If I want to include the process of tangzhong in a sweet bread, do I simply take a portion of its flour and water content and heat that up? Or do I have to recalculate the entire recipe's flour to water content in order to get precise measurements? Is there an easier way to do this?
Here's the recipe I use:
1000g all purpose flour
150g evaporated milk
180g white sugar
20g instant yeast
200g water
3 large eggs
160g butter
5g salt
TIA for any help.
The problem with these recipes for Asian style sweet breads is the hydration is too low. Tangzhong ratio is 1:5 flour to liquid.
When converting to tangzhong, you increase the hydration in the recipe by 10% to 12% depending on the type of flour. You really have to experiment to find how much
This recipe only has 35% hydration. You use 5% - 10% of the flour in the recipe.
If you increase the hydration by 12% it would be 392 mL liquid total (evaporated milk and water).
tangzhong ratio 1:5:
5% of the flour is 50g (.05 ÷ 1000 = 50)
5 x 50g = 250ml
total increased liquid is 392 ml
392 - 250 = 142ml
Remaining flour after 50g used for tangzhong is 950g:
142 mL liquid is not enough for 950g flour as that is only 14.9% hydration.
The liquid in the tangzhong will not provide hydration directly into the flour in a traditional way. Tangzhong works in recipes with the traditional 60% - 65% hydration (adjusted up by 10% - 12% for tangzhong)
This also is probably not the best recipe to use because of the evaporated milk. Canned milk tastes strange and evaporated milk has 60% of the water removed, yet a much higher fat and lactose content than fresh milk because it is concentrated (evaporated milk contains 6.6% fat and 10% lactose vs fresh milk 3.3% fat and 4.5% lactose).
Plus the lactose in evaporated milk is already caramelized due to the evaporation process. The high fat and lactose content of milk adversely effect rise and browning in baked goods.
That said, how to convert a recipe to tangzhong
Use the flour and liquid in the recipe
Calculate the total hydration. This recipe has water and evaporated milk. Add them then divide them into the weight of the flour for the total hydration percentage.
Increase the total hydration by about 10% - 12%. You have to experiment to find out the exact amount that you need to increase the hydration. Make the tangzhong according to the ratio, then add the remainder of the liquid into the recipe.
Tangzhong is 1:5 ratio flour to liquid
Use 5% - 10% of the flour and increased liquid from the recipe. The typical American laziness has them using the microwave. I can’t understand why they can’t be bothered with a sauce pan and spatula and couple of minutes cooking on the stove top. The microwave leads to overcooking. And once you over cook the flour it’s no good. So I recommend you skip the lazy American microwave method, and cook the tangzhong on the stovetop.
Heat the flour and water on the over medium high heat on stove top stirring constantly. I prefer to use a heat proof spatula. When the mixture begins to thicken slightly and the movement of the Spatula through The mixture leaves visible lines with each pass, immediately remove it from the heat transfer it to a clean bowl. Cover the surface with plastic wrap and leave it to cool to room temperature.