1. Recipe problem: the proportion of oil or water in the recipe is too much, which makes the cake too heavy for its own weight and produces collapse.

2. Batter has become glutenous: The batter has become glutenous due to improper mixing, and the cake shrinks back when it cools.

The solution: use low gluten flour, note: the egg yolk paste should be up and down to mix, not circle mixing.

3. Protein defoaming problem:

Whipping is not in place, or whipping stays in the whipping for a while before beating, or whipping time is too long, the order and timing of adding sugar is not right .... are not easy to reach dry foaming, so the protein foam is not stable, easy to defoam, the air holes are reduced, so that the volume of the cake batter is reduced, the cooked cake body in the cool to retract. After defoaming the egg mixture is easy to settle, baked into the pudding layer, which is also a possible cause of the cake retraction.

Treatment:

a. Egg beaters, egg beaters should be clean, there can be no water and oil, it is best to use stainless steel beaters;

b. Use fresh eggs, preferably after refrigeration, the egg white yolks are separated cleanly, especially the egg white can not be left a trace of the yolks; the addition of sugar and white vinegar to help whipping, stabilize the foam effect.

c. At the beginning of the low speed beat - after the coarse foam start to add 1/3 of the sugar, medium speed whipping, the middle of the 2nd 3rd sugar, continuous beating, do not stay too long in the middle of the beat again, and keep beating until dry foaming.

(dry foaming level test: tilt the bowl, foam are not active, not put down, lift the beaters, see a short sharp corner, the basin also see the sharp corner of the upright not down. (At this time there is a little cotton wool-like foam organization on the edge of the basin, is allowed.)

4. Uneven egg yolk paste problem

Egg yolk paste is not evenly mixed, the fat is not completely emulsified well, or egg yolk paste and egg white paste phase mixing is not even, as well as the aforementioned egg white paste defoaming, all of these conditions will be due to the more than serious components of the composition of the sink, after baking constitute the layer of pudding, incurring the cake fluffy not up.

How to deal with it: control the mixing essentials, light action, speed, but be sure to mix well.