Browsing by Subject "Faba bean"

Previous studies have demonstrated that legume proteins have high potential to lose their native functional properties during conventional wet fractionation, since heating and drying in the processes can lead to protein aggregation and solubility reduction. However, the effect of this process on faba bean protein has not been investigated thoroughly before, according to the literature review. Therefore, the aim of this study was to investigate the influence of wet fractionation process with and without spray drying on faba bean protein gelling properties. The hypothesis was that protein isolate produced with isoelectric precipitation without spray drying would have better solubility and gelling properties than spray dried isolate. Faba bean protein concentrate (FBPC) was used to prepare faba bean protein isolate with alkaline extraction followed by isoelectric precipitation, which was then dispersed into water and neutralized (faba bean protein slurry, FBPS). Some of FBPS was spray-dried (pilot faba bean protein isolate, FBPI-P). Commercial faba bean protein isolate (FBPI-C) was used as a reference sample. Their (FBPC, FBPS, FBPI-P, FBPI-C) functionality was studied by measuring thermal denaturation (DSC), protein solubility, particle size and light microscope pictures. In addition, glucono delta lactone (GDL) induced oil-in-water emulsion gels were prepared from FBPS, FBPI-P and FBPI-C. Water holding capacity (WHC), rheological and texture properties were measured from the gel samples. Surprisingly the obtained results of faba bean in this study were different from previous research on other legume proteins. It was found that spray-dried FBPI-P showed better gelling properties than wet based FBPS. This might be due to differences in thermal denaturation. Based on DSC curves, FBPI-C was found to be fully denatured and in a poor solubility. Interestingly, GDL-induced gels had strongest gel properties, which might be highly related to industrial manufacturing process of FBPI-C. When considering the theoretical environmental impact of these processes, FBPS could show potential of being more environmentally friendly process, as it could be more energy efficient than processes which require drying and heating. It was demonstrated that FBPS showed almost as good functional properties as the pilot spray-dried isolate. Hence, FBPS could work as functional and more environmentally friendly option for food industry. Future study could be conducted in near future about FBPS safety, technological applications, process optimization and environmental impact.

Faba bean (Vicia faba L.) is a widely-cultivated legume with high nutritional value, especially rich in protein. However, the presence of antinutitional factors (e.g. phytic acid, condensed tannins, vicine and convicine and others) are hindering its utilization. Lactic acid fermentation is widely applied in food production and it is closely related with the promotion of nutritional, technological and health properties of the fermented food. The aim of this master’s thesis was to explore several functional characteristics of 28 lactic acid bacteria previously isolated from Italian and Finnish faba bean sourdoughs. In this study, phytase activity, β-glucosidase activity and the effect on degradation of condensed tannins, which are potentially directed towards reduction of anti-nutritional factors, were investigated. Three peptidase activities and dextran production capacity of the isolates were also evaluated. Besides, six antibiotics were used to study antibiotic susceptibility among the strains. Leuconostoc mesenteroides I01 and Pediococcus pentosaceus I214 expressed the highest phytase activity while P. pentosaceus I02, F01, F213 had the highest β-glucosidase activity. P. pentosaceus F15 was the most effective to decrease condensed tannins. Among analyzed peptidases, PepL showed the highest activity, especially in Pediococcus strains. High dextran production capacity was observed among isolates of Weissella spp. The strains showing functional traits could be used as starter to improve the nutritional and technological properties of faba bean. Further investigation is still ongoing to evaluate other properties of these lactic acid bacteria as functional starter cultures for faba bean and legume fermentation.

