Protein-hydrocolloid interactions

Schaink, H.M., Smit, J.A.M. (2007). Protein-polysaccharide interactions the determination of the osmotic second virial coefficients in aqueous solutions of p-lactoglobulin and dextran. Food Hydrocolloids, 21, 1389-1396. 

Tolstoguzov, V.B. (1991). Functional properties of food proteins and role of protein-polysaccharide interaction. Food Hydrocolloids, 4, 429 168. 

In whippable emulsions with a high fat content, the air-water interface of the foam after whipping is dominated by adsorbed deproteinated fat globules. In whippable emulsions with a low fat content other foam stabilizing mechanisms come into play, such as protein-hydrocolloid and protein-emulsifier interactions. The former subject may be studied by... 

Syrbe, A., Bauer, W.J., and Klostermeyer, H. (1998). Polymer science concepts in dairy systems An overview of milk protein and hydrocolloid interaction. Int. Dairy J. 8, 179-193. 

Therefore, to understand the behavior of food emulsions, we need to know as much as possible about these types of emulsifiers, because fliey may not behave exactly similarly to classical small-molecule emulsifiers. For example, phospholipid molecules can interact with each other to form lamellar phases or vesicles they may interact with neutral lipids to form a mono- or multi-layer around the lipid droplets, or they may interact with proteins which are either adsorbed or free in solution. Any or all of these interactions may occur in one food emulsion. The properties of the emulsion system depend on which behavior pattern predominates. Unfortunately for those who have to formulate food emulsions, it is rarely possible to consider the emulsion simply as oil coated with one or a mixture of surfactants. Almost always there are other components whose properties need to be considered along with those of the emulsion droplets themselves. For example, various metal salts may be included in the formulation (e.g. Ca " is nearly always present in food products derived from milk ingredients), and there may also be hydrocolloids present to increase the viscosity or yield stress of the continuous phase to delay or prevent creaming of the emulsion. In addition, it is very often the case, in emulsions formulated using proteins, that some of the protein is free in solution, having either not adsorbed at all or been displaced by other surfactants. Any of these materials (especially the metal salts and the proteins) may interact with the molecules... 

Many food formulations contain mixtures of surfactants (emulsifiers) and hydrocolloids. Interaction between the surfactant and polymer molecule plays a major role in the overall interaction between the particles or droplets, as well as the bulk rheology of the whole system. Such interactions are complex and require fundamental studies of their colloidal properties. As discussed later, many food products contain proteins that are used as emulsifiers. Interaction between proteins and hydrocolloids is also very important in determining the interfacial properties and bulk rheology of the system. In addition, the proteins can also interact with the emulsifiers present in the system and this interaction requires particular attention. 

Protein-polysaccharide interactions play a significant role in the structure and stability of many processed foods [192]. The control of these macromolecular interactions is a key factor in the development of novel food processes and products as well as in the formulation of fabricated products. Much has been written on the possible interaction between the proteins and hydrocolloids in model and real systems, but very little advantage has been taken of these studies in designing... 

For a colloidal system containing a mixture of different biopolymers, in particular a protein-stabilized emulsion containing a hydrocolloid thickening agent, it is evident that the presence of thermodynamically unfavourable interactions (A u > 0) between the biopolymers, which increases their chemical potentials (thermodynamic activity) in the bulk aqueous phase, has important consequences also for colloidal structure and stability (Antipova and Semenova, 1997 Antipova et al., 1997 Dickinson and Semenova, 1992 Dickinson et al., 1998 Pavlovskaya et al., 1993 Tsap-kina et al., 1992 Semenova et al., 1999a Makri et al., 2005 Vega et al., 2005 Semenova, 2007). 

Poncet-Legrand, C., Edelmann, A., Putaux, J.-L., Cartalade, D., Sarni-Manchado, R, Vernhet, A. (2006). Poly(L-proline) interactions with flavan-3-ols units Influence of the molecular structure and the polyphenol/protein ratio. Food Hydrocolloids, 20, 687-697. 

Badii, F. and Howell, N. K. (2005). Fish gelatin structure, gelling properties and interaction with egg albumen proteins. Food Hydrocolloids 20,630-640. 

The hurdles affecting the shelf life of foods also influence other food properties, including texture. The effects of several physical, chemical, and mechanical treatments should be carefully considered in developing new processes and products. It is not enough to describe the composition of a food product and to determine the conditions and types of unit operation necessary to achieve the required quality. How the major food components, such as water, salt, hydrocolloids, starches, lipids, proteins, flavors, and additives, interact with each other and affect the product quality with respect to microstructure, texture, and appearance should be examined. 

Berli, C.L.A., Deiber, J.A., and Anon, M.C. Connection between rheological parameters and colloidal interactions of a soy protein suspension, Food Hydrocolloids, 13, 507,1999. 

In fresh cheese elaborated with pectin (Figure 2.12), the hydrocolloid is observed to form a network that interacts not only with the protein matrix, but also with the protein shell snrronnding fat globules (Hernando et al., 1998). 

Mannoproteins are complex hydrocolloids released from yeast cell walls during autolysis (Goncalves et al., 2002 Charpentier et al., 2004). According to Feuillat (2003), mannoproteins are important to wine quality as these contribute to protein and tartrate stability, interact with aroma compounds, decrease the astringency and bitterness of tannins, and increase the body of wine. For instance, Dupin et al. (2000) reported that mannoproteins prevent protein haze formation. Using a model wine. Lubbers et al. (1994) noted that yeast cell walls bound volatile aroma compounds, especially those more hydrophobic, and could potentially change the sensory characteristics of wines through losses of these aromas. 

When we consider the other chemical interactions (e.g., flavor interactions with carbohydrates, proteins, and high potency sweeteners), we understand that interactions take place but they are so complex that we cannot model them to even attempt to make corrections in the flavorings. Thus, we know that a substitution of one protein for another or one hydrocolloid for another will affect the flavor of a product, but we cannot quantify these effects and therefore make changes in flavor formulations. At this time, we can only expect effects and attempt to deal with them in a less than scientific manner, i.e., empirical efforts. 

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