Angiotensin I-converting enzyme inhibitory activity of chickpea and pea protein hydrolysates

ACE inhibitory activity was studied for different hydrolysates obtained from protein concentrates of chickpea (kabuli and desi) and yellow pea (Golden) using in vitro gastrointestinal simulation, alcalase/flavourzyme, and papain. Protein/peptide profiles studied by SDS–PAGE and SE-HPLC, showed a rich composition of the hydrolysates in small peptides having MWs under 4 kDa. Papain hydrolysed yellow pea proteins showed the highest ACE inhibitory activity. In addition, chickpea desi proteins hydrolysed by in vitro gastrointestinal simulation showed higher ACE inhibition (IC₅₀ of 140 ± 1 μg/ml) compared to its digests obtained by alcalase/flavourzyme (IC₅₀ of 228 ± 3 μg/ml) or papain (IC₅₀ of 180 ± 1 μg/ml) and to chickpea kabuli hydrolysed by gastrointestinal simulation (IC₅₀ of 229 ± 1 μg/ml). The results demonstrate that enzymatic hydrolysates of chickpea and pea proteins contain bioactive ACE inhibitory peptides; furthermore, the type of enzyme used for hydrolysis affects the ACE inhibitory activity.     

Subunit,amino acid composition and in vitro digestibility of protein isolates from Chinese kabuli and desi chickpea (Cicer arietinum L.) cultivars

The subunit, amino acid composition and in vitro digestibility of the two protein isolates (GCPI and ZCPI) from one kabuli and one desi chickpea cultivars, grown extensively in Xinjiang Autonomous Region of China, were investigated and compared with those of soy protein isolate (SPI). SDS–PAGE showed that GCPI and ZCPI had almost the same band components under the reduced and unreduced conditions, with only minor difference in relative quantity for some bands, but different from that of SPI. The sulphur-containing amino acids were the first limiting amino acids for all three protein isolates of GCPI (2.11 g/100 g), ZCPI (2.20 g/100 g) and SPI (1.99 g/100 g). Amino acid score of the three protein isolates could reach the FAO/WHO requirement (1990) for the essential amino acids for preschool children. The order of in vitro digestibility was GCPI (87.47%) > ZCPI (80.82%) > SPI (71.04%). Our results indicated that, compared with soybean protein isolate, Chinese kabuli and desi chickpea protein isolates had higher digestibility value, and chickpea protein, especially for kabuli protein, could be utilized as a good source of protein for human nutrition.     

Physicochemical and functional properties of protein concentrates from pulses

The physicochemical and functional properties of protein concentrates from peas, lentils, navy beans, chickpeas, and defatted chickpeas were investigated. Protein concentrates were prepared using a laboratory wet milling procedure. Chemical composition and colour of the protein concentrates were significantly different among the various pulses. Functional properties of the chickpea protein concentrates, including water hydration capacity, foaming capacity, and emulsion capacity, were improved significantly after a defatting step was added prior to the fractionation process. Navy bean protein concentrate had the largest foaming capacity, whilst chickpea protein concentrates had the smallest. Protein concentrates from lentils had the most stable foams after 120 min, whilst those from chickpeas had the least stable foams. Navy bean protein concentrate also had the highest emulsion capacity, whilst pea protein concentrates had the poorest. Protein content of the protein concentrates was positively correlated, whilst the fat content was negatively correlated with foaming capacity (r = 0.663, p < 0.001 and r = − 0.712, p < 0.001, respectively). Water hydration capacity of the protein concentrates was significantly correlated with ash content (r = 0.597, p < 0.01), fat absorption (r = 0.535, p < 0.01), foaming capacity (r = 0.775, p < 0.001) and foam stability at 120 min (r = 0.595, p < 0.01). Ash content and foaming capacity were significantly correlated with emulsion capacity (r = 0.497, p < 0.05, and r = 0.552, p < 0.01, respectively).     

A Method to Estimate the Hydration and Swelling Properties of Chickpeas (Cicer arietinum L.)

