTC defect development. In this study, two heat pretreatments, micronisation and hot air roasting, were evaluated to assess their effectiveness in controlling the HTC defect development in cowpeas after storage under HTHH conditions.

RESULTS

Micronisation and hot air roasting as pretreatments reduced the cooking time of cowpeas after storage under HTHH conditions compared with the control. The differences in the effectiveness of HTC defect control between micronisation and roasting were dependent on the degree of phytase inactivation on day 0. Phytase activity was reduced by 45 and 70% by roasting and micronisation pretreatments respectively. Reduced phytase activity was associated with higher phytate and soluble pectin contents in micronised cowpeas than in roasted cowpeas after HTHH storage. This observation is in agreement with the phytase-phytate-pectin theory.

CONCLUSION

Micronisation was more effective than hot air roasting in controlling the development of HTC defect. This was due to a higher degree of phytase inactivation in micronisation when compared with roasting.

Infant food from quality protein maize and chickpea: optimization for preparing and nutritional properties

The present study had two objectives: to determine the best combination of nixtamalized maize flour (NMF) from quality protein maize and extruded chickpea flour (ECF) for producing an infant food, and to evaluate the nutritional properties of the optimized NMF/ECF mixture and the infant food. Response surface methodology (RSM) was applied to determine the best combination of NMF/ECF; the experimental design (Lattice simplex) generated 11 assays. Mixtures from each assay were evaluated for true protein and available lysine. Each one of 11 mixtures was used for preparing 11 infant foods that were sensory evaluated for acceptability. A common optimum value for the three response variables was obtained utilizing the desirability method. The best combination of NMF/ECF for producing an infant food was NMF = 26.7%/ECF = 73.3%; this optimized mixture had a global desirability of 0.87; it contained 19.72% dry matter (DM) proteins, 6.10% (DM) lipids, 71.45% (DM) carbohydrates, and 2.83% (DM) minerals; its essential amino acids profile covered the amino acids requirements for children 10-12 years old. The infant food prepared from optimized mixture had an in vitro protein digestibility of 87.9%, and a calculated protein efficiency ratio of 1.86. Infant food could be used to support the growth of infants in developing countries.

Physico-chemical characteristics, water absorption, soaking and cooking properties of some Sicilian populations of chickpea (Cicer arietinum L.)

The physical and physico-chemical properties of several Kabuli chickpeas originating from Sicily (South Italy) were determined. Twelve genotypes in all, including two controls (ILC484, of the ICARDA genebank, and 'Calia', a traditional Italian cultivar), were analysed. A large variability among genotypes was ascertained for swelling capacity (coefficient of variation [CV] = 27.9%), swelling index (CV = 30.5%) and calcium content (CV = 39.3%). The lowest variability was observed for seed coat (CV = 8.6%) and seed weight (CV = 9.6%). Genotype statistically affected all traits, whose mean values were: seed weight, 0.340 +/- 0.03 g; seed coat, 4.47 +/- 0.38%; seed volume, 0.292 +/- 0.04 ml; seed density, 1.18 +/- 0.15 g/ml; hydration capacity, 0.361 +/- 0.09 g/seed; hydration index, 1.05 +/- 0.21; swelling capacity, 0.346 +/- 0.10 ml/seed; swelling index, 1.21 +/- 0.37; cooking texture, 2.61 +/- 0.38 kg/cm(2); and calcium, 109.6 +/- 43.11 mg/100 g dry weight. Correlation coefficients among characteristics were also estimated. The genotype '44M33' was found to be interesting having good seed weight and low seed coat incidence and calcium content, all important attributes affecting cooking quality.