Salad cream

Sodium carboxymethylcellulose is acceptable for use in food, and is employed in a variety of foodstuffs. It is used to prevent formation of ice crystals in ice creams to control the consistency of cheese spreads to stabilise the emulsions needed in salad creams and to thicken toothpaste. 

The possibility of using ultrasound to measure droplet sizes in real foods has so far been demonstrated for casein micelles [69], salad creams [35] and milk globules [70]. However,... 

Set up a circus of gels, sols, emulsions and foams, e.g. jelly , milk, pumice stone, polyurethane foam, bread, emulsion paint, cola, hair cream, aerosol dispenser, salad cream. A silica gel can be made from sodium silicate and hydrochloric acid. Classify the examples according to type of colloidal system. 

The use of surfactants in the food industry has been known for centuries. Naturally occurring surfactants such as lecithin from egg yolk or soybean and various proteins from milk are used for the preparation of many food products, such as mayonnaise, salad creams, dressing, and desserts. Polar lipids such as monoglycerides have been introduced as emulsifiers for food products. More recently, synthetic surfactants such as sorbitan esters (Spans) and their ethoxylates (Tweens), sucrose esters, have been used in food emulsions. It should be mentioned that the structures of many food emulsions is complex, and in... 

Several industrial systems involve emulsions, of which the following are worthy of mention. Food emulsions include mayonnaise, salad creams, deserts, and beverages, while personal care and cosmetics emulsions include hand creams, lotions, hair sprays, and sunscreens. Agrochemical emulsions include self-emulsifiable oils that produce emulsions on dilution with water, emulsion concentrates with water as the continuous phase, and crop oil sprays. Pharmaceutical emulsions include anaesthetics (O/W emulsions), hpid emulsions, and double and multiple emulsions, while paints may involve emulsions of alkyd resins and latex. Some dry-cleaning formulations may contain water droplets emulsified in the dry cleaning oil that is necessary to remove soils and clays, while bitumen emulsions are prepared stable in their containers but coalesce to form a uniform fihn of bitumen when apphed with road chippings. In the oil industry, many crude oils (e.g.. North sea oil) contain water droplets that must be removed by coalescence followed by separation. In oil slick dispersion, the oil spilled from tankers must be emulsified and then separated, while the emulsification of waste oils is an important process for pollution control. 

Thixotropic liquids, e.g. paints, tomato ketchup, salad cream. Here the apparent viscosity reduces with time as the material is sheared at a constant shear rate Figure I.JI). Usually after a large time of shearing, an equilibrium apparent viscosity is reached. If the shearing is now stopped the... 

Sorbic acid (2,4-hexadienoic acid) is used in salad cream, wine and baked goods as an antimycotic. It is effective in relatively acidic products with a pH of usually less than 4.8. 

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... 

The determination of droplet-size distributions in water-in-oil or oil-in-water emulsions by pulsed-gradient diffusion measurements is now a routine industrial method for monitoring the quality of food emulsions such as mayonnaise and salad creams. The method was first described in a classic paper by Packer and Rees (see Further reading section) and subsequently developed into a rapid analytical method. The theoretical model assumes spherical droplets and a log-normal size distribution, but other distributions have been considered. The MRI generalization of the method to spatially dependent droplet-size distributions in emulsions undergoing coalescence and/or phase separation has yet to be implemented, although a spatially dependent study of emulsion crystallization has been reported. 

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