ABSTRACT:  Existing methodologies for estimating hydration properties in pulses (a potential indicator of cooking time) can be misleading and few measure both maximum hydration and the rate of hydration. Therefore, a new method, based on the Mitscherlich equation, was proposed and compared to existing methodologies. It was shown to be a superior estimator of both maximum hydration and hydration rate in desi and kabuli chickpeas. The new method was also superior for estimating maximum swelling and the rate of swelling in desi and kabuli chickpeas. Hydration and swelling data for 6 desi and 4 kabuli chickpea genotypes were compared using the new method and showed large genotypic differences. Use of the new method is recommended for estimating the hydration parameters of desi and kabuli chickpea for industry purposes and for selection of genotypes in breeding programs.     

Physico-chemical properties and nutrient composition of beach pea (Lathyrus maritimus L.)

Physico-chemical properties of Beach pea (Lathyrus maritimus L.) seeds were evaluated and their proximate composition determined. Results were also compared with those of green pea (Pisum sativum) and field pea (Lathyrus sativus). Beach pea seeds had a very low grain weight, density, hydration capacity, hydration index, swelling capacity and swelling index as compared to green pea and field pea. The contents of crude protein (29.2%), crude fibre (12.0%), reducing sugars (0.2%), total phenolics (1.2%) and ash (3.0%), and total free amino acids (0.6%) of beach pea were substantially higher than other pea varieties examined. The contents of cysteine (1.6%), methionine (1.1%), and tryptophan (0.3%) in beach pea proteins were low, but higher than those in green pea and field pea varieties from Canadian and Indian cultivars. Beach pea lipids were dominated by linoleic acid (69.1%), and were similar to green pea (45.1%) and Canadian grown field pea (57.0%). The macroelements of beach pea were dominated by potassium (476 mg/100 g), phosphorus (413 mg/100 g), magnesium (1180 mg/100 g), and calcium (144 mg/100 g). The contents of microelements, namely manganese, zinc, and iron in beach pea were 3.5, 3.0 and 9.4 mg/100 g, respectively.     

Certain physicochemical and functional properties of fibre fractions from pulses

The physicochemical and functional properties of the fibre fractions from peas (Pisum sativum), lentils (Lens culinaris), chickpeas (Cicer arietinum L.) and navy beans (Phaseolus vulgaris) were evaluated, and the relationships amongst those properties were determined. Fibre fractions from several varieties of each species were prepared using a laboratory wet milling procedure. The fibre fractions contained 663.2 to 808.5 g/kg DM of total dietary fibre, 45.4 to 171.1 g/kg DM of crude protein, 102.7 to 195.6 g/kg DM of starch and 1.9 to 10.5 g/kg DM of crude fat. Fibre fractions from pea and kabuli chickpea displayed significant higher fat absorption (FA) than those from lentil, navy bean and desi chickpea. Lentil and navy bean fibre fractions exhibited larger mean particle size than did pea and chickpea fibre fractions. Pulse fibre fractions exhibited significantly higher water hydration, swelling and water retention capacities in comparison to commercial pea fibre products. A significant reverse relationship (r = − 0.956, p < 0.001) between mean particle size and specific surface area (SpSA) of pulse fibre fractions was observed. FA of fibre fractions was positively correlated with SpSA (r = 0.820, p < 0.001).     

Carbohydrate composition of raw and extruded pulse flours

Extrusion cooking technology is commercially used in the fabrication of a variety of snack-type and ready-to-eat foods made from cereal grains. However, with the exception of soybean, pulses such as lentil, dry pea and chickpea have not been used for the development of extruded food products. In this study, total carbohydrates, mono-, di- and oligosaccharides, and soluble and insoluble dietary fiber were determined before and after extrusion cooking under specific processing conditions. Concentrations of total available carbohydrates (TAC) in lentil, chickpea and dry pea flours ranged from 625 g/kg to 657 g/kg dry matter. Dry pea showed the highest concentration of TAC, followed by chickpea and lentil. Extrusion processing did not significantly (p < 0.05) affect the TAC content of dry pea and lentil flours. However, extrusion processing decreased the concentration of the raffinose family of oligosaccharides (raffinose and stachyose) in pulse extrudates. Formulated pulse flours demonstrated a beneficial increase in dietary fiber. This research indicates that value-added, nutritious snacks with reduced levels of flatulence factors and higher contents of dietary fiber can be fabricated successfully by extrusion processing of formulations based on lentil, dry pea or chickpea, and represent good alternatives to traditional cereal-based snacks. Also, the commercialization of value-added, pulse-based snacks would increase pulse consumption.     

