Hello Everyone!
I’m starting off the New Year by addressing some of the problems that members experience. An often asked question in Q&A section of our site especially when scaling a recipe up or down, is ‘How long do I bake this cake for and what temperature do I bake at?’
The simple answer is that no one can give an answer any closer than 15 minutes either way of the given time in a recipe. The temperature you bake at may need to be higher or lower than in the given recipe. The only way to find out is to bake it and see. Experience is everything!
Recently, my hubby attended a weekend bread making course that I bought him for his birthday. We are both keen bakers and take an interest in one another’s hobbies. He is the bread man and I am the cake lady! As luck would have it, on the course he met a fellow scientist who works as a conservator and furnace engineer. Meeting this chap gave him the ideal opportunity to discuss on a technical level, this frequently asked question with someone other than myself. I have answered this question on the site many times and it was nice to have my answers validated by an expert. After discussing the thermodynamics of ovens and batters (all the ins and outs), he concluded: ‘In trying to advise on baking times you are on a hiding to nothing.’
Why is this? There are so many variables to consider when trying to work out how long to bake for and at what temperature.
Ovens
The same oven will give different results in different circumstances. Baking times and temperatures will vary within your own oven, depending how you use it. Even moving it to a different place in the kitchen can make a change. You have choices in how you use your oven. Do you bake with fan or non-fan, do you heat from below or above or add baking stones to your oven? Other factors are external insulation and ventilation in your kitchen. From my own experience, if hubby opens the back door of my house I get into a rant because I know that the draft created will significantly affect the rise of my cakes. Oven characteristics will change with age and condition, especially the efficiency and temperature control so it is advisable to buy an oven thermometer to help gauge the calibration.
Batter
The quantity of batter, depth of batter, amount of rise all have an influence on times and temperature. But relating quantity of batter to timing is not straightforward. For example, if you are baking a sheet cake and just want to double the size of the sheet you may need to change little because the tin is shallow and the temperature is cooking the batter evenly all the way across. However if you are changing a recipe from say an 8 inch square deep cake to a 12 inch square deep cake, you would need to lower the temperature and at the same time increase the baking time substantially. There is a much bigger volume of batter and it is more difficult for the heat to penetrate to the centre. When baking at a higher temperature the outside of the cake will overcook before the centre has had a chance to set. The volume of batter in the 12 inch square is twice as much as the volume in the 8 inch square, but you would not necessarily bake the cake for twice as long. You would need to work out these changes from experimenting and from your own experience. Each time a new recipe is tried out it is important to baby sit it and take notes on how it bakes.
Baking more than one cake at a time will also impact on baking times, unless your oven is designed for bulk baking. When baking more than one cake you must be aware of any hot spots or cold spots in your oven. Even large commercial ovens can give uneven bakes.
Baking Pans
The type of material, the size and the shape of the pan you are using is critical in determining baking times. Different metals conduct heat in different ways. A pan made of aluminium will conduct heat more efficiently than one of steel and will bake batter more quickly. Dark pans absorb heat and light coloured pans reflect heat. Ceramics and glass take longer to come up to temperature but will hold heat longer than metal pans.
Climate and Weather
Baking at high altitudes has its own unique challenges. www.highaltitudebaking.com. The higher you go the lower the temperature water boils at. Above 3,500ft the temperature at which water boils is significantly lower, so it is harder for cake batter to set. Water evaporates more readily meaning your batter will dry out more quickly. Examples like Mexico City at 7,300ft have developed their own successful way to bake bread and cakes. Recipes have to be adapted in such places.
Down nearer sea level, changes in the weather can affect your bakes, as do the changing seasons. Humidity affects the time and temperature needed to bake and may affect the crumb. The climate where you live can also have an effect on baking time and temperature for any given recipe. Whether you live in Stockholm in winter, Singapore in the rain or in the hot desert sands of Khartoum baking will be affected by local conditions.
How to test when a cake has baked
Wheat starch begins to gelatinize at 50-60?C. The process continues until the internal temperature reaches anywhere between 80 and 95?C, depending on the recipe. Baking is complete once starch gel forms at the centre of the bake. Sugar increases the temperature at which starch gels. Recipes with a high concentration of sugar will take longer to set. Testing with a wooden skewer will give some indication how far a bake has progressed, but only test once the batter has risen sufficiently to set all but the centre of the cake.
To really understand the complexities of baking one would need to have an extensive knowledge of food science or many years of hands on baking. Experience, no matter how little, is another step forward to better baking. I hope some of the information here helps. However, this blog is only the crust on your cake, digging deeper will pay bigger dividends!
Happy baking, decorating and learning folks!
Best wishes
madeitwithlove x
