Vol. XXVI · Doughs of the World Plate 1 of 10烫面, 冷水面, 温水面, 半烫面, hot-water dough, cold-water dough, dumpling dough, 蒸饺, 锅贴, 葱油饼, gluten, gelatinisation, elastic, soft doughMT

Hot-Water and Cold-Water Doughs.

The same flour makes a springy wrapper for boiled 饺子 with cold water and a soft, pleating dough for steamed 蒸饺 with boiling water. The kettle is the recipe.

Chinese wheat doughs are classified by the temperature of the water (面性). Cold-water dough (冷水面), flour and water at room temperature, develops full gluten (VI.10): elastic, chewy, smooth, slightly translucent when cooked — for boiled 饺子 and 馄饨 wrappers, hand-cut and pulled noodles (XXVI.4). Hot-water dough (烫面), made by pouring boiling water onto the flour and stirring, is different: the heat gelatinises part of the starch (VII.1), which soaks up water and becomes a soft paste, and it denatures part of the gluten proteins, so they cannot form a strong network. The dough is soft, plastic and only slightly elastic; it rolls thin without springing back and keeps its shape when pleated, cooks tender and a little sticky — for steamed dumplings (蒸饺, 烧卖), pan-fried 锅贴 and 葱油饼.

Between them are warm-water dough (温水面, at about 60–70 °C) and half-scalded dough (半烫面), in which part of the flour is scalded with boiling water and the rest mixed with cold water, giving some of each texture. The mixing temperature is a heat balance: boiling water poured on flour at room temperature does not stay at 100 °C, but settles somewhere in the sixties — enough to gelatinise wheat starch, which begins near 55–60 °C. The workshop scalds the flour.

Below: the temperature of a dough mixed from 100 g of flour at 20 °C and 50 g of water, the share of it boiling and the rest cold (exact heat balance), the share of the starch gelatinised (course wheat-starch kinetics) and a teaching index of the elasticity left, from cold-water to hot-water dough.

What you will learn
Workshop
Heat balance, exact: T = (m_w c_w T_w + m_f c_f T_f) ÷ (m_w c_w + m_f c_f), water 4.19 kJ/kg·K, flour about 1.6 kJ/kg·K, the boiling share at 100 °C and the rest at 20 °C. Gelatinised: the boiling share of the water scalds a matching share of the flour, which reaches the all-boiling temperature; the course wheat-starch kinetics over two minutes there, capped at 60 % because so little water cannot swell all the starch (teaching). Elasticity (teaching): 1 − gelatinised share.

Choose the water by the cooking method

With all the water boiling, the heat balance puts the dough at about 65 °C as it is stirred — the water cools sharply on the cold flour, but the scalded part of the flour still reaches the gelatinisation range, and the model gelatinises about 0.60 of the starch; with half the water boiling, about 0.30. That is why recipes for 烫面 insist the water be truly boiling and poured on quickly while stirring, and why hot-water dough must then cool, uncovered or spread out, before kneading: trapped steam would make it wet and sticky.

Choosing: boiled dumplings and noodles — 冷水面, about 50 % water, kneaded smooth, rested 30 minutes (醒面, XXIV.4). Steamed dumplings, 烧卖 and 葱油饼 — 烫面, about 55–60 % water, boiling water stirred in, cooled, kneaded briefly. Pan-fried 锅贴 and 馅饼 — 半烫面, half the water boiling, half cold, for a soft wrapper that still holds a crisp base. Warm-water dough suits 花卷 and some 包子 (XXVI.3). Salt in a cold-water dough tightens the gluten for noodles; a little oil softens 烫面.

At the stove

Make two small doughs from the same flour, one with cold water and one with boiling water. Rest both, roll them thin, and compare how much they spring back and how they feel.

面性 — the "nature" of a dough by its water — is one of the first lessons in Chinese pastry (白案) training; a 白案 chef is judged by how well each dough suits its dish, as a 红案 chef is by fire and knife.

Terms

冷水面
Cold-water dough: full gluten, elastic and chewy.
烫面
Hot-water dough: partly gelatinised, soft and plastic.
半烫面
Half-scalded dough: some of each.
面性
The character of a dough, set by its water temperature.
冷水面 keeps gluten: elastic, chewy — boiled dumplings, noodles. 烫面 gelatinises starch and weakens gluten: soft, plastic — steamed dumplings, pancakes. 半烫面 sits between. Boiling water on cold flour settles near 65 °C.

Sources

  1. A teaching value chosen for the course: the right order of magnitude and shape, not a measurement of a particular food.
  2. Starch gelatinisation ranges measured by DSC: wheat about 52–64 °C, potato 58–66 °C, maize 62–72 °C, rice 68–78 °C, tapioca 59–70 °C (S. Damodaran and K. L. Parkin (eds.), Fennema's Food Chemistry, 5th ed., 2017, ch. 3). The course uses the midpoints.