Pantry Lovers Series 5 – Homemade Baking Powder

Oh, baking powder. Sometimes it’s all that stands between you and failure. Such a simple little thing – it’s the fluffiness in your cake, the rise in your biscuit, the levity in your pancake. We can go for years without even seeing it (hello, self-raising flour), but when it fails us, we feel it deeply.

Shall we talk about the first time I met my cookbook publisher? She was driving down to the farm, arriving around morning tea-time, and so, perhaps obviously, I whipped up a batch of Visitor Biscuits (recipe coming soon!), of which I have made one hundred and seventy bazillion batches in my life. Maybe one hundred and eighty. This is the biscuit we have taught for nearly ten years in our From Scratch class and made and sold as part of Buena Vista Farm Bikkies. You’ve probably already made or eaten something very similar. Anyway, I pulled them out of the oven, confident, the timing was perfect …  and they looked like small warty rocks. Nothing delicious about them. Unable to be covered in icing sugar and resurrected in any way. Chook food. (I served cheese and crackers instead.) It was the self-raising flour. It was dead. By that I mean the raising agent in it was inactive. Honestly, when we had a bikkie business I would never have dreamed of using self-raising flour; I always declared I wanted to control the rise, and the salt, and also the aluminium (more on that in a sec), but convenience sometimes wins and so I had a bag in my pantry. My bad.

Okay, first let’s look at what baking powder really is. Your supermarket baking powder is typically bicarbonate of soda (or ‘sodium bicarbonate’, or also commonly called ‘baking soda’) plus cornflour (cornstarch) and cream of tartar. The cornflour is just there to absorb moisture and stop the powder from clumping. Bicarbonate of soda is an alkali agent, and cream of tartar is an acidic by-product of the winemaking process. Baking powder is stable until it comes in contact with liquid, which is when the magic happens, because with liquid, the bicarb’ soda and cream of tartar create carbon dioxide, COOL hey? That is, alkali plus acid plus liquid equals carbon dioxide (or, fluffy scones.)

So, what’s with the aluminium in baking powder? Self-raising flour, if you look at the ingredients, usually contains both ‘raising agents’ and ‘acidity regulators’. Once the first reaction happens, it loses its ability to rise fully again – and delay is fatal to fluff. Aluminium sulphate, however, reacts with the baking soda and cream of tartar when heated, so it’s actually called a second acid, or double acting. Almost all self-raising flour contains aluminium sulphate, which I knew, and bought it anyway, so it served me right when it expired and I produced a dreadful tray of inedible biscuits.

The moral? Avoid aluminium in your diet. Research has found aluminium in amyloid plaque in brains with dementia, so let’s avoid that shall we?
You don’t need double-acting flour. You just need to use fresh baking powder, and not leave whatever it is you’re baking sitting around unnecessarily before it goes in the oven. Buy plain (all-purpose) flour and add your own rise!

One last thing: how do you test if your baking powder is still active? Put half a teaspoon in a cup and pour 60 ml (or ¼  cup) boiling water over it. It should froth. If it doesn’t, you’re going to have a flat cake. Frothing baking powder is the business.

Makes 1 tablespoon / 20 gm
 
Ingredients

1 teaspoon bicarbonate of soda (baking soda)
1 teaspoon cornflour (cornstarch)
2 teaspoons cream of tartar

Or, depending how much you are making, use these proportions:

One-part bicarbonate of soda (baking soda)
One-part cornflour (cornstarch)
Two-parts cream of tartar

Method

Mix together. Store in an airtight container.

Note
This will begin to lose potency after about a month, so only make up what you’ll use in that time. If you’re avoiding corn, substitute arrowroot powder for the cornflour.
If you’re making this on the go and not planning to store it, you can leave out the cornflour and then you proportionally only need 1.5 teaspoons baking powder to 150 g (1 cup) plain (all-purpose) flour.

Self-raising Flour

Make it up fresh and never accidentally make small-warty-rock biscuits.
Makes 150 g (1 cup)

Ingredients
150 g (1 cup) plain (all-purpose) flour
2 teaspoons Baking Powder (recipe above!)

Method
Combine the plain flour with the baking powder. Ideally, sift them together but if you’re like me and have a mental block about sifting, combine briskly with a whisk.

Note
If you’re making your own Baking Powder and it’s freshly made and does not contain cornflour (cornstarch), reduce the amount of baking powder to 1 ½ teaspoons per 150 g (1 cup) plain (all-purpose) flour.

Recipe adapted from Fiona Weir’s book “From Scratch” published by Hardie Grant 2022, photography by Alan Benson