Interfacial and Emulsifying Characteristics of Acid-treated Pea Protein

Abstract

This work presents equilibrium and dynamic aspects for the adsorption at the oil-water interface of pea (Pisum sativum L.) protein isolate (PPI). Dynamic interfacial tension, γ, and surface viscoelasticity modulus, ε, were determined using pendant-drop method. Adsorption kinetics studies revealed that pea proteins adsorb faster at pH 7.0 than at acidic pH (pH 2.4). On the other hand, the measured ε is lower at pH 7.0. This is probably due to fast adsorption, leading to the formation of inhomogeneous film structures. In fact, compared with pHs above the isoelectric point (pI4.3), acidic conditions slow down the adsorption, but the modulus is increased. Pea-protein-stabilized emulsions are more stable to creaming at acidic pH and their particle-size distributions are more homogeneous in these conditions. Effect of pH on interfacial properties and on properties of oil-in-water emulsions stabilized by PPI was interpreted in terms of pea protein solubility, globulin dissociation, and oil-droplet surface electrostatic charge. We propose that at acidic conditions, adsorbed dissociated globulins form stronger and denser viscoelastic networks when adsorbed at oil-water interface. Consequently, the pH-dependence of pea-globulin-stabilized emulsions properties could be of great interest to tune barrier properties of oil/water interfacial membranes for several applications such as encapsulation and controlled release of lipophilic bioactive components within the food, medical, and pharmaceutical industries.

The influence of pea products on the functional properties of frankfurters

“…On the other hand, the water absorbing capacity can be affected by technological factors, including temperature, salt content, and pH, which affect the structure and functionality of proteins and starches (Gharsallaoui et al, 2009). Figure 2 illustrates the temperature effect on the water absorbing capacity of the pea products.…”

“…In the case of starch addition to meat products, it is extremely important to know the gelation temperature of the starch. The gelation temperature of starch must be reached during thermal treatment; otherwise, minced meat products with a poor water-binding capacity and low stability will be produced (Gharsallaoui, Cases, Chambin, & Saurel, 2009;Joly & *Corresponding author. Email: daiva.leskauskaite@ktu.lt CyTA -Journal of Food, 2015Vol.…”

Behaviour of protein-stabilised emulsions under various physiological conditions

“…Pea proteins have been shown to reduce the interfacial tension between the water and oil surfaces by forming a rigid membrane at the oil−water interface [44]. This is due to the surface properties of their constitutive protein fractions, generally classified according to their sedimentation coefficient (S): vicilin (a trimeric 7S globulin) and legumin (a hexameric 11S globulin) [41,45,46]. Soy protein is widely used as an ingredient in food products because of its foaming and emulsifying properties [42,47].…”

The Effect of Various Extracting Agents on the Physicochemical and Nutritional Properties of Pea Starch

“…The rate of starch digestion in legumes is lower than that in the cereals, both in vitro and in vivo, which makes pea starch a better option for use in low glycemic index foods. Besides starch, pea protein contributes substantially to both human and animal nutrition and is known for its non‐allergenic features . Pea protein is rich in lysine, and mainly contains legumin (11S fraction) and vicilin (7S fraction) .…”