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Message: [QUOTE="Norcalbaker59, post: 42347, member: 2340"] @cahoots, you know how I go on about how there is sooo much bad info on the internet. Another pet peeve of mind is beating egg whites, and in particular egg whites for meringue. Whipping egg whites is all about stability. The egg white is about 90% water and 10% protein When you beat egg white you physically cause the denaturation of protein: long chain amino acids unfurl from a somewhat spherical shape. This exposes various amino acids that are either hydrophilic (absorbs water on a molecular level) or hydrophobic (repels water on a molecular level). If whipped correctly, the hydrophilic amino acids will form what is called ionic bonds, created by electrically charged molecules, that bind to water molecules. These bonds are the best bonds as they create a voluminous, silky, and moist meringue. Remember, water molecules like to bond to each other. But as you beat more and more air into the egg whites it separates the water molecules from each other. This forces the water molecules out of the network of amino acids (proteins), water, and air bubbles. If too much air is beaten in, it eventually destabilizes the entire network of molecules, and allows disulfide bonds form. These are bonds between the amino acids that have sulfurs. When the water is squeezed out and these really tight bonds form between the sulfur animo acids form you get dry egg whites that are full of gritty tiny white specks. So there are two types of bonds that can occur in whipped egg whites: [LIST] [*]iconic bonds (perfectly beaten egg whites) [*]disulfide bonds (over beaten egg whites) [/LIST] The iconic bonds are not stable. To stabilize the iconic bond you must do three things: 1. add an acid 2. add sugar at the correct time and slowly 3. gradually beat egg whites from low speed to high speed Acid: people tell you to add an acid, but never explain why. An acid like cream of tartar is potassium hydrogen tartrate. It’s the hydrogen that is important. A hydrogen atom contains a single positively proton and a negatively charged electron. Because it has a negatively charged electron, it can keep protein from bonding with other proteins. So disulfide bonds are less likely to occur. Sugar: Adding the sugar to whipped eggs too soon will interfere with protein denaturalization process (sugar molecules can get in the way as the hydrophilic amino acids bind with water molecules). The sugar and water molecules also bind, adding more stability to the egg whites by keeping the water molecules from being forced out. If the sugar is dumped in or add too fast will not disperse the sugar evenly throughout the egg whites to build a good network of water and sugar molecule bonds. Gradually beat: the meringue is formed when the amino acids unfurl and bind with water molecules. Then air bubbles push in between the proteins and water. As the water molecules are pushed apart by air. You seen how water can be stretched with tension, you can dribble it down your chin or on the counter. But you can only dribble the water so far. The same thing happens as more air bubbles are beat into the egg whites, the water molecules form a film and spread out. Beating the egg whites gradually and increasing the speed makes for tiny uniform air bubbles and reduces the risk of forcing in so much air that it forces the water molecules out. You always ask really good questions @Cahoots!!! Start with pure egg whites. Beat egg whites on low for about 30 [ATTACH type="full"]3089[/ATTACH] frothy but still translucent add cream of tartar. This is about 30 – 40 seconds of beating on #2 on KitchenAid [ATTACH type="full"]3091[/ATTACH] When they are opaque gradually add sugar. This is about 2 min beating #2 on KitchenAid [ATTACH type="full"]3094[/ATTACH] after the sugar has been added gradually increase the speed every minute. This is pure eggs white [ATTACH type="full"]3090[/ATTACH] [ATTACH type="full"]3095[/ATTACH] [/QUOTE]

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