Example for food emulsions are Butter (W/O), margarine (W/O), mayonnaise (O/W), salad dressing (O/W), milk (O/W), cream (O/W), non dairy creamer (O/W) and ice cream (O/W).Ĥ.5 Functional Attributes of Food EmulsionsĪcceptability of food emulsions is dependent on attributes such as appearance (colour and opacity), texture (viscosity, plasticity, and oiliness) and flavor. Types_of_emulsions.swfįood emulsions may possess solid particles (coagulated protein clumps) and gas bubbles in addition to the two liquid phases. In oil-in-water emulsion the lipid droplets are dispersed in water whereas in water in oil emulsion, the water droplets are dispersed in continuous oil phase. The other type of emulsion is water in-oil type of emulsion and is denoted as W/O. A system consisting of water and non-polar organic liquid, is known as oil- in- water and is denoted by O/W. In food, the rheological property contributes to the mouth feel apart from the ease with which the product pours out of the containers. Stability against creaming relates to shelf life of commercial products. The two important properties of emulsions are the stability against creaming, and the flow properties, in other words their rheology. Various additives which help in the stability of the emulsion.Volume fraction of the oil dispersed in water.Several factors influence the properties of emulsions. Due to the stabilizing effect of these emulsifiers, substances with much larger size than that of ordinary colloids can also be stabilized. Addition of emulsifying agents will reduce the inter facial tension by being adsorbed on the inter phase. The formation of the interface always requires work to be done and as such greater is the interfacial tension, greater is the amount of work required. The two liquids that involve in the formation of emulsion must be insoluble in each other. Emulsification is the process by which emulsions are prepared. In milk and cream, water surrounds droplets of fat (an oil-in-water emulsion). In butter and margarine, fat surrounds droplets of water (a water-in-oil emulsion). Examples of emulsions include butter and margarine, milk and cream. Many emulsions are oil/water emulsions, with dietary fats being one common type of emulsion encountered in everyday life. One liquid (the dispersed phase) is dispersed in the other (the continuous phase).
For an emulsion to be stable, the two liquids must practically be insoluble in each other or only slightly soluble. Knowledge about the behavior and characteristics of an emulsion will help in effective and economic utilization of this component in the preparation of different milk and food products.Īn 'emulsion' is a system in which the dispersion medium and dispersed phase are liquids. This constituent being hydrophobic has to exist in emulsion form. Cut off a piece as needed and use it on hot foods.The characteristic and most useful feature of milk is the presence of a very important constituent namely the fat. (Note: this works if you want to freeze leftover beurre blanc, too. It will still be delicious but more like a compound butter. Instead, simply scoop out a little bit of cold beurre blanc and put it on hot vegetables or fish. It's a warm emulsion and if you reheat it, it will break. To make a day ahead (or for leftover sauce): If you're ok with the fact that the sauce won't really be the same, refrigerate the sauce in a sealed container. If not, add a little cold butter and whisk it in. Or, if your kitchen is warm enough and you have other burners going, you can simply turn off the burner under your sauce and the ambient heat should be enough to keep it intact, provided you whisk it now and then. Keep it over a very low flame and a close eye on it while you are making the rest of the meal, and then whisk in a little stock or cream before serving. To make an hour or so before serving: This requires you to keep the sauce warm, which can be a little tricky because too much heat will break it. Beurre blanc is really meant to be made and used immediately, but you can make it ahead, with a few caveats.
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