Best Loaf Tin for Sourdough: What Actually Matters

Sourdough is harder on a loaf tin than anything else you will bake in one.

A cake batter goes into a cold tin, sits there for fifty minutes and comes out. A tin sourdough is shaped, dropped in, covered, and left in the fridge overnight — eight to fourteen hours of wet, acidic dough pressed against the metal before the oven is switched on. Then it bakes hotter and longer than a cake.

Most tins sold as non-stick loaf tins have never been asked to do that. Which is why the search that brings people here usually starts the morning after a bake, working a palette knife down the side of a welded loaf and deciding whether to lose the crust or the base.

Why a tin at all, when everyone bakes in a Dutch oven?

Worth answering, because it is the first objection. A cast-iron pot with a lid gives the dark, blistered boule sourdough is famous for. A tin does not, and no tin will. What it gives you instead is a loaf you can slice for sandwiches and fit in a toaster, and it forgives a slack dough that would spread into a puddle on a baking sheet. For anyone baking sourdough as the household bread rather than a weekend showpiece, the tin is the more useful tool.

The metal: gauge matters more here than anywhere else

Thin pressed aluminium warps. It heats unevenly, one part of the sheet expands faster than the rest, and the tin buckles to relieve the stress. That is the bang you hear from the oven ten minutes in. The consequences are worse for sourdough than for a cake, because the bake is hotter and longer, so a tin that flexes flexes more. A buckled base gives a pale, damp bottom crust on one side and an over-coloured one on the other, and once the base is domed it never sits flat again.

The slower damage matters more. A non-stick coating is bonded to the metal underneath it, and every flex works at that bond. This is why so many bakers tell the same story — a tin that released beautifully for a year, then began to grip, then began to shed. The coating did not wear out. The metal moved. We set out the mechanism in our guide to carbon steel versus aluminium bakeware.

Heavy-gauge carbon steel solves both problems at once. It stays flat through a 220°C bake, and because the steel does not flex, the coating stays put. Pick a tin up before you buy it if you can: a good one feels solid, a bad one gives under your thumb.

Glass and ceramic conduct heat slowly, so longer bakes and paler sides. Silicone is worse again — it browns poorly and bows outwards when full, so a 900g dough gives you a loaf with a waist.

The coating, and the question nobody answers

Ask a baking forum whether sourdough's acidity damages a tin and you will get confident answers in both directions with no evidence behind either. Here is the honest position.

Sourdough is mildly acidic, roughly the pH of orange juice. That is not going to eat through steel during a bake. What it can do, over months of long fridge proofs, is find the places where protection has already failed: a scratch through the coating, a bare seam, a rolled edge where water sits after washing. Bare and tinned steel tins are the ones to watch, having nothing between dough and metal — which is why those are traditionally wiped out rather than washed.

A coating properly bonded to the steel, and unscratched, is not troubled by dough acidity in normal home use. What we have seen fail is the sequence that starts with a metal knife. Ours is a double-layer non-stick made without PTFE or PFOA, and it takes a palette knife down the side without giving up — which matters, because sooner or later you will run something down the side of a stuck loaf.

What size, and how much dough goes in it

This is where most guides quietly fail. They give one dough weight for one pan and leave you to guess.

Dough type moves the number more than tin size does. A wholemeal dough and a white sandwich dough of the same weight fill a tin quite differently, and bakers using the same tin report figures half a kilo apart. So work your own out once and stop thinking about it:

Before you get the jug out: a 1lb tin takes somewhere around 450 to 550g of dough, a 2lb tin around 800 to 900g. The 2lb loaf tin is the size most people want for sourdough, because it gives the standard family sandwich loaf of eight to ten slices. A 1lb non-stick loaf tin suits one or two people, or a test bake of an unfamiliar flour.

Fill level matters as much as weight. Shape the dough, drop it in seam-side down, and prove until it has risen by roughly half — sourdough does not want the full doubling a yeasted dough gets — finishing level with the top of the tin or just proud of it. The poke test still works down in a tin: press a floured finger into the shoulder, and if the dent fills back over about a minute it is ready.

The tins

All three carry the same 10-year guarantee, which covers the two ways a loaf tin actually dies: the metal warping and the coating peeling or blistering. Most tins at this price come with a year, if anything, and the quiet expectation that you will be back. Guaranteeing one for a decade only makes commercial sense if it lasts one. The rest of the range is on the loaf tins page, and our best loaf tin UK guide covers the same ground for bread generally.

Getting the loaf out

Two things stop sourdough sticking, and neither is more grease.

The first is fat that behaves at bread temperatures. Olive oil goes tacky and varnish-like well before a loaf is baked, which is why bakers who switch to block butter — not the spreadable kind — so often report the problem disappearing. Butter, then a dusting of rice flour over the top, rice flour being the one with no gluten to hydrate and turn to paste.

The second is heat underneath. If the sides release and the base stays welded, that is not a greasing failure. It is an underbaked bottom, and the answer is a lower shelf, a preheated tray under the tin, or five more minutes. Bread that will not come out will often release itself if you put it back in.

If it is stuck right now: leave it two minutes so the loaf contracts as it cools, bang the tin flat on the worktop, and only then reach for a plastic scraper — never a serrated knife. The circular version of this is real, because a stuck loaf leads to a metal knife, the knife scratches the coating, and the next loaf sticks worse. Our guide to stopping bread sticking to the tin works through the sequence, and lining a loaf tin properly covers the parchment method for doughs that need it.

Afterwards, wash by hand and dry the tin straight away rather than leaving it on the rack. A tin that goes away damp is the one that develops a rusty seam, and the seam is where the acid finds a way in. The care and use guide has the full routine.

Why the crust is paler than you expected

A lidded pot traps the loaf's own steam for the first twenty minutes, which keeps the surface soft enough to expand and gelatinises the starch on the outside. That is what gives gloss and colour. An open tin in an open oven has none of it.

Three responses, in order of how much they help. Put a metal tray on the shelf below and throw a handful of ice cubes into it as the loaf goes in. Invert a second tin of the same size over the top for the first twenty minutes. Or accept it, because a softer, thinner crust is what a sandwich loaf wants, and a fair number of people complaining about it are describing a feature.

What does not work is turning the oven up. A tin loaf wants around 220°C for twenty minutes and 200°C for the remaining twenty-five to thirty, fan ovens twenty degrees lower. Past that the top colours before the middle is done; if it browns too fast, tent it with foil. Bread is done at 95 to 98°C in the middle.

The short version

Heavy-gauge carbon steel, coating bonded straight to the metal, 2lb size unless you know you want the small one. Work your own dough weight out once with a jug of water. Block butter and rice flour, not olive oil. And if the base sticks while the sides release, bake it longer rather than greasing it harder.

The tin is not usually why a sourdough goes wrong. It is just the only part of the process you can fix by buying it once.