Mayonnaise

Giasson S, Israelaohvili J N and Yoshizawa H 1997 Thin film morphology and tribology study of mayonnaise J. Food Sc/. 62 640-4... 

Lecithin is added to foods such as mayonnaise as an emulsifying agent to prevent the fat and water from sepa rating into two layers... 

Heat Exchangers Using Non-Newtonian Fluids. Most fluids used in the chemical, pharmaceutical, food, and biomedical industries can be classified as non-Newtonian, ie, the viscosity varies with shear rate at a given temperature. In contrast, Newtonian fluids such as water, air, and glycerin have constant viscosities at a given temperature. Examples of non-Newtonian fluids include molten polymer, aqueous polymer solutions, slurries, coal—water mixture, tomato ketchup, soup, mayonnaise, purees, suspension of small particles, blood, etc. Because non-Newtonian fluids ate nonlinear in nature, these ate seldom amenable to analysis by classical mathematical techniques. 

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). 

Time-dependent fluids are those for which structural rearrangements occur during deformation at a rate too slow to maintain equilibrium configurations. As a result, shear stress changes with duration of shear. Thixotropic fluids, such as mayonnaise, clay suspensions used as drilling muds, and some paints and inks, show decreasing shear stress with time at constant shear rate. A detailed description of thixotropic behavior and a list of thixotropic systems is found in Bauer and Colhns (ibid.). 

You may have noticed Ca-EDTA on the list of ingredients of many prepared foods, ranging from beer to mayonnaise. EDTA acts as a scavenger to pick up traces of metal ions that catalyze the chemical reactions responsible for flavor deterioration, loss of color, or rancidity. Typically, Ca-EDTA is added at a level of 30 to 800 ppm. 

A common method for determining the stability of pastry, potato chips, and the like is to place a number of broken pieces of the product in 4-ounce mayonnaise jars with screw tops and store them at room temperature or in the Schaal oven in the absence of light. At regular intervals samples are removed and tested for peroxide content and organoleptic rancidity. 

It should be noted that Cypridina luciferin emits a fairly strong chemiluminescence in aqueous solutions in the presence of various lipids and surfactants, even in the complete absence of luciferase. The luminescence is especially conspicuous with cationic surfactants (such as hexadecyltrimethylammonium bromide) and certain emulsion materials (such as egg yolk and mayonnaise). Certain metal ions (especially Fe2+) and peroxides can also cause luminescence of the luciferin. Therefore, great care must be taken in the detection of Cypridina luciferase in biological samples with Cypridina luciferin. 

Foods such as sugars, colloidal pectins, and mayonnaise emulsions are also prime sources of foaming. 

Lecithin is widely used as an emulsifying agent, allowing oil and water to mix. It is used in ice creams, salad dressings, and cosmetics, and it is the main ingredient in nonstick cooking sprays. Lecithin is the emulsifier in egg yolks that allows the oil and water to mix to make mayonnaise. 

Acetic acid, in the form of vinegar, is used to preserve foods such as pickles. It also provides the sour taste for salad dressings and mayonnaise. 

Emulsifiers are similar to detergents in that one end attracts water while the other attracts fats and oils. They are used to mix oil and water to make products such as mayonnaise, sauces, paints, and medicines. 

An emulsion is a mixture of oil and water. Some emulsions, such as butter and margarine, have tiny droplets of water in the oil. Others, like cream or mayonnaise, are droplets of oil in water. 

Some detergents and surfactants are used as emulsifying agents. An emulsifier keeps oil droplets and water droplets from joining together, so a thick mixture of oil and water will not separate. Examples of emulsions are mayonnaise, butter, cream, homogenized milk, and salad dressings. 

Colloids are classified according to the phases of their components (Table 8.9). A colloid that is a suspension of solids in a liquid is called a sol, and a suspension of one liquid in another is called an emulsion. For example, muddy water is a sol in which tiny flakes of clay are dispersed in water mayonnaise is an emulsion in which small droplets of water are suspended in vegetable oil. Foam is a suspension of a gas in a liquid or solid. Foam rubber, Styrofoam, soapsuds, and aerogels (insu-... 

A foam is a colloid formed by suspending a gas in a liquid or a solid matrix, while a sol is a suspension of a solid in a liquid. Some examples of foams are styrofoam and soapsuds examples of sols are muddy water and mayonnaise. 

JACOBSEN C, HARTVIGSEN K, THOMSEN M K, HANSEN L F, LUND P, SKIBSTED L H, H0LMER G, ADLER-NissEN J and MEYER A s (2001) Lipid oxidation in fish oil enriched mayonnaise calcimn disodium ethylenediaminetetraacetate, but not gallic acid, strongly inhibited oxidative deterioration, J Agric Food Chem, 49, 1009-19. 

The behavior of mayonnaise emulsions when thawed after some exposure to temperatures below room temperature, is considered first. The mayonnaise emulsions are of such a stability that on standing at room temperature for one year or even longer, they show no perceptible oil separation. Such mayonnaise emulsions fall into two categories when thawed back to room temperature after exposure at a given temperature below room temperature those that show no oil separation and those that do show oil separation. Another way to... 

The mayonnaise behavior here discussed is of considerable practical importance, because of the potential spoilage hazard incurred when mayonnaise is placed in transit or in storage in cold climates or at winter temperatures in temperate climates. 

A phenomenon far more intricate than just conventional freezing points is demonstrable, by a consideration of two mayonnaise formulations, identical as to crystalloid content and with the following composition ... 

Notwithstanding the fact that the crystalloids present are dissolved in the case of mayonnaise 2 in some 28% more water than for mayonnaise 1, the breaking temperature of mayonnaise 2 is some 12° F. lower than that of mayonnaise 1. Obviously, were it simply a matter of freezing point lowering, the difference would have to be in the reverse direction. 

Moisture content is but one aspect, albeit an important one, of mayonnaise stability with respect to breaking temperature. 

It is hardly possible to predict that a general theory will ever be evolved which will cover all possible types of industrial emulsions and foams. However, it seems that if the information described were gathered in a systematic fashion, the data could be classified in a logical order for different types of emulsions. Hence, cosmetic-type emulsions, salad dressing, and mayonnaise-type emulsions would each fall into its own individual category. The suggestion therefore is made that a repository of such information be made available to all who are interested. 

Specified processed foods generally known to be made from allergenic ingredients do not require declaration of such ingredients. For example, a sandwich using mayonnaise may mention "mayonnaise" instead of "egg."... 

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