Protein oxidation as an integrated aspect of plant protein-based food

Abstract

the protein and extracting soluble components (Johnson et al., 2008). The preparation of soy protein isolate (SPI) from the defatted flour involves separation steps under alkaline or acidic conditions (Alibhai et al., 2006;Lawhon et al., 1981).The final step to prepare both SPC and SPI is spray or freeze drying. About 80% of the proteins in SPI are storage globulin proteins: β-conglycinin, formed by three subunits α, α′ and β; and glycinin, composed of acid and basic subunits linked by disulfide bonds (Nishinari et al., 2017). Typically, the protein yield is around 60% of the protein present in the original soybeans (Johnson et al., 2008). Clearly, the isolation process requires a large amount of water and chemicals (van der Goot et al., 2016). Further, the process conditions applied to isolate proteins generally cause protein denaturation and loss of solubility (Jafari et al., 2016;Schutyser & van der Goot, 2011).Given the inefficiency of current fractionation route, there is an interest arising to develop more energy-efficient methods under less severe conditions, such as aqueous or dry fractionation (Geerts et al., 2018;Xing et al., 2018). Such methods do not yield high protein purity, however, some native components and structures are still present in protein-enriched fractions. Fractions obtained under such mild condition can be beneficial for structuring purposes, for instance when making meat analogues with a soy protein ingredient that intrinsically contains fat (Geerts et al., 2018).Recent research has focused on the use of alternative plant protein sources, such as starch-or oil-rich plants (Schreuders et al., 2019). The use of alternatives could increase the variety of food products on the market, in terms of sensory properties and nutritional value. In addition, the use of alternatives would add value to these other crops. Storage stability Bioavailability Water-insoluble iron Water-soluble iron EncapsulationChapter 1 Jacobsen, 2016;Promeyrat et al., 2011). It has been shown that protein oxidation in meat depends on the temperature and time of the treatment. Some related findings are summarized in Table 1. Protein oxidation increased with temperatures above 100 °C for all meat types. Noticeably, cooking bacon led to higher protein oxidation than other meat products and raw bacon already had a substantial level of oxidation.Protein oxidation often leads to changes in the secondary and tertiary structures of proteins, altering their physical properties, such as solubility and hydrophobicity (Santé-Lhoutellier et al., 2007). Table 1, outline studies showing that cooking meat increased hydrophobicity, due to protein denaturation. In meat products, protein oxidation has been associated with a loss of water-holding and gelling capacities, modification in color and flavor, altered texture, loss of essential amino acids and impaired digestion (

Genetic and molecular understanding for the development of methionine-rich maize: a holistic approach

“…Deb-Choudhury et al (2020) demonstrated that myofibrillar proteins in animal tissue, like myosin, troponin and collagen are highly prone to oxidative protein modifications. Protein oxidation is correlated to the processing severity of food prepration (Estrada, 2019) and need to be taken into account, while accounting for the potential health effects of Met. Recently, He et al (2022) demonstrated that Met oxidation is responsible for metastasis of pancreatic tumor cells.…”