Mayonnaise rheology

Dispersed Systems. Many fluids of commercial and biological importance are dispersed systems, such as soflds suspended in Hquids (dispersions) and Hquid-Hquid suspensions (emulsions). Examples of the former include inks, paints, pigment slurries, and concrete examples of the latter include mayonnaise, butter, margarine, oil-and-vinegar salad dressing, and milk. Blood seems to fall in between as it is a suspension of deformable but not hquid particles, and it does not behave like either a dispersion or an emulsion (69) it thus has an interesting rheology (70). 

D Peressini, A Sensidoni, B de Cindio. Rheological Characterization of Traditional and light mayonnaises. J Food Eng 35(4) 409-417, 1998. 

A typical characteristic of many food products is that these are multi-phase products. The arrangement of the different phases leads to a microstructure that determines the properties of the product. Mayonnaise, for example, is an emulsion of about 80% oil in water, stabilized by egg yolk protein. The size of the oil droplets determines the rheology of the mayonnaise, and hence, the mouthfeel and the consumer liking. Ice cream is a product that consists of four phases. Figure 1 shows this structure schematically. Air bubbles are dispersed in a water matrix containing sugar molecules and ice crystals. The air bubbles are stabilized by partial coalesced fat droplets. The mouthfeel of ice cream is determined by a combination of the air bubble size, the fat droplet size and the ice crystal size. 

J. Plucinski, R.K. Gupta and S. Chakrabarti, Shear and Extensional Rheology of Mayonnaises, presented at the Second International Conference on Extensional and Shear Flow of Polymer Fluids from the Solution to the Melt, St. Andrews, Scotland, June 19-22, 1994. 

Food products must have appropriate texture properties. For example, it is important that mayonnaise products have thick and creamy textures, but not too high a viscosity. The rheological properties depend on their composition, such as the concentration of oil droplets or the concentration of thickening agents. 

Sathivel, S., Bechtel, P. J., Babbitt, J. K., Prinyawiwatkul, W., and Patterson, M. 2005. Functional, nutritional, and rheological properties of protein powders from arrow-tooth flounder and their application in mayonnaise. Food Eng. Phys. Prop., 70, 57-63. 

A model to study thixotropic behavior of foods exhibiting yield stress was devised by Tiu and Boger (1974) who studied the time-dependent rheological behavior of mayonnaise by means of a modified Herschel-Bulkley model ... 

Other relevant studies on physical properties of emulsions are those of McClements et al. (1993), Dickinson and Pawlowsky (1996), Dickinson et al. (1996), and Demetriades et al. (1997). The application of nuclear magnetic resonance (NMR) technique (Simoneau et al., 1993) and ultrasonic spectroscopy (Demetriades et al., 1996) to study the stability of emulsions were discussed. The rheological behavior of salad dressings and mayonnaises that are emulsions will be discussed in Chapter 5. 

Rheological properties of mayonnaise have been studied using different rheological techniques steady shear rate-shear stress, time dependent shear rate-shear stress, stress growth and decay at a constant shear rate, dynamic viscoelastic behavior, and creep-compliance viscoelastic behavior. More studies have been devoted to the study of rheological properties of mayonnaise than of salad dressings, probably because the former is a more stable emulsion and exhibits complex viscous and viscoelastic rheological behavior. 

Because of the existence of yield stress as well as time-dependent rheological behavior of mayonnaise, it would seem reasonable to expect that traditional relationships between steady shear properties on one hand and small amplitude dynamic properties on the other that were found for polymeric liquids will not hold for mayonnaise. Bistany and Kokini (1983) showed that the Cox-Merz rule and other relationships at low shear rates and frequencies did not hold for mayonnaise and... 

Kiosseoglou, V. D. and Sherman, P. 1983. Influeneeof egg yolk lipoproteins on the rheology and stability of o/w emulsions and mayonnaise 1. Viscoelasticity of groundnut oil-in-water emulsions and mayonnaise. J. Texture Stud. 14 397-417. 

Table 5-L Rheological Properties of Mustard, Mayonnaise, Oils and Fats ...

Mayonnaise and ice cream both have a yield stress, which is produced in these foods by droplets and air bubbles that must deform if flow is to occur. Another food with a yield stress is mustard, it is neither an emulsion nor a foam, but a suspension or paste, containing particles 30 pm or so in diameter that attract each other and form a weak network (Gerhards and Schubert 1993). Mustard is made by simply grinding mustard seeds, together with vinegar, salt, spices, and water, into a mash. The grinding releases oils that impart to mustard its distinctive flavor. The rheology of particulate suspensions is covered in Chapter 6. 

A number of models have been developed to describe transient viscoelastic behavior and one must have at hand carefully obtained rheological data in order to test the applicability of the models. Another example of the applicability of models to viscoelastic data is the study of Leppard and Christiansen (1975) in which the models proposed by Bogue and Chen, Carreau, and Spriggs were evaluated. In the case of foods, the empirical models have been developed to describe the transient data on stick butter, tub margarine (Mason et al, 1982), canned frosting (Kokini and Dickie, 1981 Dickie and Kokini, 1982), and mayonnaise (Campanella and Peleg, 1987c). 

Ma, L., and Barbosa-Canovas, G. V. (1995a). Rheological characterization of mayonnaise. 

Part I. Slippage at different oil and xanthan gum concentrations. J. Food Eng. 25,397-408. Ma, L., and Barbosa-Canovas, G. V. (1995b). Rheological characterization of mayonnaise. Part II. Flow and viscoelastic properties at different oil and xanthan gum concentrations. J. Food Eng. 25, 409-425. 

Moros, J.E., Franco, J.M. and Gallegos, C. (2002) Rheological properties of cholesterol-reduced, yolk-stabilized mayonnaise. /. Am. Oil Chem. Soc., 79,837. 

Knowledge of the rheological properties of food pastes, slurries and sauces, such as ketchup, mayonnaise and salad creams, is important both for quality assurance and for optimizing industrial flow and mixing processes. Unfortunately, many food slurries and pastes are opaque and do not lend themselves to flow studies with conventional techniques such as laser Doppler anemometry. Moreover, conventional rheological measurements are model-dependent in that it is necessary to fit the data by assuming a function relationship between the stress and strain (or strain rate) and to assume a set of boundary conditions (such as slip or stick) at the fluid-container... 

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