*3.2. Thermal Treatment*

The conformation and aggregation behavior of proteins are greatly influenced by heat treatment, resulting in modified functional properties [15]. The protein molecules tend to unfold the globular structure and expose the hydrophobic groups. It has been reported that the emulsions stabilized by 75 ◦C; heated soy protein showed lower emulsion droplet size compare to the unheated soy protein. The heated soy protein showed a

higher extent of adsorption at the interface, with a higher ratio of β-conglycinin among the absorbed protein. The acidic and basic subunits of glycinin remained in the serum phase in similar amounts in these emulsions as in the unheated samples. Heat-induced dissociation of β-conglycinin has previously been shown to result in the formation of soluble complexes [16,17]. However, high-temperature treatment (95 ◦C for 15 min) might cause dissociation and denaturation of both β-conglycinin and glycinin, resulting in the formation of soluble aggregates between the basic subunit of glycinin and the β-subunits of β-conglycinin. The majority of the aggregates formed during heating adsorb at the interface during homogenization, which could explain the decreased emulsion stability [15].