Lipoxygenase enzymes, which contribute significantly to storage protein in legume seeds have been reported to cause the emission of volatile compounds associated with the generation of off-flavours. This is an are important factor limiting the acceptance of faba bean (Vicia faba) I foods. This study aimed at using bioinformatic tools to identify seed-borne lipoxygenase (LOX) genes and to design a biological tool using molecular techniques to find changes in sequence in faba bean lines. LOX gene mining by Exonerate sequence comparison on the whole genome sequence of faba bean was used to identify six LOX genes containing Polycystin-1, Lipoxygenase, Alpha-Toxin (PLAT) and/or LH2 LOX domains. Their sequence properties, evolutionary relationships, important conserved LOX motifs and subcellular location were analysed. The LOX gene proteins identified contained 272 – 853 amino acids (aa). The molecular weight ranged from 23.67 kDa in Gene 6 to 96.45 kDA in Gene 1. All the proteins had isoelectric points in the acidic range except Genes 6 and 7 which were alkaline. Only one gene had both LOX conserved domains with aa sequence length similar with that found in soybean and pea LOX genes and isoelectric properties with soybean LOX3. Phylogenetic analysis indicated that the genes were clustered into 9S LOX and 13S LOX types alongside other seed LOX genes in some legumes. Five motifs were found, and sequence analysis showed that three genes (Gene 1, 2 and 3) contained the 38-aa residue motif that includes five histidine residues [His-(X)4-His-(X)4-His-(X)17-His-(X)8-His]. The subcellular localization of the lipoxygenase proteins was predicted to be primarily the cytoplasm and chloroplast. Primers covering ~1.2 kb were designed, based on the conserved region of Genes 1, 2 and 3 nucleotide sequences. Gel electrophoresis showed the PCR amplification of the seed LOX gene at the expected region for twelve faba bean lines. Phylogenetic analysis showed evolutionary divergence among faba bean lines for sequenced and amplified region of their respective seed LOX alleles.

α-Galactosides (raffinose, stachyose, verbascose) are antinutritional factors found in pea and faba bean, that cause digestive issues for some people. Reducing the amount of α-galactosides could increase the consumption legumes. The objectives of the research were to decrease the amount of α-galactosides in pea protein concentrate (PPC) and faba bean protein concentrate (FBPC) and produce a low-FODMAP yoghurt analogue. α-Galactosides were reduced using two α-galactosidase enzymes, α-galactosidase A (two doses) and α-galactosidase B (one dose). A low-FODMAP yoghurt analogue was produced from PPC with α-galactosidase A added, and possible changes in viscosity measured. The change in the amount of α-galactosides was determined with the Megazyme raffinose/sucrose/glucose kit. α-Galactosides were completely eliminated with the bigger dose of α-galactosidase A. Differences were observed in the α-galactosidase treatment samples treated with the different enzymes and doses. FBPC has more verbascose than PPC which takes the longest time to hydrolyse (compared to stachyose and raffinose) due to the exoglycosidase action of the enzyme. It could be the reason to differences in reduction of α-galactosides in FBPC and PPC. The bigger dose of α-galactosidase A reduced α-galactosides similarly in FBPC and PPC after six hours but differences in the reduction of α-galactosides were observed in the other two doses in FBPC and PPC. A low-FODMAP yoghurt analogue with no changes in structure in terms of viscosity between the α-galactosidase treated and control samples was seen.

Faba bean flour is a sustainable and relatively inexpensive way to make protein rich food in comparison with meat products, because it has high proteins content (rich in lysine (30%)) and considerable amounts of vitamins, minerals and dietary fibre. Even rough faba bean is widely cultivated and consumed, few data is available concerning the suitability to be fermented. The objective of this master’s thesis was to study the potential of sourdough fermentation of faba bean with selected lactic acid bacteria for in situ production of dextrans as texture forming components for various food applications. In this study, the growth and dextran formation by Leuconostoc and Weissella in faba bean sourdoughs were investigated. Eight lactic acid bacteria belonging to genera Leuconostoc and Weissella characterized for slime formation were used as starters for in situ formation of exopolysaccharides in faba bean flour. The growth of lactic acid bacteria, pH and acidity, and viscosity of different sourdoughs were analyzed. An enzyme assisted method and acid hydrolysis were used to analyze dextran content with further quantification by HPAEC-PAD. The amount of dextran formed by Leuc. pseudomesenteroides DSM 20193, Leuc. mesenteroides subsp mesenteroides LMG 7939, Leuc. Citreum DSM 5577, W. cibaria LMG 17699, and W. cibaria Sj1b varied from 1.86 to 4.22 g kg-1 (wet weight), which allows the possibilities to use dextran as alternatives for hydrocolloids in food applications. The synthesized dextran increased significantly viscosity of sourdoughs. After fermentation, the amount of raffinose family oligosaccharides (RFO) were decreased. The results of the sourdough fermented faba bean flours showed that Leuc. pseudomesenteroides DSM 20193 and Leuc. Mesenteroides subsp mesenteroides LMG 7939 were the most potential strains to produce dextrans and increase viscosity properties.