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Mantou are plain wheat buns that are steamed, not baked. In the old-dough method a piece of sour dough from the last batch, laomian, leavens the new dough. The sourness is then cancelled by kneading in an alkali, now sodium carbonate, before the buns are shaped, proofed and steamed white and smooth. Made in 5 steps over 8.4 h. The longest step, mix new dough with laomian and let it rise, takes 8 h (Li H 2024) and runs at 30 °C (Li H 2024). Fructilactobacillus sanfranciscensis, dominant in type I steamed-bread sourdoughs and Saccharomyces cerevisiae and Candida humilis do most of the fermenting.
Amounts from a sourceA laboratory recipe built on the starter makers' own instructions, from a study of starters from eight northern Chinese cities; it makes several 60 g buns.
Traditional starter · Laomian or another northern traditional starter[tang2023]
0.45 g
Alkali (food-grade sodium carbonate) · Dissolved with the starter in the water in this method[tang2023]
Starter
backslop (laomian, a piece of the last sour dough)
Total time across the recorded steps: 8.4 h
Start
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What changes:A piece of sour, well-risen dough is kept back from the last batch
Step 1 of 5
Keep a piece of old dough (laomian)
Time
Not documented
Temperature
Not documented
Salt
None given
Acidity
pH 4
Reported
Which microbes the steps name, step by step
Yeasts
Lactic acid bacteria
Laomian is the part of a well-soured, well-risen dough kept back for the next batch. Frozen at −20 °C for six months it lost almost all its leavening power. Output: laomian, the starter for the next batch.
Flavour
sour
Texture
Not documented
Colour
Not documented
Microbes at work in this step
yeasts and lactic bacteria dominate the old dough
Method
Measured measured in a studySet fixed by a specification or tested recipeReported one source reports itTypical a general value, not sourced for this fermentUnconfirmed not yet checked against a source
What makes this one different
Sourdough bread is baked and stays sour. Mantou dough is soured by the same kind of starter but then neutralised with alkali, and the buns are steamed, so they stay white and mild.
Leavening
A piece of the last sour dough, not commercial yeast
Alkali
Sodium carbonate cancels the acid; doughs with alkali measured pH 4.47–6.22, against 4.16–5.44 without
Jiaozi-leavened mantouLeavened with jiaozi, a dried starter made from Chinese daqu, maize flour and melon or rice wine; its initial pH is usually above 5, against about 4 for laomian.
BaoziThe same kind of leavened dough, filled.
HuajuanThe dough rolled and twisted into flower-shaped buns.
Safety
Use only food-grade sodium carbonate, in small amounts. The tested dose was 0.45 g per 185 g of flour.
[yan2019] Yan B. et al. 2019, Microbial diversity in traditional type I sourdough and jiaozi and its influence on volatiles in Chinese steamed bread, LWT 101:764–773, doi:10.1016/j.lwt.2018.12.004 (abstract)paper