Atmospheric cold plasma treatment of soybean protein isolate: insights into the structural, physicochemical, and allergenic characteristics

Abstract

Currently, there has been a surge of interest in revealing the interactions between plasma and food matrices. In this study, we investigated the impacts of atmospheric cold plasma (ACP) treatment on the structural, physicochemical and allergenic characteristics of soybean protein isolate (SPI). SPI dispersions were subjected to ACP treatments at different frequencies (80 to 100 Hz) and durations (1 to 10 min) to investigate the effects of exposing conditions. Results showed that ACP induced reactive oxygen species‐mediated oxidation of soy proteins, resulting in modifications in the secondary and ternary structures of SPI. As a consequence, functional properties of SPI, such as emulsifying (56 to 168%, compared with control) and foaming properties (60 to 194%) were influenced by varying degrees. In addition, under certain circumstance (120 Hz, 5 min), the IgE‐binding level of SPI was decreased by up to 75%, when compared to the control. Moderate treatment yielded products with improved functionality and reduced allergenicity, while extensive exposure induced a loss of vendibility due to protein aggregation.Practical ApplicationIn this study, we demonstrated for the first time, that plasma species reacted with soybean proteins, resulting in spatial structural changes which are closely related with protein functionality and allergenicity. ACP interacts with macromolecules in aqueous systems and thus can be an alternative and promising nonthermal approach in modifying soybean proteins, whereas the exact role of different processing parameters needs to be well‐elaborated.

Influence of Emerging Technologies on the Utilization of Plant Proteins

“…Plasma technology (or gas discharge plasma) involves producing and using ionized gas molecules to treat a material for superficial effects, e.g., polymers functionalization and food decontamination. The gas ionization produces reactive species, e.g., ions, electrons, excited atoms, ultraviolet (UV) photons, and free radicals (81)(82)(83), that can cause different changes on the food surfaces (solids food) and food bulk. Plasma can be generated at different temperatures and classified into thermal and nonthermal (also called cold) plasma (81,84).…”

“…Cold atmospheric plasma processing (CAPP) is an emerging, sustainable, and environmentally friendly technology that has received significant attention in the food industry for the recent decade (82,83,86). CAPP can be generated by corona discharge, atmospheric-pressure plasma jet (APPJ), dielectric barrier discharge (DBD), microwave discharge (85,87), and radiofrequency (RF) (88).…”

“…CAPP has an inactivation effect on microorganisms, such as food pathogens, spores, and viruses (84,85,89). Also, it is valid for surface modification (90,91), inactivation of deteriorating enzymes (82), food packaging modification (85), and reduction of food allergenicity (83). According to processing conditions, CAPP influences food proteins' conformation and functional properties, e.g., plasma source, design, treatment power, pressure, reactive gas type, exposed time, and sample nature (84,85).…”

Characterisation of Flavour Attributes in Egg White Protein Using HS-GC-IMS Combined with E-Nose and E-Tongue: Effect of High-Voltage Cold Plasma Treatment Time

“…The nonthermal processing technique is a food processing technique that is achieved at room temperatures; it preserves food materials’ attributes whilst minimally affecting those attributes, thus preventing flavour loss, maintaining nutritional components, and extending the shelf life of the food materials [ 15 , 16 ]. High-voltage cold plasma (HVCP) is among the novel nonthermal processing techniques gaining attention lately from the scientific community.…”

“…High-voltage cold plasma (HVCP) is among the novel nonthermal processing techniques gaining attention lately from the scientific community. HVCP is comprise of ionised and un-ionised gas produced at either atmospheric or low-pressure environment; the gas contains several active species, namely electrons, free radicals, ions, neutral molecules, reactive oxygen, and nitrogen species, and charged particles [ 16 , 17 , 18 ]. Food materials subjected to HVCP retain and improve their sensitive quality attributes such as nutrients and flavour, it is also harmless to consumers as it did not leave any toxic chemicals on the HVCP-treated foods [ 16 , 19 , 20 ].…”