# Temp and time for using half the recipe of cake

I have a recipe which makes cake for 6-8 ppl. I want to bake the same recipe using just the half recipe. It's original temp. Is 180 C using 40 minutes. Now after using just the half recipe what will my temp. And time be.. Please reply

• Are you using the same size pan or a smaller one? Generally you can keep the temp the same and halve the time... and then watch until it's done. Commented May 25, 2015 at 6:12
• Start checking it after 1/2 the time ... but it'll likely take closer to 3/4 of the time, as it doesn't scale linearly when you move things to a smaller pan. (it might be 1/2 the time if you kept it in the same size pan, so it's 1/2 as thick ... but that also tends to lead to overcooking)
– Joe
Commented May 25, 2015 at 11:49
• I found a box cake mix that adds water, oil and eggs. If you use a 13 inch by 9 inch pan you bake 28-33 minutes at 350 F degrees in shiny metal pan or 325 F degrees in glass pan. Two 8 inch round pans 28-33 minutes 350 F or 325 F, two 9 inch pans 24-29 minutes at 350 F degrees or 325 F degrees. Sorry, pls do the math to convert your 180 C to my 325 F and 350 F. I checked my pans and the 13 by 9 was the same depth as the 8 inch but the 9 inch was larger so half would be a flatter dough hence, less cooking time. I would put toothpick or knife to check if dry at the earlier time to see if baked Commented May 26, 2015 at 9:46
• To continue, if you use a pan that is half the size and comes up to the same depth, the cooking time should be the same according to the box mix I found. Remember that shiny metal pans (or non-stick pans) have a higher temperature and glass pans are 25 F degrees lower. Again, sorry that you will have to figure that one out for yourself. Also, do you have any box cake mixes that you can check for yourself at home or call someone who uses them. That could be helpful to you. All this info is based on a pretty simple cake. Good Luck Commented May 26, 2015 at 9:56

As @joe said, it does not scale linearly.

There are various factors that effects cooking time:

Thickness: the heat transfers mainly from the top and bottom for a round on a not too thick to thin dish, so for half a cake with the same thickness the time will stay about the same. Think of a pizza for example, whether it's 5 or 15 inches in diameter the cooking time is nearly exactly the same. For a very thick cake, though (sponge cake for a wedding cake for example), the lateral heat transfer will matter far more.

Chemical reactions: Some chemical reactions (egg coagulation, Maillard, unfolding of proteins etc.) happens at a very specific temp under which they don't happen at all or takes forever. For example the coagulation an egg at ambient temperature will take several years, where it would happen in a few minutes at 65 centigrades. Try browning a toast at 90 c (half of the temp needed), it'll never happens. It takes 180c to start burning bread, anything under will stop the expected result from happening .

Most chemical or physical reactions (water boiling) that gives the expected taste or texture to something you bake happens between 60 to 180 c so do not change the temp when changing the amount in a recipe if the temp indicated is within that range.

If you cook a bigger item a higher temperature it won't have a chance to cook internally before being burnt on the outside, on the opposite, a smaller item with the same shape will be crisp and nice at the same temp.

As for the time needed, only on very compact items, nearly spherical, such as scones, choux pastry, or poultry (think of the time needed to roast a breast of chicken vs a whole chicken vs a turkey) the amount of time will be more closely proportional to the size or weight. You cook the smaller item less longer.

In brief: don't change the temp if it's equal or less than 180c. If your cake is compact (like a banana bread cooked in a tin) drop maybe around a quarter of the time for a halving of the recipe, and maybe a sixth of the time for a thinner cake.