Protein content variation in a pure line faba bean (Vicia faba) collection

A set of 840 pure line faba beans (Vicia faba L) derived by a process of cyclic single plant selection from 1979 to 1985 was used for this study. Mean content of protein was 240 g kg^?1 with a standard deviation of 18 g kg^?1 and a range of 180 to 310 g kg^?1. For eight subregional groups (Nile Valley, West Asia, Northern Europe, Southern Europe, Eastern Europe, North Africa, Ethiopia and the Indian subcontinent) and for a large and small grouping, the means and ranges of protein content were similar. There were no significant correlations between protein content and seed yield or its components. This resulted in a strong correlation (significant at P < 0.01) between seed yield and protein yield (r = 0-98), supporting the hypothesis that the optimal way to increase sustainable protein yield per hectare is to increase and stabilise seed yield.     

Trypsin-/Chymotrypsin-Inhibitoren in Samen der Puffbohne (Vicia faba)

Zusammenfassung Durch isoelektrisches Fokussieren wurden mehrere Trypsin/Chymotrypsin-Inhibitoren in Samen vonVicia faba nachgewiesen, deren isoelektrische Punkte bei pH 8,5 (Hauptpeak mit Schulter) und bei pH 9,1 (Nebenpeak mit Schulter) sowie im Bereich von pH 9,1-6,4 (Nebenpeaks mit deutlich geringeren Aktivitäten) liegen. Aus einem durch Affinitätschromatographie an trägergebundenem Trypsin erhaltenen Inhibitorgemisch wurden drei Inhibitoren durch preparative Elektrophorese in Polyacrylamidgel isoliert, die sich bei pH 9,2 und bei pH 4,0 als elektrophoretisch einheitlich erwiesen. Die Molekulargewichte liegen bei 6000 Dalton. Der Anteil an basischen Aminosäuren ist hoch, während Methionin und Isoleucin fehlen. Die Hemmwirkung ist spezifisch auf Serinproteinasen gerichtet: Neben Trypsin und Chymotrypsin werden einige mikrobielle Enzyme dieser Gruppe gehemmt. Die thermische Stabilität ist relativ groß. Die Inhibitoren ausVicia unterscheiden sich damit in einer Reihe von Eigenschaften deutlich von den Inhibitoren ausPhaseolus.

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Inhibitors for trypsin and chymotrypsin in seeds of the broad bean (Vicia faba)

Summary Several inhibitors for trypsin and chymotrypsin were detected in seeds ofVicia faba by isoelectric focussing. Their isoelectric points are at pH 8.5 (main peak with shoulder), at pH 9.1 (minor peak with shoulder) and in the range of pH 9.1-6.4 (several minor peaks with significant lower activities). From the mixture of inhibitors obtained by affinity chromatography on carrier bound trypsin, three inhibitors were isolated by preparative electrophoresis in polyacrylamide gel. On electrophoresis these inhibitors behaved uniformly at pH 9.2 and at pH 4.0. Their molecular weights are about 6000 daltons. The amount of basic amino acids is high, while methionine and isoleucine are absent. Besides of trypsin and chymotrypsin some serine proteinases of microbial origin are inhibited. The thermal stability is quite high. TheVicia inhibitors therefore differ significantly from thePhaseolus inhibitors in several properties.

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Cellulase inhibition by tannins in the testa of field beans (Vicia faba)

The testa of field bean varieties with coloured flowers contained 4–8 % tannin (measured as total phenolics) compared with less than 0.6 % in the testa of white flowered varieties. The tannin present in whole beans was almost entirely contained in the testa. The presence of high levels of tannin reduced in vitro digestibility and solubility in cellulase solutions of the testa and addition of high tannin testa decreased the solubility of cotyledon protein in acid pepsin. Water extracts of the testa from coloured-flower varieties inhibited the action of fungal cellulase and reduced the in vitro digestibility of white flowered testa and cellulose. A highly significant relationship (r= ?0.93***) was found between the tannin content and solubility in cellulase of testa for a range of 24 varieties. It is concluded that the effect of testa tannins on in vitro digestibility can be mainly attributed to their effect on cell wall digesting enzymes rather than an effect on protein solubility per se.     

