Banana bread#
No yeast. No kneading. No proof.
One reaction, and it starts when the batter is wet#
NaHCO₃ + H⁺ → Na⁺ + H₂O + CO₂
1 g of soda → 0.52 g of carbon dioxide → about 290 mL in the bowl, 360 mL once the crumb nears 100 °C.
Most of it is over in two minutes. Mix, fill, bake.
Soda needs an acid. Powder brings one.#
| Raising agent | Starting ratio | Condition |
|---|---|---|
| Baking powder | 1 tsp per 120 g flour | needs only liquid |
| Bicarbonate of soda | ¼ tsp per 120 g flour | needs acid in the batter |
Buttermilk, yoghurt, brown sugar, natural cocoa, ripe fruit. Not Dutched cocoa — it has been alkalised.
The soda figure scales with the acid, not with the flour.
Lumps are correct#
Twelve folds. Stop when the last streak of dry flour goes.
Beat it smooth and you build gluten#
- close, rubbery crumb that resisted the gas
- long vertical tunnels where the gas channelled instead of spreading
- plain flour at 9%, with fat and sugar keeping the strands short
Rye had no gluten to give you. This batter has plenty, and you leave it alone.
Too much soda, three symptoms#
- taste — soapy, metallic, bitter, from leftover sodium carbonate
- colour — darker than the bake time warrants; alkali speeds Maillard
- shape — domes, cracks wide, then sinks; all the gas came before the structure set
Black-spotted, or it does not work#
Ripening is the banana’s own amylase at work: 20% starch and 2% sugar green, the reverse when the skin blackens. Pectin breaks down so it mashes. pH falls to about 4.8.
An hour in a 150 °C oven blackens the skin and kills the enzymes. Soft, bland, starchy, useless.
175 °C for 55 minutes#
Deep tin, half water. At 200 °C the crust is dark at twenty minutes and the centre is still batter.
Skewer with moist crumbs, 96 °C inside. The crack down the top is the crust setting before the middle stops rising — leave it.
It is also the one component of a bake-off 3 showpiece you can mix and bake inside the hour.