Study on Protein Structures of Eight Mung Bean Varieties and Freeze-Thaw Stability of Protein-Stabilized Emulsions

Abstract

In order to evaluate the freeze-thaw stability of mung bean protein isolate (MPI)-stabilized emulsions and its relationship with protein structure, proteins of eight mung bean varieties were compared. The results revealed that MPIs prepared from all eight varieties were mainly composed of five subunit bands, with albumin and globulin content ranges of 188.4–310.3 and 301.1–492.7 mg/g total protein, respectively. Protein structural analysis revealed that random coil structure (32.34%–33.51%) accounted for greater than 30% of MPI secondary structure. Meanwhile, analysis of protein properties revealed emulsifying activity index (EAI), emulsifying stability index (ESI) and flexibility value ranges of 6.735–8.598 m2/g, 20.13–34.25% and 0.125–0.182, respectively. Measurements of freeze-thaw stability of MPI emulsions demonstrated that exposures of emulsions to multiple freeze-thaw cycles resulted in significantly different emulsion creaming index, oiling-off, particle size and zeta potential values for the various emulsions. Moreover, the stabilities of all eight protein emulsions decreased with each freeze-thaw cycle, as demonstrated using optical micrographs. The correlation analysis method was used to study the correlation between the original structures, emulsifying properties of proteins and the freeze-thaw stability of MPI emulsions. Correlation analysis results revealed significant relationships between albumin content, subunit bands with a molecular weight of 26.9 kDa and emulsifying properties were significantly related to the freeze-thaw stability of MPI emulsion. Thus, by determining these indicator values, we can predict the freeze-thaw stability of MPI-stabilized emulsions.

Dry fractionation of Australian mungbean for sustainable production of value‐added protein concentrate ingredients

“…Stretching vibration peaks for MB‐PC and MB‐PI were observed at wavenumbers around 1635 and 1645 cm −1 , respectively, indicating that the ordered structure of MB‐PC and MB‐PI was predominantly based on the β‐sheet structure. Similar results were reported by Sun et al (2022) in mungbean protein isolates, where stretching vibration peaks were found within the spectral region around 1641 cm −1 , showing that the β‐sheet was also the dominant structure.…”

Optimization of extraction parameters of protein isolate from milk thistle seed: Physicochemical and functional characteristics

“…A similar trend was noticed in hemp seed protein, whose PS increased from 0% to around 80% following isoelectric point pH 5 up to pH 10 (Hadnađev et al, 2018) was 7.27 m 2 /g (Rao et al, 2002). In addition, eight mung bean protein isolates showed EAI of 6.735-8.598 m 2 /g (Sun et al, 2022).…”

“…The EAI value of acid‐precipitated soy protein concentrate (86.7% protein) was 7.27 m 2 /g (Rao et al., 2002 ). In addition, eight mung bean protein isolates showed EAI of 6.735–8.598 m 2 /g (Sun et al., 2022 ). ESI of hemp seed proteins was found to be around 50 min (Li et al., 2022 ).…”

“…A similar trend with other studies regarding protein isolates was noticed in this study. The zeta potentials of eight varieties of mung bean protein isolate (MPI) were between −35 and −30 at pH 7 (Sun et al., 2022 ). Zeta potential of flaxseed protein isolate (FPI) was displayed in the pH range of 2.0–8.0, and the highest negative charge was noticed at pH of 8.0 due to enhanced anionic group exposure on the protein surface.…”

Utilization of Vermicompost and Npk Fertilizers on the Growth, Yield, Nutrient and Protein Content of Mung Bean (Vigna Radiata L.)

“…Nutritionally, mung bean is the best and most popular crop of all pulses in Bangladesh. It is reported (Sun et al 2022) that mung bean provides a high amount of protein (24.5%), lysine (460 mg/g N) and tryptophan (60 mg/g N). It is digestible and tasty.…”