The smell, taste and feel of a freshly baked cookie are particularly powerful; it is linked with fond memories and mouth watering for many people all over the world. What the average person may not know is that what makes a cookie appetizing is due to chemical reactions, many of which are facilitated by the inclusion of eggs as an ingredient in the baking process. However, every year more and more people are avoiding eggs in their diet for a variety of reasons. The vegan lifestyle is becoming more and more affordable and mainstream. Fears (the rationality of which is still strongly debated) of an increase in cholesterol levels due to egg consumption also contribute. Additionally, egg allergy is the second most common allergy in children behind dairy (FARE). How to create a familiar and delicious cookie without using eggs? This article seeks to discern the chemical properties of eggs, their specific functions in the cooking process, identify certain substitutions that serve similar purposes, and discover how they chemically fulfill their role. Say no to plagiarism. Get a tailor-made essay on "Why violent video games should not be banned"? Get an original essay In an average cookie, eggs may seem to make up only a small proportion of the ingredients by volume, but their chemical properties affect how of which all the other ingredients work together to create the final product. So, what is an egg? The average chicken egg regularly used in American baking is composed of a hard outer shell that can come in a variety of shades, white and yellow. After breaking the shell of the calcium carbonate (CaCO3), the baker first comes into contact with the white, or albumen, which is approximately 90% water, with the remainder made up of seven major proteins (Evanhoe 2006). The most important of them is ovalbumin, which nourishes and strengthens the immunity of the unborn chick. Conalbumin is necessary to bind iron. About 2% of the protein in egg white is ovomucin, responsible for its familiar thickness and gooey consistency. The pH of the albumen of a freshly laid egg is approximately 7.6 and rises to 9.2 after several days of storage. Albumin adheres more strongly to the inside of the eggshell at a lower pH. The yolk can be yellow or almost red due to the carotenoid pigments lutein and zeaxanthin. The yolk contains approximately 33% lipids and 17% proteins. It contains a significant amount of fatty acids (including oleic acid, palmitic acid and linoleic acid) and cholesterol. It also contains fat-soluble vitamins A, D, E, and K, as well as lecithin, a compound that contains many different phospholipids. Lecithin is notable for being an emulsifier, stabilizer and surfactant. It is extracted from eggs for many uses, including pharmaceutical purposes and in some cosmetics (Pyler 2010). These same properties also make eggs valuable in baking. When you beat eggs with flour, butter, and other cookie ingredients, it may seem like the goal is only to combine elements to make a more consistent mixture, but in reality, the chemistry of cookies is taking place. Already. Eggs help bring the water and fat phases together to give a creamier, smoother texture (Indrani 2008). The lecithin in the yolk covers the air bubbles that form during beating, preventing them from collapsing when heated. These grease-covered CO2 air bubbles increasethe softness of the final product and contribute to its rise, structure and shape. Lecithin and other long chains of amino acids in the egg act as binders to hold ingredients together. Once baked goods reach an internal temperature of approximately 176 degrees F, the risen dough assumes its permanent shape as the egg proteins coagulate, the starch granules absorb water and form a gel, and the gluten denatures and loses its elasticity. The final texture is fixed during cooking by the coagulation of egg and flour proteins (Connelly2010). One of the most important chemical reactions in baking is the Maillard reaction, commonly called simply "browning" but responsible for the good golden brown color of baking and the production of hundreds of roasted and savory flavor compounds. The right temperature is necessary for the sugars and proteins on the surface of baked goods to combine and rearrange into proper compounds. The reactive carbonyl group of the sugar interacts with the nucleophilic amino group of the amino acid. This process accelerates in an alkaline environment because the amino groups do not neutralize each other. At a higher pH, the amine group is a better target for reducing sugars. Egg wash applied to yeast bread or other baked goods increases the surface pH to further encourage the Maillard reaction. The content of fat, sugar, albumen and other proteins offers almost unparalleled potential in cooking to increase the potential of other ingredients around them by thickening, binding, leavening, providing structure, contributing moisture and encouraging Maillard reaction (Gillespie 