Functional and electrophoretic characteristics of faba bean (Vicia faba) flour proteins as affected by germination

Faba beans (Vicia faba) were germinated at room temperature for 3 and 6 days respectively. The effect of germination on the protein fractions, protein solubility index, PAGE pattern and some functional properties i.e. emulsification capacity (EC), foaming capacity (FC), foam stability (FS), water and fat absorption capacities of the flour was studied. Germination decreased albumins, globulins and prolamins at different levels but non protein nitrogen and glutelins were increased. The protein solubility index was high at both extreme pH values with an isoelectric point (IP) at pH of 4.4-4.5. The solubility of the protein slightly increased due to germination at all the pH values. PAGE pattern revealed on obvious dissociation and utilization for both fast and slow moving protein fractions during germination. Emulsification and foaming properties vs pH profile were similar to the pattern of solubility vs pH. Both properties were high at acidic and alkaline pH's and the minimum values were at pH 4 to 5. Germination process improved EC, FC and FS of the flour in comparison with that of dry bean flour. Water absorption of faba bean flours was improved during germination but the fat absorption markedly decreased.     

Presence of two saponins in faba bean (Vicia faba L.) seeds

From faba bean (Vicia faba L.), two new saponins were isolated by Sephadex LH-20 gel filtration, ODS column chromatography and semi-preparative HPLC. Their molecular weights determined by FAB-MS were 978 and 962, respectively. Results of TLC and FTIR analyses showed that these compounds are similar to soya saponin group B. The presence of separated saponins was confirmed by TLC for seeds of four cultivars of faba bean.     

The effect of pod and seed positions on the physical and cooking properties of faba beans (Vicia faba)

The effect of pod location on plant (lower, middle and upper regions) and seed position inside the pods (nodular, middle and terminal) on certain characteristics of dry and stewed faba beans were studied. The weight, volume, relative density, seed coat (%), hydration and swelling coefficients were determined for dry seeds. Hydration and swelling coefficients, fractured beans (%), penetrometer readings and scores of colour, granulation and softness (by taste panel) were evaluated for stewed beans. The weight, volume, relative density, pH, and total and soluble solids content of the stewed liquor were also measured. Analysis of variance showed that the weight and volume of 1000 dry seeds were significantly (P<0.001) affected by pod location and seed position. Higher values were obtained for lower pods and terminal and middle seeds. Seeds from upper pods had the highest percentage of seed coat. Pod location showed a significant effect on the weight, volume, pH, soluble and insoluble solids of stewed liquor. No significant effect was found for pod location or seed positions on the characteristics of stewed beans, except the hydration coefficient which was significantly affected by pod location.     

Functional properties of the system gelatine/Vicia faba protein in dependence on the acetylation degree of the Vicia faba protein

By acetylation of Vicia faba protein it becomes in aqueous solution compatible with gelatine up to a substitution degree of about 50%. The swellability and brittleness of foils and the viscosity of aqueous solution of Vicia faba protein are increased by its acetylation and these changes can be observed in mixtures of gelatine with acetylated Vicia faba protein, too. A heat denaturation of aqueous solutions of acetylated Vicia faba protein or mixtures with gelatine leads to an increase of the viscosity; all these solutions show pseudo-plastic flow behaviour.     

The Starch of the Fababean (Vicia faba). Comparison with Wheat and Corn Starch

Fababean starch (Vicia faba) was prepared by air-classifying a fababean flour, but then required repeated water extractions to reduce the protein content to a level comparable to that found in laboratory-prepared corn- and wheat starches. Scanning electron microscopy of the fababean starch showed oval or irregularly shaped granules which were larger in average particle size than those of corn starch. Fababean starch had a higher amylose content, gelatinization temperature range and water-binding capacity, but a lower swelling power and solubility at 90 °C compared to wheat- and corn starch. Amylograph viscosities were in-between values recorded for the other 2 starches at each reference point. The observed differences in physico-chemical characteristics between the cereal starches and the legume starch were not large.     

Optimised processing of faba bean (Vicia faba L.) kernels as a brewing adjunct

Pulse (Fabaceae) grains, such as peas and beans, are derived from crops that are usually cultivated in the absence of mineral nitrogen fertiliser as these crops can obtain their nitrogen requirement naturally from the air via biological nitrogen fixation. Therefore, pulses present a significantly lower greenhouse gas (GHG) footprint than crops demanding nitrogen fertiliser, whilst also offering significant quantities of starch for the brewing and distilling industries. Mitigation of agriculture derived GHG emissions through utilisation of pulses can have a positive environmental impact. To this end, the potential of exploiting dry, dehulled faba bean (Vicia faba L.) kernel flour as an adjunct for beer production was evaluated. The impact of different temperature regimes and commercial enzymes were assessed for their effect on wort: viscosity; run‐off rate; primary amino nitrogen content and, fermentability. Faba beans demonstrated insufficient endogenous enzyme capacity for starch conversion and generated a viscous wort. However, using a stepped temperature mashing regime and exogenous enzyme additions, the faba bean wort was comparable in processability and fermentability to that of 100% malted barley wort. The faba based beer and co‐product qualities demonstrate the environmental, nutritional and commercial potential of pulses in brewing. © 2020 The Authors. Journal of the Institute of Brewing published by John Wiley & Sons Ltd on behalf of The Institute of Brewing & Distilling     