Influence of processing on composition and antinutritional factors of chickpea protein concentrates produced by isoelectric precipitation and ultrafiltration

The effect of chickpea processing (i.e. defatting, isoelectric precipitation vs ultrafiltration/diafiltration) on the composition, protein recovery and antinutritional factors of protein concentrates was studied for two varieties (Mylese and Xena). Defatting did not affect significantly the content of antinutritional factors in the flours. However, production of concentrates from defatted flours by isoelectric precipitation resulted in higher phosphorous and phenolic contents compared to the concentrates produced by the same process using the full fat flours as starting material, while trypsin inhibitor content was not affected. When processed by ultrafiltration/diafiltration, protein concentrates produced from defatted flour showed a slightly lower trypsin inhibitor content than the ones produced from full fat flours in most cases, while the inverse was true for the phosphorous content, and for the phenolic content; this effect was a function of chickpea variety. Overall, UF pH 9/DF pH 6 resulted in concentrates with the lowest phosphorous content, while isoelectric precipitation and UF pH 9/DF pH 9 resulted in concentrates with lower phenolic content compared to the ones produced by UF pH 9/DF pH 6; for both processes the trypsin inhibitor content of the concentrates remained high.Industrial relevanceChickpea production is one of the major agricultural sectors of significant importance to Canada. Although chickpeas are grown in Canada for export, very little is exported in the value-added or processed form. Development of new extraction technologies and value-added products such as the ones presented in this paper is of interest for Canada since it would have a significant impact on the growth of the industry domestically, thus, creating opportunities to strengthen rural development in Canada. Successful implementation of these technologies would make interested Canadian companies viable competitors in the global plant protein production industry and would put Canada in a good position to enjoy a large share of this market both locally and internationally.More specifically, we are the first research group to compare the use of isoelectric precipitation and ultrafiltration/diafiltration for the production of chickpea protein concentrates from full fat and defatted flours of Kabuli and Desi chickpea variety, and to quantify the effect of these processes on the composition and on the antinutritional factors (i.e. phytic acid, total phenolics and trypsin inhibitors) of the resulting concentrates. Overall, it was observed that isoelectric precipitation was effective to an extent in producing concentrates with low phosphorous and phenolic contents. UF pH 9/DF pH 9 was also effective to an extent in producing concentrates with low phenolic content, while UF pH 9/DF pH 6 was more efficient in producing concentrates with low phosphorous content. High-quality chickpea protein concentrates with improved nutritional properties and good functional properties could beneficially be combined with other protein sources, such as soy protein, or be used in the formulation of foods, such as meat analogues, dairy, and bakery products.     

Antioxidant activity and phenolic content of lentils (Lens culinaris), chickpeas (Cicer arietinum L.), peas (Pisum sativum L.) and soybeans (Glycine max), and their quantitative changes during processing

Total phenolic content (PC) was ～12 mg g^?1 in lentils, 2.2 mg g^?1 in chickpeas, 2.3 mg g^?1 in soybeans, 2.5 mg g^?1 in yellow peas and 1.2 mg g^?1 in green peas. Total antioxidant activity (AA) determined by ABTS (2,2′‐azinobis‐3‐ethyl‐benzthiazoline‐6‐sulfonic acid) assay was highest in lentils at around 14 μmol Trolox equivalent antioxidant capacity (TEAC) g^?1 and lowest in green peas at 1.9 μmol TEAC g^?1. Bound phytochemicals contributed to 82–85% total AA in lentils. Free phytochemicals contributed more to total AA in chickpeas, yellow peas, green peas and soybeans than bound phytochemicals. AA and PC was reduced by ～80% in lentils and <30% in yellow peas by decortication, by 16–41% in lentils, chickpeas and peas by cooking, and by 22–42% in lentils by soaking. Total AA was significantly correlated with total PC. Soybeans had the greatest ability to scavenge free radicals, inhibit lipid peroxidation and chelate metals among the legumes tested. Different legumes exhibited different AA mechanisms.     