2019). ). Additionally, eggs thicken and smooth custards and puddings and create a stable foam at high temperatures that makes delicate choux pastry and meringues possible (Tamanna et al 2015). Given the unique structure and contents of an egg, it's easy to imagine how difficult it would be to replicate in baking. So what can you do if you're avoiding eggs for ethical, dietary, or allergy reasons? The good news is that all hope is not lost. Several items that function similarly to eggs in baked goods have been identified, and there are a few commercially available products on the market called egg substitutes. However, the bad news is that there is no item on earth that can do exactly what an egg can do while being vegan or allergen-free. But, if you can identify the primary physical and chemical property that an egg is intended to impart to your recipe, there are specific alternatives that can easily and often indistinguishably replace it. The emulsifying properties of eggs are the easiest to imitate (McVean 2018). These are recipes in which the egg is used to stabilize a mixture between two immiscible liquids, such as the process of making mayonnaise or the creaming of fat and sugar when preparing pound cake. The main factor affecting emulsifiers is concentration, with diluted ingredients emulsifying poorly. The most ideal substitution for eggs in emulsions is flaxseed. The outermost layer of flaxseed, the epidermis, contains mucilaginous material that makes up about 8% of the flaxseed's weight. This mucilage, or gel, once extracted, can be easily used as an egg substitute and is suitable for many vegan baking applications. How? Flax gel is a hydrocolloid composed of polysaccharides. While eggs themselves contain almost no carbohydrates, longSimple sugar chains found in flax gel can form extensive networks similar to those in denatured egg proteins (Noren). While other plants such as chia seeds, aloe vera, okra, and even some basil seeds also contain polysaccharide gels, they can in some cases be prohibitively expensive and in other cases impart undesirable flavors to the final product. Of course, flax gel can't do everything an egg can. It will not succeed in replacing eggs in extremely light desserts like angel food cake, choux pastry or popovers. In cakes, flax gel would probably not be a good substitute, as the mucilage can coat the gluten and gliadin in the flour, effectively blocking the formation of gluten bonds, so it will not create structure like would an egg (Hagedorn 2019). However, in things like muffins, bread, and cookies, a "flax egg" will work well. There are several methods for creating a “flax egg.” The easiest is to grind whole flax seeds in a blender or spice grinder, then 1 tablespoon of ground flax meal in 3 tablespoons of water. Letting this mixture sit for 10 minutes will release the mucilage. Warmer water speeds up this process. The whole thing can be added in recipes in place of an egg, in recipes where color and texture will not be an issue. Miyoko Schinner, famous vegan pastry chef and CEO of Miyoko's Creamery, is credited with pioneering an alternative, more complex method that should be used in cases where the aforementioned color and texture would not do the trick (Hagedorn 2019). Instead of grinding flax seeds, one can boil 5 tablespoons of flax seeds in 3 cups of water for about 20 to 25 minutes. Not only does this method extract all the mucilage from the shell, but boiling some of the water allows the mixture to condense somewhat. Then, using a fine sieve, filter the mucilage from the water and let it cool. Due to its viscosity, it can be difficult to measure, but three tablespoons is the effective conversion rate for replacing one egg. Coagulation is a little more difficult to reproduce perfectly. This property allows eggs to bind foods together, thicken preparations, such as custards, omelettes and puddings, or positively benefit the crumb and structure of baked goods (Pyler and Gorton 2010 ). In things like cornbread, quick breads or vegan burgers, for example, a common recommendation is to add additional starch such as arrowroot powder, potato starch or tapioca starch, as well as a little neutral oil to add fat. Another common recommendation is to add fruit puree like mashed banana, applesauce, mashed potato, mashed pumpkin or squash. Here a lot depends on the desired flavor of the final product. Applesauce adds very little flavor and texture to baked goods, while a little banana can overpower a recipe. The egg substitute chosen varies greatly depending on the recipe and the baker's personal preferences. Until recently, the most difficult property to replicate for a vegan or egg-avoiding pastry was foam. You can't make meringue with a banana. An ingredient's ability to foam depends on the beating method, temperature, pH and water content. Some foods like soy milk or whey protein can create foam, but these foams are not stable at high/29553544.