When Less Really IS More
I get more questions about génoise than about any other type of cake. I understand that. Génoise batter can be tricky stuff. Oh not because the technique is difficult to master. The steps are mostly pretty easy. The danger lies in over-whipping.
It took me years of on-again, off-again génoise making to understand that the degree of whipping and the height of the rise only correlate up to a point. Once you pass it, more whipping begets less volume, even a complete and utter failure (fall). Why?
The reason is the size of the bubbles. Lots and lots of whipping creates larger and larger bubbles. When the cake is put into the oven, those bubbles increase in size. The batter around the bubbles stretches and stretches trying accommodate the volume, but eventually the structure becomes so delicate it can’t support the weight of the batter above it. The bubble pops. That leads to a domino-like effect of more and more bubbles popping, and the cake falls.
What to do? Be careful not to whip the eggs and sugar to the point that ribbons begin to fall from the beater (or whip). If that happens (and it will from time to time), just proceed according to instructions. When you get to the form-filling stage, just knock your batter-filled form on the counter a few times. That will pop most of the really big bubbles and allow the batter to bake up to a reasonable volume.
I’ve read that egg whites should be whipped on low-speed to counteract the above problem. Or, more accurately, start at low speed, increase to med-high only when it has already started to foam, stop whipping as soon as it starts to get fluffy. Apparently, a slower speed creates smaller air bubbles. Does that sound reasonable to you?
Hey Chana! There are all sorts of strategies that supposedly encourage the formation of smaller bubbles. Starting on high and finishing low (five minutes on each setting), starting on low finishing high, etc. In my case I use a beater instead of a whip, and set the machine on medium-high for the duration. I think a génoise batter can be successful with any of them. The real key to the process is the attention of the person running the machine.
– Joe
hi joe, the japanese sponge cake (castella/kasutera) relies on this method of beating eggs on low speed for a very looooo…ng time. The result is a very spongy texture (no offence meant; better than normal sponge cakes) without any addition of fat . The secret lies, as i came to know, after a few failures, in the beating of the egg and the temperature. It felt like archimedis’ “eureka moment” when i got a perfectly spongy sponge cake.
Yes, génoise is almost identical. Warm yolks, steady beating. But you’re right about the exhilaration of getting it right the first time. BOOYAH! It’s an exciting moment!
Revealing post as always Joe! Most genoise recipes don’t emphasise this enough though – not to overbeat the batter. I have a few questions:
1. What do you think is the best way of incorporating the flour? I found that using a whisk resulted in less air loss than using a spatula. Rose Levy Beranbaum suggests using a skimmer slotter but so much flour pocket collected around the holes – disastrous! Some Asian recipes also call for incorporating the flour very quickly by using the electric whisk on low setting. Since this is not recommended in the west I wonder if it would work?
2. Many recipes call for folding in some of the egg mixture to the butter/oil before rather than adding the fat directing to the egg foam. Should this mixture be added to the fat before or after folding in the flour?
Hi Henry! Yes, I’ve thought about that step in the process as well. Unless you’re extremely careful about sprinkling the flour evenly, you do tend to get flour packets in the génoise, which are not fun. I think a whisk is a good idea, and I’ll try it next time. As for the butter/foam mixture, I add it before the flour.
– Joe