Why heat the eggs for a génoise batter?
Reader Carly wants to know why génoise batter calls for gently warmed eggs. Is it a food safety thing? Actually no, Carly, the reason we warm the eggs before whipping is to ensure that they whip up as high as they reasonably can. Cold egg albumen (white) is thicker than warm egg albumen. As such it’s more resistant to the effects of a whip. Bubbles are a factor of the amount of shear force that can be applied to the white and/or yolk. With a thinner liquid you simply get more of them. Consider which a whisk will cut through with greater speed and force: a bowl of water or a bowl of maple syrup. Thin albumen is why bakers prefer warmer, older eggs over colder, fresher eggs since they’re easier to put the hurt on. Make sense?
I think I remember hearing that it’s good in general to bring eggs to room temperature before whipping them, but that cream (and the bowl and beaters) should be cold. I know cream doesn’t have albumin to thin or thicken, so that’s not a factor, but why is it so important that it be cold?
Hey Sandra!
You’re very right on both counts. I like that whipped cream question so I’ll answer it on the blog today!
Cheers,
– Joe