Characterisations of kabuli and desi chickpea starches cultivated in China

The characterisation of starches from kabuli and desi type chickpea seeds was investigated by monitoring amylose content, swelling power, solubility, synaeresis, water-binding capacity and turbidity properties. Total amylose and apparent amylsoe content were 31.80% and 29.93% for kabuli and 35.24% and 31.11% for desi, respectively. The shape of starch granules varied from round to oval or elliptic. The transition temperatures (T_o, T_p and T_c) were (62.237, 67.000 and 72.007 °C) and (59.396, 68.833 and 77.833 °C) for kabuli and desi starches, respectively. The ΔH value of kabuli type was higher than that of desi type. The crystal type of chickpea starches was a typical C_A-type pattern. Breakdown and setback viscosity of kabuli starch were lower than those of desi starch, indicating high heat and shear stability. Kabuli starch showed a higher value of M_w (5.382 × 10⁷ g/mol) than desi starch (3.536 × 10⁷ g/mol). Both kabuli and desi starches belonged to low glycaemic starches from measuring starch fractions and hydrolysis index.     

Studies on Desi and Kabuli Chickpea (Cicer arietinum L.) Cultivars. The Levels of Amylase Inhibitors, Levels of Oligosaccharides and In Vitro Starch Digestibility

Amylase inhibitor activity (AIA) of chickpea extracts was investigated using pancreatic and salivary amylases. The extracts showed higher inhibitor activity towards pancreatic amylase than salivary amylase. Mean values indicated slightly higher inhibitory activity in desi than kabuli cultivars, though clear-cut differences were not observed among the cultivars. While in vitro starch digestibility of meal samples indicated no large differences among desi and kabuli types of chickpea, the mean values of digestibility of isolated starches of kabuli types was higher than those of desi types. The mean values of stachyose were higher in desi cultivars. When desi and kabuli types were considered together, stachyose and raffinose contents were not found significantly related to the concentrations of total soluble sugars while stachyose showed a significant correlation with raffinose.     

Variability of Some Physico-chemical Characters in Desi and Kabuli Chickpea Types

A collection of 50 chickpea accessions (26 kabuli and 24 desi types) was evaluated for 2 years for eight physico-chemical seed characters: 100-seed weight, hydration capacity, hydration index, coat thickness and contents of protein, oil, acid detergent fibre (ADF) and starch. Significant differences were found between desi and kabuli types for the majority of the characters. The variance component due to the genotype×year interaction was important for the hydration index, starch and protein content, showing the importance of the year effect on genotypic expression of these characters. One kabuli accession and five desi accessions with high and stable protein content were selected. There was no overlap between the variation limits of desi and kabuli for coat thickness and ADF content. There were high positive and significant correlations between seed weight and oil content for both types of chickpea.     

Comparison of sprout quality characteristics of desi and kabuli type chickpea cultivars (Cicer arietinum L.)

Effect of germination time on comparative sprout quality characteristics (proximate composition, ascorbic acid, phytic acid, invitro protein digestibility, protein solubility and sensory properties) was investigated. Sprouting significantly increased (P<0.01) the moisture, crude protein, crude fat and ascorbic acid contents and decreased nitrogen free extract (NFE). Phytic acid was reduced (P<0.01) with sprouting, but more pronouncedly so in the case of Kabuli type (73% reduction) than in desi type (32% reduction). In-vitro protein digestibility (IVDP) and protein solubility improved significantly (P<0.01) with increase in sprouting time. The overall sensory scores increased with the first (24 h) sprouting interval and then decreased. However, the acceptability scores for both chickpea types remained within the acceptable range (>5.0). Although, organoleptically the desi type chickpea sprouts were preferred over Kabuli type, the nutritional improvement due to sprouting was more pronounced in Kabuli chickpeas than their desi counterparts. Due to overall superior sprout quality, the kabuli type was more suitable for sprouting purposes.     

