Bake Like a Chemist

The Great British Bake Off is back on our screens to cheer and amaze us with wacky creations – hurray!!

Baking was the biggest growth activity under lockdown – you’ll remember the empty shelves where the flour had been snapped up.

Our U3A Science group is also back up and running – hurray again!!

The first talk, from the highly entertaining chemist, Steve Wilson (he does talks on cruise ships), delved into the science of baking.

Chemists make great bakers being expert and weighting, measuring, mixing and heating things. We’ve seen something similar with the precision of engineer Bake Off competitor Guiseppe.

So here is a cakey mix of Steve’s fascinating insights and my thoughts on health.

It starts with beating sugar and butter until pale and fluffy. The sugar keeps the specs of butter apart. Any blobs of butter left will melt in the oven, leaving holes in your cake.

Health-wise sugar is bad. You can retrain your palate in only a couple of weeks to prefer less sweetness so you can cut down the amount of sugar in the recipe. You can also use substitutes like xylitol (a sugar alcohol).

Fat is an essential ingredient – butter works well, gives great flavour, is stable when cooked and is healthy.

Vegetable oil and margarine are unhealthy and damaged by heat so it’s better to avoid them altogether.

Coconut oil is very good and gives a different flavour and texture.

Flour brings gluten which provides elasticity. Anyone trying gluten-free baking will miss how pliable bread and pastry dough are in particular.

Flour is soon-to-be-sugar. It’s starchy carbohydrate which is a chain of hundreds of sugars holding hands. Your enzymes quickly break starches down into simple sugars which hit your blood stream and stimulate insulin production. The insulin takes excess sugar out of your blood and stores it as fat. This is the Carbohydrate/Insulin model of weight gain.

Baking powder is a raising agent found in self-raising flour or added separately. It contains acidic cream of tartar and alkaline bicarbonate of soda which react when wetted to make bubbles of CO2 and cause your baking to rise and be light and fluffy.

Eggs are high in protein which has many hydrogen bonds and these give strength to the bubbles. Eggs are also a raising agent. If you use coconut flour, it’s very dry and it helps to add an egg for each ounce (28g).

Dr Phil Hammond calls bought cakes, chemical cake. As Steve pointed out, it’s all chemistry! But Dr Phil is right, bought cakes have undesirable ingredients that your body doesn’t appreciate. Also they’re usually made with unhealthy vegetable oil so baking your own is preferable.

Portion size does matter – cake is something to be enjoyed in small amounts. I think I remember reading that Paul Hollywood put on a stone and a half during the last series of Bake Off! Huge slabs of cake have become normalised in shops over the years (I wrote about muffins some years ago) but you can of course ask for extra forks and share between friends.

Top tip: Love cake? Make like a chemist and get baking.