Making a poached egg can get pretty tricky even for the pros. Once you release an egg into hot water, there's simply no telling if the egg will dismantle or hold its shape. Of course, choosing eggs with the right temperature and moderating the water temperature helps the recipe. But then there are some common mistakes which are hard to avoid, such as overcrowding the pot or stirring the pot too often.
A good trick is to make sure your water is at a low simmer (not a boil) when you start poaching and setting up a timer so you don't overcook them. But another great hack is to use vinegar! If you think using vinegar in your eggs will make them taste strongly acidic like table vinegar does, you're wrong. Adding one tablespoon of a light-coloured vinegar does not flavour the egg but it does help to keep the egg white together. Adding a splash of vinegar to the water basically sets the whites faster, so you have fewer wispy bits. And turns out there's a science behind this hack.
Why vinegar?
Vinegar is an inherently acidic material, so if you add a few drops of vinegar into the boiling water that is going to increase the rate of denaturing (the process of protein molecules unravelling from their naturally coiled state. With eggs, this happens most frequently when they're heated or beaten) and it’s going to make that happen faster and help the poached egg hold its shape better. Your best bet is using malt vinegar which is a by-product of ale that is fermented past its drinkable stage.
Malt vinegar usually has a mildly nutty, toasted flavour from the malted barley. When added to eggs or something savoury it offers some sweet undertones which make the poached egg more flavourful. Fill a large pan with water, add a splash of malt vinegar and bring it to the boil before you add in your egg.
In case you don’t have access to malt vinegar, another method also works. Use a fine mesh sieve to make your poached egg. Remember that most wispies in the poached egg are made by the liquidy white, which is harder to temper. Add the egg to a fine mesh sieve which removes the thinner, more liquid white, leaving behind only the firmer white which will envelop the yolk. Poaching at a 180°F (82°C) sub-simmer will guarantee fewer disturbances in the water and a more tender finish