Work

Chemical modification of grass pea (Lathyrus sativus L.) protein through phosphorylation and deamidation methods: A comparative study on structural and techno-functional properties

Year: 2025

Type: article

Abstract: • Phosphorylation and deamidation modify the structure of grass pea protein. • Deamidated protein had better techno-functionality compared to the phosphorylated. • Deamidated protein showed more than 3-fold improvement in emulsion activity index. The restricted techno-functional characteristics of grass pea protein isolate (GPPI) limit its use in food systems. This research investigates how treating GPPI with phosphorylation (2% sodium trimetaphosphate, pH 11.5) and deamidation (0.13 M acetic acid, 121°C, 10 min) affects its structure and techno-functional properties. FTIR, XRD, fluorescence spectroscopy, and FESEM analyses confirmed successful modifications, revealing changes such as altered hydrogen bonding and increased surface exposure to functional groups. The analysis of the secondary structure using circular dichroism (CD) spectroscopy showed that the amounts of α-helix and β-sheet decreased, while the amounts of β-turn and random coil increased in both phosphorylated (PGPP) and deamidated (DGPP) samples, suggesting structural unfolding. The zeta potential significantly increased in PGPP (31.65 ± 0.68 mV) and DGPP (37.34 ± 0.89 mV) compared to GPPI (25.78 ± 0.53 mV). Notable improvements were observed in the techno-functional properties of PGPP and DGPP. DGPP exhibited the highest foaming capacity (92 ± 0.86%), foaming stability (73.33 ± 1.24%), emulsifying activity index (92 ± 0.81 m 2 /g), and emulsifying stability index (74 ± 2.16 min). These findings highlight phosphorylation and deamidation as particularly effective approaches for improving GPPI techno-functional properties and expanding its potential applications in food formulations.

Source: Applied Food Research

DOI: 10.1016/j.afres.2025.101529

Authors: Fatemeh Moradi, Shiva Rezaee Tanha, Mohammad Mousavi, Hossein Kiani, Zahra Sarlak, Ehsan Parandi

Institutions: University of Tehran, Kermanshah University of Medical Sciences

Language: English

Topic: Proteins in Food Systems

Subfield: Food Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDG: Zero hunger

Open Access status: gold

Estimated APC paid: $2,050