依然是个谜的戚风蛋糕凹底

 今天做了一个海绵戚风蛋糕，用的配方是萨姐的，但是把面粉增加了一些，否则蛋糊太稀

我已经很注意以下几点了，这几点据说能避免蛋糕凹底

1. 蛋白里不加白醋

2. 蛋白要打发到干性发泡状态，也就是盆里的蛋白质霜是直立尖角状态，打蛋头上的蛋白霜也是直立尖角

3. 烤盆放在烤箱中下层

今天用五个鸡蛋做的巧克力戚风蛋糕，在烤箱里膨胀的高度刚好到烤盘的高度，算是长得最高的一次，表面开裂也是细微。外观看很完美。但没想到的是，倒扣晾凉后，底部脱模非常容易，当下就觉得一定是底部凹底。一翻开一看，果不其然

搜到有人在Quora询问戚风凹底的问题。和我的情况一模一样

https://www.quora.com/Why-is-my-chiffon-cake-pulling-away-from-the-bottom-of-my-pan-I-havent-greased-it-The-sides-stick-firmly-enough-so-when-I-invert-it-it-doesnt-fall-out-But-because-the-bottom-pulls-away-it-causes-the-middle-of-the

Why is my chiffon cake pulling away from the bottom of my pan? I haven't greased it. The sides stick firmly enough, so when I invert it, it doesn't fall out. But because the bottom pulls away, it causes the middle of the cake to become dense.

有一个人的回答让我很感兴趣。他提到烤好后不要立刻拿出来，而是jai fai

Now this I think was the game changer for me. After the baking time, I don't take out the pans straight away from the oven to cool. So I invert them in a cookie sheet, put them back to the oven with the oven door open for few minutes then take them out a bit then finally take them out. The whole process should be less than 10mins coz otherwise it will continue baking and we don't want a super overbaked chiffon. I feel that maybe my cake was shrinking at the bottom before because of the sudden change of temperature. As we know, chiffon is very delicate and sensitive. So when taking it out of the oven, try to make the temperature change as gradual as possible. But make sure you invert it straight away after baking.