Elsevier

Food Hydrocolloids

Volume 99, February 2020, 105333
Food Hydrocolloids

Effect of dry-heat and guar gum on properties of egg white powder: Analysis of forming capacity and baking performance

https://doi.org/10.1016/j.foodhyd.2019.105333Get rights and content

Highlights

  • Dry-heat treatment can decrease particle size of egg white powder (EWP) aggregates.

  • Guar gum (GG) addition increases surface hydrophobicity and viscosity of EWP.

  • Addition of GG to dry heated EWP improved foaming properties significantly.

  • EWP with 10 days' dry-heat and GG addition displays the best baking performance.

Abstract

The effects of dry-heat treatment (75 °C, 0–20 d) and guar gum (GG) composition on foaming properties and baking performance of egg white powder (EWP) were investigated. Rheological measurement showed that both dry-heat treatment and GG addition can improve the viscosity of EWP dispersion. The particle diameter of EWP dispersion decreased after dry-heat treatment, while hydrophobicity increased, indicating that the increased viscosity was caused by the enhanced hydrophobic interaction rather than particle induced steric hindrance. The sample undergoing 10 days of dry heating with GG addition performed the best foaming properties (foaming capacity 9.37 ± 0.26 mL/g and foaming stability 96 ± 1.56%). However, without GG addition, 10 days of dry heating just induced the foaming capacity and stability increasing from 5.17 ± 0.65 mL/g and 42.85 ± 2.90% to 6.96 ± 0.09 mL/g and 64.95 ± 3.04%, respectively. The sample EWP 10 + GG also exhibited the largest cake specific volume and uniform distribution of foams in cross section, which was observed in all three baking systems (low, middle and high sugar). In low sugar system, GG addition induced an increase in cake specific volume from 3.72 ± 0.02 mL/g to 4.55 ± 0.16 mL/g. The results revealed that combining dry-heat and GG addition can more effectively enhance foaming capacity and baking performance of EWP powder, providing guidance for its efficient application in baking industry.

Introduction

Egg white is an important food ingredient due to its high nutrition and excellent foaming properties, which is usually used in aerated foods (such as baking products and puffed food) as foaming agent. With the increase in demand for egg products in food industry, egg white powder (EWP) becomes more suitable for application than fresh eggs and liquid egg white because of the convenience for long-distance transport and long-time storage. However, the foaming properties of egg white powder will deteriorate due to the partial denaturation of protein during spray drying. So, it is critical and urgent for egg processing industry to search for feasible methods to improve foaming properties of egg white powder for efficient application in food production.

Foaming properties can be represented by foam volume, which is associated with the formation and stability of bubble. During the formation of foam, the final foaming capacity is dependent on the adsorption and unfolding rate of proteins at interface (Patino & Pilosof, 2011). During whipping protein molecule adsorbs to air-water interface gradually and unfolds partially at interface, with hydrophobic and hydrophilic groups exposing to gas and liquid phase respectively (Sadahira et al., 2015). The stability of the formed foam is related to the viscoelasticity of the water/gas interface film which is generated by the protein-protein interaction (López-Castejón, Bengoechea, García-Morales, & Martínez, 2016). The appropriate protein transition may accelerate adsorption rate, reduce unfolding time and enhance protein-protein interaction at interface, consequently benefiting to the foaming properties.

Recently, some researches have proved that heat treatment can change protein conformation, and affect its foaming properties by changing the surface charges and hydrophobic groups (Nicorescu, Vial, Talansier, Lechevalier, Loisel, Della Valle et al., 2011; Talansier et al., 2009; Kato, Ibrahim, Watanabe, Honma, & Kobayashi, 1989). It is also pointed out that soluble aggregates may play a vital role in improving foaming properties (Yang & Foegeding, 2010). Besides, the dry-heat treatment of egg white powder is an essential process in the egg industry to simultaneously acquire microbiological safety and excellent functional properties (Lechevalier, Jeantet, Arhaliass, Legrand, & Nau, 2007). Therefore, the foaming capacity of egg white powder could be improved after dry-heat treatment, but it is still poorer in comparison to fresh egg white liquid.

