Wednesday, June 5, 2019

Effect of Whipped Egg Whites on Soufflé Volume

Effect of Whipped Egg Whites on Souffl VolumeR. ArduraTHE EFFECT OF WHIPPING EGG WHITES OVER ITS LEAVENING CAPACITY IN SOUFFLESINTRODUCTIONWe may all told agree with the grand statement Nicholas Kurti said over his presentation The Physicist in the KitchenIt is a sad reflection on our civilization that while we tail residue and do measure the temperature in the atmosphere of Venus, we do not recognise what goes on inside our souffls (Barham, 2001).Souffls, sponge cakes, meringues, and bread atomic number 18 some examples of bake foams. Foams allow the diner a better perception of the texture of a dense mass in the mouth and enhance the perception of odors (This, 2009). Understanding how foams work on a lower floor dynamic conditions is crucial for any chef to achieve a better end product and give the consumer a greater enjoyment.Egg innocences are commonly utilize as an aerating agent because of its foaming properties. Their foam assists in the leavening process, although t he actual leavening agent is air. Foam simply allows air to be incorporated into cook goods (Figoni, 2011). The end goal is to capture and retain as much air inside the souffl to achieve an airy, light and delicate end product.Foams are a colloidal system of a gas dispersed into a still free burning phase (Pawel et al, 2014). In the case of souffls, the continuous phase is water with egg white proteins, lipids and carbohydrates dissolved in itwhich will strengthen the dispersing medium, and the dispersed phase is air (McWilliams, 2012). Oxygen, nitrogen, carbon dioxide, and some of the other components of air are mostly hydrophobic. In other words, air can dissolve in water but only in tiny amounts (MyHrvold, 2011).The mechanical action of beating pushes air bubbles into the continuous phase of the forming foam while the protein of the egg whites unfold to form a monolayer film at the surface of the air pushed inside. This stage of foam forming is called absorption ( chromatic, 1 981). The deliquescent part of the egg white proteins will be attracted and bound with water and any hydrophilic component present in the solution, while the hydrophobic end will be oriented inwards surrounding the gas phase and stabilizing the bubble (MyHrvold, 2011).When talking about foams in sustenance products, it is of interest to know the foams stableness and volume. Any solids, such as sugar, present in the continuous phase of foam add viscosity to the liquid base. dissimilar levels of viscosity, or resistance that a fluid poses to shear forces, changes the mouth-feel of the product and duration of the foam. In general, the more viscous a liquid is, the longer its bubbles last (Pugh, 1996). We should alike keep in mind that a greater resistance to shear forces means a smaller increase of volume from air expansion. Therefore, the recipe apply in this study has minimal foaming agents and foaming stabilizers to ensure that the outcome truly reflects the impact of the whipp ing stage on the increased volume and stability of the souffl.The rate and extent in which albumin unfolds to form a film at the surface of the gas, also called the absorption rate, increases as shear force is use to the egg white when beaten (Damodaran and Song, 1988). As protein unfolds and secures gas to form new bubbles the boilers suit volume of the solution grows. Foam becomes opaque and can be pulled into semisoft peaks. While some bubbles collapse, others are surrounded with a second monolayer. The second film covers any coagulated regions, caused by over beaten proteins, from the first monolayer (Cherry, 1891). The bubbles progressively become smaller and foam gets tighter until stiff peaks are formed (McWilliams, 2012). This is usually the stage egg whites are brought to for making souffls. It is a common belief that manner of speaking the egg white foam to this stage will make a more stable souffl.The normal pH value for egg whites is from 7-8, but as they age their pH goes up. However, the rate and battlefield to which proteins unfold and reposition at the interface is conditional to the proteins inter molecular limitation to form new bonds. The overall egg white foam stability is optimal at or upright the isoelectric pH of albuminpH5.5 (Cherry, 1981). This is due the convex shape bubbles take near the pI of albumin, which exhibit a slower liquid drainage rate than decay from gas diffusion and disproportionation (Damodaran, 1994). As a result of less liquid drainage the foam films remain thick enabling dry foams of high stability to be formed (Malysa and Lunkenheimer, 2007). Furthermore, the addition of an acid boosts the number of free-floating hydrogen ions in the egg white slowing down disulfide bonding and exposing hydrophobic regions that result in further