Effect of pulse consumption on perceived flatulence and gastrointestinal function in healthy males

Despite their demonstrated health benefits, consumption of pulses in Western societies has traditionally been low. This is, in part, due to the perception that pulses cause flatulence and gastrointestinal upset. This randomized, double-blind placebo-controlled, cross-over study assessed the impact of 28 consecutive days consumption of 100 g dry weight Kabuli chickpeas, green Laird lentils, and green peas, in comparison to a potato control, on perceived flatulence, abdominal comfort, bowel movements and overall gastrointestinal function using a questionnaire with yes/no and visual analog rankings, in 21 healthy males between the ages of 19–40. Questionnaires were completed during three phases (PRE, EARLY, LATE) of each treatment period. Chi-square (occurrence) and Wilcoxon test (severity rank) analyses revealed minor changes in occurrence and/or severity of flatulence and abdominal comfort, but no changes in overall gastrointestinal function. These results demonstrate that pulses containing oligosaccharides are well tolerated with negligible perceived changes in flatulence and overall gastrointestinal function when incorporated into the diet of healthy adult males.     

In vitro starch digestibility,expected glycemic index,and thermal and pasting properties of flours from pea,lentil and chickpea cultivars

In vitro starch digestibility, expected glycemic index (eGI), and thermal and pasting properties of flours from pea, lentil and chickpea grown in Canada under identical environmental conditions were investigated. The protein content and gelatinization transition temperatures of lentil flour were higher than those of pea and chickpea flours. Chickpea flour showed a lower amylose content (10.8–13.5%) but higher free lipid content (6.5–7.1%) and amylose–lipid complex melting enthalpy (0.7–0.8 J/g). Significant differences among cultivars within the same species were observed with respect to swelling power, gelatinization properties, pasting properties and in vitro starch digestibility, especially chickpea flour from desi (Myles) and kabuli type (FLIP 97-101C and 97-Indian2-11). Lentil flour was hydrolyzed more slowly and to a lesser extent than pea and chickpea flours. The amount of slowly digestible starch (SDS) in chickpea flour was the highest among the pulse flours, but the resistant starch (RS) content was the lowest. The eGI of lentil flour was the lowest among the pulse flours.     

Rheological properties and microstructure during rennet induced coagulation of UF concentrated skim milk

Rennet induced coagulation of ultrafiltrated (UF) skim milk (19.8%, w/w casein) at pH 5.8 was studied and compared with coagulation of unconcentrated skim milk of the same pH. At the same rennet concentration (0.010 International Milk Clotting Units g⁻¹), coagulation occurred at a slower rate in UF skim milk but started at a lower degree of κ-casein hydrolysis compared with the unconcentrated skim milk. Confocal laser scanning micrographs revealed that large aggregates developed in the unconcentrated skim milk during renneting. Following extensive microsyneresis the protein strands were shorter and thinner in gels from UF skim milk. Moreover, during storage up to 60 days (13 °C), the microstructure and the size of the protein strands of the UF gel changed only slightly. Hoelter–Foltmann plots suggested that the coagulation rate was reduced in the UF skim milk due to a high zero shear viscosity of the concentrate compared with the unconcentrated skim milk.     

Oil Absorption and Sensory Properties of a Snack Food from Chickpea Genotypes

Among the commonly consumed grain legumes the score on general acceptability of a snack food (seviya) was the highest for that from chickpea (Cicer arietinum L.) followed by lentil, pigeonpea and green gram, whereas the oil absorption by the product was highest for lentil followed by black gram, chickpea, and green gram. Different methods of dehulling did not cause any notable effects on oil absorption of chickpea seviya. The flour particle size, starch, and protein contents significantly influenced oil absorption of seviya. The oil absorption of the product differed significantly among genotypes, but clear cut differences were not found between desi and kabuli groups of chickpea genotypes.     

An economic assessment of proteins recovery from fish meal effluents by ultrafiltration

The main objective of this work was to assess the technical and economical feasibility of proteins recovery from fish meal effluents using crossflow membrane technology, namely, ultrafiltration (UF) and nanofiltration (NF).Mackerel processing effluents were pre-treated by microfiltration (MF cartridges battery of 80, 20 and 5 μm pore size) followed by UF (membrane Carbosep M2, 15 kDa MWCO) or NF (membrane Kerasep NanoN01A, 1 kDa MWCO). A suitable treatment for the fish meal effluents consisted of a MF pre-treatment followed by UF operating at 4 bar, 4 m/s, natural pH and ambient temperature. UF yielded an average permeation flux of 28 l/(m² h),¹ and 62% proteins rejection for a volume reduction factor of 2.3. Both membranes fully recovered their original permeabilities through an acidic/basic washing cycle. The economic assessment of proteins recovery from fish meal effluents by UF was accomplished for a production of 544 ton/yr of fish meal (66% protein content), yielding a net present worth of 160×10³ US$, interest rate of return of 17% and payback time of 8 years.     

