Bread knife

Points, not an edge

A straight blade has to overcome the resistance of the whole surface it meets at once. On a hard crust over a soft crumb that means pushing down hard — and the crumb, being far weaker than the crust, collapses before the crust gives.

A serrated blade meets the crust at a small number of points, each carrying the full force. Those points pierce the crust with very little pressure, and the scalloped edges between them then slice through what is behind.

That is why the technique is different too. A bread knife wants a long sawing stroke and almost no downward pressure; pressing is precisely what squashes the loaf.

What else it is for

• Tomatoes and other thin-skinned fruit, where a slightly blunt straight knife slides off the skin and a serrated one bites straight in.
• Cakes, both slicing and splitting into layers. The sawing action does not compress the crumb.
• Melons, squash and pineapple, where the length and the teeth both help.
• Anything with a hard exterior and a soft interior — a crusty pie, a baked camembert in its box, a large aubergine.
• Citrus for segmenting, where the skin is tough and the flesh delicate.
• Not for chopping. It cannot rock, it is usually blunt-tipped, and it makes a poor job of everything a chef's knife does.

Choosing one

Length

Longer than the widest loaf you cut — 20 to 25cm is standard. A short bread knife needs more strokes and more compression.

Tooth pattern

Pointed teeth cut aggressively and tear soft crumb slightly. Scalloped waves are gentler and better for cakes.

Offset handle

Raises the knuckles above the board. Useful if you slice a lot of bread; unnecessary otherwise.

Flexibility

A stiff blade is easier to control. A flexible one is better for splitting cake layers.

Price

One of the few knives where a cheap one performs nearly as well, because sharpness matters far less.

Using it well

1. Let the knife do the work. Long strokes, almost no downward pressure.
2. Start with the tip and draw back towards you to score the crust, then saw forward.
3. Cut a completely cooled loaf. Warm bread compresses however good the knife is.
4. Turn a round loaf on its side for the first cuts if the crust is very hard.
5. For cake layers, mark all the way round the outside first, then saw inwards.
6. Keep it separate from the sharpening steel and the knife block edge. Serrations chip.

Sharpening and alternatives

• It cannot be sharpened on a steel or a stone in the usual way. The teeth have to be addressed individually.
• A tapered ceramic rod or a small round file works, one scallop at a time, on the bevelled side only.
• Most people replace rather than sharpen, and a serrated blade stays usable for years because the mechanism is less dependent on edge.
• If you have no bread knife, a long thin knife with a sawing motion and no pressure will do, badly.
• A very sharp chef's knife works on soft loaves and fails on anything with a real crust.
• An electric knife cuts bread and cake beautifully and is one appliance too many for most kitchens.

Common questions