Comparative Study on the Cryoprotective Effects of Three Recombinant Antifreeze Proteins from Pichia pastoris GS115 on Hydrated Gluten Proteins during Freezing

Abstract

During the freezing process, ice crystal formation leads to the deterioration in physicochemical properties and networks of gluten proteins. The cryoprotective effects of recombinant carrot ( Daucus carota) antifreeze protein (rCaAFP), type II antifreeze protein from Epinephelus coioides (rFiAFP), and Tenebrio molitor antifreeze protein (rTmAFP) produced from Pichia pastoris GS115 on hydrated gluten, glutenin, and gliadin during freezing were investigated. The thermal hysteresis (TH) activity and ice crystals' morphology modification ability of recombinant antifreeze proteins (rAFPs) were analyzed by differential scanning calorimetry (DSC) and cryomicroscope, respectively. The freezing and melting properties, water state, rheological properties, and microstructure of hydrated gluten proteins were studied by DSC, low field nuclear magnetic resonance, rheometer, and scanning electron microscopy, respectively. The rTmAFP exhibited strongest TH activity and ice crystals' morphology modification ability, followed by rFiAFP and rCaAFP. The addition of the three rAFPs caused freezing hysteresis and weakened the damage of freezing to the networks of hydrated gluten, glutenin, and gliadin. During freezing, the cryoprotective effects of the three rAFPs on the freezable water content, water mobility and distribution, and rheological properties of hydrated gluten were achieved by protecting these corresponding properties of hydrated glutenin. Among the three rAFPs, rTmAFP was most effective in the cryoprotective activities on hydrated gluten proteins during freezing. The results demonstrate the potential of these rAFPs, especially rTmAFP, to preserve the above properties of hydrated gluten proteins during the freezing process.

Understanding the strengthening effect of curdlan on the quality of frozen cooked noodles: studies on water characteristics and migration during cooking

“…This phenomenon indicated that adding 0.5% curdlan effectively inhibited the increase in freezable water content in FCN during cooking. The freezable water content was highly correlated with the status of binding between water and non‐water components of FCN, where free water was more susceptible to freezing during frozen storage (Liu et al ., 2018). Strong hydrophilicity of curdlan could induce the conversion of free water to bound water (Hernnndez et al ., 2011), which was responsible for the decrease in freezable water when the addition of curdlan at 0.5%.…”

“…As described by Liang et al (2021), relaxation time (T 2 ) reflects water status in components of FCN, and the shorter T 2 , the stronger the interaction between water and components. The integrated area under each peak is proportional to the corresponding number of protons (Liu et al, 2018), and the different proportions of T 2 (T 21 , T 22 and T 23 ) are summarised in Table 1.…”

Effect of antifreeze proteins on the freeze-thaw cycle of foods: fundamentals, mechanisms of action, current challenges and recommendations for future work

“…AFPs are also known as ice structuring proteins (ISPs), ice-binding proteins (IBPs) or thermal hysteresis proteins (THPs) ( Liu et al., 2018b ; Ding et al., 2020 ; Eskandari et al., 2020 ). They are peculiar compounds that adhere to ice, specifically at the water-ice interface ( Chen et al., 2021a ).…”

Phase change and crystallization behavior of water in biological systems and innovative freezing processes and methods for evaluating crystallization

“…AFPs not only decreased drip loss but also preserved the color, total anthocyanin, and antioxidant content of frozen cherries [185]. AFPs have also been investigated during freezing food samples, including gluten proteins [186], dough [187,188], starch solution, milk, and orange juice [189], ice cream [190,191], pasta sauces [192], and carrot [193].…”