adsorption sites (Murray, 2007). In order to generate the same variables for this study, all egg whites were titrated to pH 5.5 creating a more suitable protein conformation for entr apping and holding air dispersions.Foam will start to form when the number of new and salt a focus bubbles exceeds the number of rupturing ones. The stability of foam does not only depend on the solutions composition but also the state of the bubbles adsorption layers (Malysa and Lunkenheimer, 2007). Most studies focus on the stability of foams under(a) static conditions where a tight bubble network and high stability are formed. Considering that in the souffl production process foam is subject under dynamic conditions, surface elasticity may become of significant importance when analyzing foam expansion and stability on such systems.In addition, even though it would seem logical that a highly flexible unfolded protein would cover a greater surface area than a compact folded protein, Damodaran and Song found that one of albumins folded intermediates occupies a greater surface area (Damodaran and Song, 1988). Therefore, in order for a protein to entrap the maximum amount of gas in foam and exert the most favorable reduction of the surface tension, it should be processed (whipped) until an optimum degree of unfolded and folded coils are achieved (Damodaran, 1989).The physical law that animates the phenomenon occurring in a souffl was discovered by the French scientist and balloonist J. A. C. Charles. Charles law states, the volume occupied by a given weight of a given gas is proportional to its temperature (McGee, 2004). Some may conclude that the greater amount of air bubbles trapped the greater the volume will raise as the souffl is baked. Others may believe that it does not matter the stage the egg white has been whipped to because gas will always expand a fixed amount. However, bearing in mind Damodaran and Songs discovery and the assumption that surface elasticity could play a determining roll on foams expansion and stability under dynamic conditions, there might be the possibility to believe that stiff peak is not the optimum stage at which the egg white must(prenominal) be whipped to achieve the maximum final volume in souffls.This study will focus on the effects different stages of whipped egg white foams make water on the final volume of souffls. After this study a chef will know the best possible utilization of egg whites for souffls and other food preparations where egg whites act as a leavening agent. Learning about egg whites surface rheology through measurements recollected over a get of timescales will help to understand how the protein structure on whipped egg whites relate to the final volume of souffls. It may also suggest a better way to produce other backed foam products as sponge cakes, meringues and bread.WORKS CITEDBarham, P. (2001). The Science of Cooking. Berlin, Germany Springer-Verlag GmbH.Figoni, P. (2011). How Baking Works (3rd ed, pp. 258, 267, 300 303) Hoboken, NJ John Wiley Sons.McGee, Harold (2004). On nourishment and Cooking The Science and Lore of the Kitchen (1st ed.), Egg Foams (pp.109-113). pa rvenu York, NY Scribner.McWilliams, Margaret (2012). Foods Experimental Perspectives. (Seventh ed., pp. 113, 114, 116, 384-387, 412). New Jersey Pretince Hall.MyHrvold, N., Young, C. Bilet, M. (2011).The Modernist Cuisine The Art and Science of Cooking(1st ed., Vol 4, pp. 74, 240-255). Bellvue, WA The Cooking Lab.This, H. (2009), Science of the Oven. New York, NY Columbia University Press.Pawel, P., et al. (2014). The Physical and Linear Viscoelastic Properties of Fresh Wet Foams Based on Egg White Proteins and Selected Hydrocolloids. Food Biophysics, 976-87Cherry, J. P. (1981). Whipping and Aeration. In Cherry McMaters (Eds.), Protein Functionality in Foods (pp. 150-153). American Chemical Society USA.Damodaran, S (1994). Protein functionality in food systems. In N. S. Hettiarachchy G. R. Zeigler (Eds.), Structure-Function Relationship of Food Proteins (pp. 15-17). Chicago, IL Institute of Food Technologists.Damodoran, S. (1989) Interrelationship of molecular and functional prop erties of food proteins. In J. E. Kinsella W. G. Soucie (Eds.), Food Proteins (pp. 21-22). Champaign, IL The American Oil Chemists Society.Damodoran, S. and Song, K. B. (1988). Kinetics of absoption of proteins at interfaces Role of protein conformation in diffusional adsorption. Biochim. Biophys. Acta 954253.Malysa, K. and Lunkenheimer, K. (2007). Foams under dynamic conditions. current Opinion in Colloid Interface Science, 13 (2008), 150-162. doi10.1016/j.cocis.2007.11.008Murray, B. S. (2007) Stabilization of bubbles and foams. Current Opinion in Colloid Interface Science. 12 (2007), 232-241. doi10.1016/j.cocis.2007.07.009

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