Effect of cooking on the composition of beans (Phaseolus vulgaris L.) and chickpeas (Cicer arietinum L.)

The effect of cooking on levels of nutrients and anti-nutritional factors in beans and chickpeas was investigated. Significant (p < 0.05) variation existed among the beans and chickpeas with respect to their crude protein, starch, soluble dietary fiber (SDF), insoluble dietary fiber (IDF), total dietary fiber (TDF), resistant starch (RS), trypsin inhibitor activity (TIA), mineral, phytic acid, tannin, sucrose and oligosaccharide (raffinose, stachyose and verbascose) contents. Cooking beans and chickpeas in water significantly increased protein, starch, SDF, IDF, TDF, Mn and P contents (on a dry weight basis), whereas reduced ash, K, Mg, TIA, tannin, sucrose and oligosaccharide contents were observed. Colored beans (black, cranberry, dark red kidney, pinto and small red bean) contained tannins, whereas little tannin in white-colored beans (great northern and white pea bean) and chickpeas (Desi and Kabuli type) was detected.     

Characterization of low-phytate soy protein isolates produced by membrane technologies

Soy protein isolates (SPI) produced by combining electro-acidification and tangential ultrafiltration/diafiltration (UF/DF) (pH 6), were compared in terms of composition and proteins solubility with isolates produced by UF/DF (pH 9) and isoelectric precipitation (pH 4.5). Mineral and phosphorus (phytic acid) removal was enhanced for the SPI pH 6. Whey-like proteins (M.W. < 66 kDa) were also found in higher concentration for the SPI produced by membrane technologies. This difference in composition resulted in improved solubility characteristics for the SPI pH 6 by as high as 25% and 60%, when compared to the SPI pH 4.5 and SPI pH 9, respectively. Improvement in solubility was most important between pH 2 and 4.5. The quantity of H⁺ ions added to the soy protein extract (SPE) and SPI to reduce the pH from 9 to 4.5, during solubility measurement, was related to the degree of proteins aggregation, as determined by size-exclusion high-performance liquid chromatography, and at a lesser extent to their phytic acid content. For the pH range of 4.5 to 2, the degree of proteins aggregation alone determines the quantity of H⁺ ions added.Industrial relevanceSoy protein production is one of the major agricultural sectors of significant importance to North America and soy proteins represent 69% of global plant protein consumption in the world. Soy protein concentrates and isolates are produced at the industrial scale by isoelectric precipitation. This process has a high productivity, however, it also generates large volumes of effluent. The final products also have significant contents of minerals and of phytic acid, the latter of which is well known to decrease the proteins and minerals adsorption in the intestine.We were the first group to combine bipolar membrane electrodialysis (BMED) and ultrafiltration (UF) (dead-end) for the production of soy protein concentrates (Mondor, Ippersiel, Lamarche & Boye, 2004). The new approach resulted in a significant decrease of the volumes of effluent due to the use of BMED to adjust the pH of the extract prior to UF and by improving the protein washing step using diafiltration (DF). It was also shown that for the pH range 6–9, minerals and phytic acid removal was improved with a decrease in pH. In this work, we present the characteristics of a soy protein isolate with a low phytic acid/protein ratio (SPI pH 6) produced by BMED and tangential flow UF/DF applying an optimal VCR5, re-VCR 5 sequence at pH 6. The SPI pH 6 shows an improved solubility by as high as 25% and 60%, when compared to an isolate produced by isoelectric precipitation at pH 4.5 and to one produced by UF/DF at pH 9, respectively. Improvement in solubility was most important between pH 2 and 4.5 indicating that this isolate could be considered as a valuable ingredient for the formulation of fruit juice beverages or power juices, considering that the pH of these liquid food products is around 3.5.