Bread is a major staple food consumed daily in all parts of the world. A significant part of the human population cannot tolerate gluten, a storage protein found in wheat, rye and barley, and therefore, products made from alternative cereals are required. During this study, the bread-making potential of seven gluten-free flours, wheat and wholemeal wheat flour was compared. Fermentation potential of the different flours was determined, showing that dough development height of gluten-free and wholemeal wheat samples was lower than for wheat and oat flour. Apart from standard bread quality parameters such as loaf-specific volume and physical crumb texture, also water activity and shelf life have been determined. The shelf life of gluten-free breads was reduced compared to wheat bread. Aroma profiles were evaluated by a trained panel. Wheat, oat and wholemeal wheat breads were liked moderately, while the remaining samples had lower liking scores. Crumb grain characteristic s were investigated using image analysis, and microstructure was observed by scanning electron microscopy. Overall, only breads produced from oat flour were of similar quality to wheat bread, and the utilization of buckwheat, rice, maize, quinoa, sorghum and teff flours resulted in breads of inferior quality

Dry fractionated faba bean protein-rich flour (FPR) produced by milling/air classification, and faba bean protein isolate (FPI) produced by acid extraction/isoelectric precipitation were compared in terms of composition, techno-functional properties, nutritional properties and environmental impacts. FPR had a lower protein content (64.1%, dry matter (DM)) compared to FPI (90.1%, DM), due to the inherent limitations of air classification. Of the two ingredients, FPR demonstrated superior functionality, including higher protein solubility (85%), compared to FPI (32%) at pH 7. Foaming capacity was higher for FPR, although foam stability was similar for both ingredients. FPR had greater gelling ability compared to FPI. The higher carbohydrate content of FPR may have contributed to this difference. An amino acid (AA) analysis revealed that both ingredients were low in sulfur-containing AAs, with FPR having a slightly higher level than FPI. The potential nutritional benefits of the aqueous process compared to the dry process used in this study were apparent in the higher in vitro protein digestibility (IVPD) and lower trypsin inhibitor activity (TIA) in FPI compared to FPR. Additionally, vicine/convicine were detected in FPR, but not in FPI. Furthermore, much lower levels of fermentable oligo-, di- and monosaccharides, and polyols (FODMAPs) were found in FPI compared to FPR. The life cycle assessment (LCA) revealed a lower environmental impact for FPR, partly due to the extra water and energy required for aqueous processing. However, in a comparison with cow’s milk protein, both FPR and FPI were shown to have considerably lower environmental impacts.

The formation of a green or beany off-flavor during storage of legume protein extracts limits their application in foods. Pea protein extracts were submitted to lactic acid fermentations to improve the flavor by either reducing off-flavor formation or by masking undesirable green notes. The aroma profiles of untreated pea protein extract (PPE) and fermented pea protein extract (PPEF) were compared to each other and to a commercial whey protein as a benchmark. Kinetic measurements of n-hexanal and n-hexanol formation were used as an indicator for progressing lipid oxidation and storage stability. The nonfermented and fermented pea protein extracts showed a shelf-life comparable to the commercial whey protein reference. Volatiles were identified and quantified using dynamic headspace sampling with subsequent coupled TDS-GC-MS and TDS-GC-olfactometry flavor dilution analysis. A total of 18 odorants with dilution factors equal to or higher than 100 were determined in PPE an d 17 in PPEF. Altogether, 23 highly odor-active compounds were identified according to their mass spectra, odor impressions, linear retention indices, and standard substances in PPE and PPEF, among them n-hexanal, 1-pyrroline, dimethyl trisulfide, 1-octen-3-one, 2,5-dimethyl pyrazine, 3-octen-2-one, -damascenone, and guaiacol. The fermentation considerably amended the aroma profile of pea protein preparations resulting in a reduction or a masking of undesirable flavors

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This paper describes a pilot process for obtaining protein isolates from white lupin seed with improved water solubility and technofunctional properties as well as reduced thermal damage. After a careful optimization of the process parameters, two valuable food ingredients were prepared: lupin protein isolate type E, with a useful emulsifying capacity, and lupin protein isolate type F, with a high capability of foam formation and stabilization. The spray-drying process was particularly critical for inducing some thermal damage, but a careful selection of the conditions permitted ingredients having only marginally impaired lysine bioavailability to be obtained. The reproducibility of the protein extraction process was tested on two different lupin varieties.