Emulsifying properties of lentil protein preparations obtained by dry fractionation

Abstract

Dry fractionated legume protein ingredients are gaining attention as alternatives to conventional solvent extracted legume proteins, being more resource efficient and often exhibiting novel functional properties. However, lack of knowledge about the relationship between composition and functionality limit a more wide-spread use of dry-fractionated legume protein in applications. In this study, lentil fractions of different degrees of refinement were prepared using air classification having protein and starch contents of 16–59% and 4–64%, respectively. The dry fractionated lentil fractions could emulsify and stabilize 10 wt% oil-in-water emulsions, while a conventional lentil protein isolate used for comparison was not able to form stable emulsions. The latter had significantly larger mean droplet diameters (around 20 µm) due to droplet flocculation than emulsions made with the different lentil fractions ranging between 0.3 and 5.5 µm. Similar surface charges (between −22 and −31 mV) indicated that the discrepancy could be ascribed to differences in steric repulsion and mechanical strength of the interfacial layers between conventionally and dry fractionated lentil. Storage stability tests of emulsions stabilized with dry fractionated samples resulted in separation into a low and higher density phase with the individual droplets being stable against coalescence in both phases. The phase separation was attributed to gravimetrical sedimentation of larger insoluble components accumulating in the denser phase, which was impacted by the degree of refinement by air classification. The results highlight the potential of dry fractionation for the production of sustainable ingredients with unique composition and functionality.

Techno‐functional properties of dry‐fractionated plant‐based proteins and application in food product development: a review

“…Therefore, finer particle size can enhance the emulsifying properties. Funke et al 33,34 . suggested that dry‐fractionated lentil protein has a good potential in stabilizing an emulsion, corroborating the findings of Tabtabaei et al ., 10 who revealed a similar emulsifying ability comparing navy bean dry‐fractionated protein and commercial soy protein concentrate, and better foaming stability compared to the soy.…”

A comprehensive review of mung bean proteins: Extraction, characterization, biological potential, techno‐functional properties, modifications, and applications

“…Furthermore, air classification can help maintain the native functionality of proteins without the addition of chemical reagents (Schutyser et al., 2015). For instance, better solubility, foam stability, ESI, and lower viscosity reflected native techno‐functional properties compared to traditional protein isolates (Funke et al., 2022; Pelgrom et al., 2014). Although dry‐separating MBPs yield relatively lower purity than wet separation, it is expected that most foods do not require high purity (Schutyser et al., 2015).…”

Influence of the composition of sunflower meal on the efficiency of separating the protein part of the raw material from fiber by mechanical fractionation

“…При этом небелковые компоненты отделяются от белоксодержащей фракции. Для классификации измельченного сырья чаще всего используют центробежные воздушные классификаторы [9], а также рассев на ситах и электросепарацию [10]. Подбирая параметры процесса классификации, который проводят в одну или в две стадии, получают белковые продукты различного состава.…”

“…При фракционировании бобов наиболее полное отделение белка выявлено для твердых семян, а при фракционировании пшеницы -для мягких семян [5]. В работе [7] показано, что уровень сырого протеина мало влияет на эффективность фракционирования, а в исследовании [9] выявлена положительная корреляция между содержанием сырого протеина в горохе и его количеством в мелкой фракции. Содержание сырой клетчатки неоднозначно влияет на эффективность фракционирования, так как зависит от состава клеточной стенки (количество нейтрально-детергентной клетчатки) и ее толщины.…”