Emulsions: A saucy discussion

Ever had Hollandaise sauce with eggs? A vinaigrette dressing with salad? Ever eaten mayonnaise or just milk? You've eaten so many emulsions and you don't even know it! You've consumed tasty dispersed media!

In terms of cooking, an emulsion is often what you get when you manage to mix two liquids that normally don't mix. A common example is fat and water. So how do you mix them? You need some "glue" to get them to mix. That's what an emulsifier does!

Mayonnaise is an emulsion of oil and water, with emulsifiers from egg yolk. Tiny droplets of oil are dispersed in the water. Emulsifiers sit in between them and keep them separated. They stabilise the emulsion. Isn't it interesting how you mix oil and water and you get something thicker, more viscus?

So what about Xanthan Gum? In the culinary world it is used to thicken sauces or to stabilise emulsions. That's why you find it in so many condiments and sauces!

I was pleasantly surprised to find Xanthan Gum in a local store recently! It is often used in gluten-free baking as a gluten substitute. Also, low-fat products (e.g. "light" mayonnaise) have less oil, so Xanthan Gum helps thicken them up.

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