Previous studies indicated that polysaccharides with thickening property usually can be used to enhance foam stability of protein, verified by the decrease of drainage rate (Sadahira et al., 2015). Furthermore, guar gum (GG) has higher viscosity compared to the other gelling polysaccharides owing to its large molecular weight and high hydration ability (Dickinson, 2003). This special property makes it possible for enhancing the foam stability of EWP.

Hence this study investigated the combined effect of dry-heat treatment and GG addition on properties of egg protein (viscosity, surface hydrophobicity, surface charge and particle size) and the corresponding influence on its foaming properties. The key parameters that would affect the foaming properties and whipping performance of EWP were also revealed. And this study has its realistic values in providing a basis for the efficient application of egg white powder in food industry and promoting the development of egg industry.

Section snippets

Materials

Raw egg white powder without dry-heat treatment (Jiangsu Kang De Egg Industry Co., Ltd., Jiangsu, China) and guar gum (Aladdin reagent company of Shanghai, China) were used in this study. Egg white powder is the solid part (with dry matter content around 85% and protein content around 82%) of egg liquid without any additives and guar gum is a straight chain galactomannan with galactose on every other mannose unit with molecule weight of 1–2 × 106 kDa. Cake flour (mainly composed of low-gluten

Average particle size

Protein particle size is an important factor that may affect the adsorption rate of protein molecule to water/air interface during whipping, directly related to foaming properties of protein solution. Fig. 1 showed the effect of dry-heat and GG addition on average particle size of EWP in solutions. As can be seen, with the extension of dry-heat time, the protein particle decreased obviously, reflecting the depolymerization behavior of protein molecules during dry-heat treatment. The aggregation

Conclusions

In this work, the effect of dry-heat treatment and GG addition on physicochemical and foaming properties of EWP was investigated. Dry heating can induce structure transition of EWP, observed by the increase in surface charge and hydrophobicity reflecting the structural expansion of protein. After GG addition, the binding of protein with GG molecule (reflected by the increased size) hindered the charged chain, and promoted the exposure of hydrophobic amino acids and induced to the interaction

Acknowledgments

This work was supported by the National Key Research and Development Program of China (2018YFD0400303). The authors also would like to thank the National Natural Science Foundation of China for support (No. 31501428 and No. 31671809).

References (29)

Cited by (27)

  • Chickpea cooking water (Aquafaba): Technological properties and application in a model confectionery product

    2023, Food Hydrocolloids
    Citation Excerpt :

    For F_AF, bubbles belonging to class 3 and 4 increased their mean area by 19 and 29%, respectively, during 120 min of storage. The addition of GG resulted in a more stable foam as the mean area of bubbles increased by 3.2% for classes 2, 3 and 7% for class 4, respectively; this is consistent with literature data; for instance, Bouyer et al. (2012) mentioned that polysaccharides (e.g., GG) improve foam stability by modifying the viscosity of the aqueous phase; Chang et al. (2020) reported that adding GG to egg white protein resulted in overall increases in viscosity that could slow down gravity drainage and improve foam stability by blocking the flow of the liquid continuous phase. Acidification turned out to be useful in constraining the coalescence of the small bubbles (the increase in the mean area of bubbles was <2% for classes 1–3), however the largest bubbles significantly increased.

  • An overview of the functional properties of egg white proteins and their application in the food industry

    2023, Food Hydrocolloids
    Citation Excerpt :

    Their findings showed that despite foaming properties, lysozyme was more affected by heating than ovalbumin (because of its more rigid structure) while foaming properties of both were enhanced (Hagolle et al., 2000). However, the denaturation of rigid ovalbumin structure to a partially unfolded state or molten globule, due to heat treatment, could enhance its foaming ability compared to its native form (Campbell et al., 2003; Chang et al., 2020). In the case of the mixtures containing EWPs, heat treatment in a dry state (55–65 °C) is commonly used to lower microbial contamination (Lomakina et al., 2006).

View all citing articles on Scopus
View full text