Extraction of favism‐inducing agents from whole seeds of faba bean (Vicia faba L var major)

The objective of the present study was to establish a suitable procedure by which favism‐inducing glycosides vicine and convicine could be completely removed from whole seeds of faba beans without distorting their shape or reducing their nutritive value. Detoxification procedures carried out were extraction by water or, 10 g l^?1 acid solutions (acetic, citric and phosphoric acid) using stepwise or continuous soaking procedures. Three cultivars of the beans were used in the study. In the stepwise soaking procedures, the seeds were soaked in either water or acid solution at 40 °C for different periods while in the continuous flow techniques, the solutions were constantly passed through a seed reservoir under different time–temperature–flow rate conditions. Extraction of vicine and convicine increased with increasing temperature and period of soaking and/or continuous flow of soaking solutions. Neither stepwise soaking nor autoclaving could effectively remove the favism factors from the whole seeds. The best results were obtained with continuous flow soaking in tap water, giving vicine‐ and convicine‐free seeds. The protein contents of treated seeds were only slightly affected and their physical structure remained intact. Thus, it was concluded that the latter procedure was the method of choice for detoxification of dry whole seeds. Copyright © 2005 Society of Chemical Industry     

Amino acid composition and In Vitro digestibility of some Egyptian foods made from faba bean (Vicia faba L)

Faba beans were cooked to prepare four different dishes—Medammis, Falafel, Bissara and Nabet Soup—that are widely consumed in many Middle Eastern Countries, especially in Egypt. Amino acid composition and in vitro digestibility were determined and compared to raw beans. Severe heat-processing markedly decreased some essential amino acids, especially phenylalanine, cystine, methionine and tryptophan. Protein scores were 38·1, 21·2, 39·3, 33·7 and 42·4 for raw faba beans, Medammis, Falafel, Bissara and Nabet Soup, respectively. Cooking resulted in an appreciable increase in the in vitro digestibility which amounted to 98·4% for Nabet Soup, being close to that of casein (99·6%). The in vitro digestibility values were 75·9%, 92·7%, 85·0% and 97·2% for raw beans, Medammis, Falafel and Bissara, respectively.     

Effect of nutritional status of faba bean (Vicia faba L.) on protein solubility profiles

A field experiment was carried out to study the effect of mycorrhizal inoculation. phosphorus and sulphur fertilization, under two water regimes, on protein solubility fractions of faba bean. The major protein fraction of faba bean was the globulin fraction that ranged from 69.5 to 78.1%. Phosphorus treatment significantly (P⩽0.05) increased the globulin fraction of faba bean seeds in the wet treatment but significantly (P⩽0.05) decreased it in the dry treatment. All fertiliser treatments significantly (P⩽0.05) increased the albumin fraction in the wet treatment, whereas only treatments of mycorrhiza, mycorrhiza+sulphur and mycorrhiza+phosphorus+sulphur significantly increased it in the dry treatment compared to control. With the exception of the treatment mycorrhiza+sulphur, all other fertilisation treatments showed prolamin contents of faba bean seeds, similar to that of the control in the wet treatment. The G₃-glutelin fraction of faba bean ranged from 8.9 to 14.4%. Treatments with sulphur, mycorrhiza and mycorrhiza+sulphur significantly increased the G₃-glutelin fraction, whereas phosphorus and mycorrhiza+phosphorus treatments significantly decreased it. The insoluble protein (residue) of faba bean ranged from 1.8 to 3.4%. Generally, fertiliser treatments significantly increased the insoluble protein in the wet treatment. With the exception of treatments mycorrhiza and mycorrhiza+sulphur, all other fertiliser treatments significantly increased the insoluble protein content in the dry treatment. Water regime significantly (P⩽0.05) affected the protein fractions.     

Trypsin inhibitor activity in the field bean (Vicia faba L.)

In vitro evidence is presented for the presence of a heat-labile inhibitor of trypsin in both cotyledon and testa of the field bean (Vicia faba L.). Inhibitor activity is destroyed by heating at 110°C for 40 min. The inhibitor has, in vitro, approximately one fifth of the strength of an extract of raw soyabeans.