Modern technique, and waste

Two techniques arrived in bars from restaurant kitchens and are now common enough to belong in a book like this. Both are ways of changing a liquid's texture or flavour without changing what's written on the spec.

Alcohol dissolves the flavour compounds in fat. So: melt a fat into a spirit - browned butter, bacon fat, toasted sesame oil, coconut - leave it to sit, then freeze it. The fat solidifies and lifts out, and what's left is a clear spirit tasting of it.

1. 1Melt the fat and stir it through the spirit. About 120 g per 750 ml for something strong like smoked bacon, about 240 g for butter, olive oil or anything mild.
2. 2Leave at room temperature for a few hours, stirring occasionally. Room temperature rather than warm, because heat drives off the top notes of the spirit you're trying to keep.
3. 3Freeze overnight.
4. 4Lift off the solid cap and strain through a coffee filter.

A brown-butter bourbon Old Fashioned is the usual demonstration.

Milk-washing turns a cloudy drink clear while softening its acidity. Pour the finished, acidic cocktail slowly into room-temperature milk - not the other way round - at about five parts drink to one part milk, and the casein proteins curdle; as the curds form they trap the particles, tannins and colour that made the drink cloudy. Strain, and what comes through is clear and noticeably silkier.

The result keeps far better than the drink it came from, which is why it pairs with batching: a clarified batch can be poured for weeks. Directional freezing, the clear-ice trick from the ice chapter, is sometimes used the same way.

A bar juices a case of limes and bins the husks, cuts garnish and bins the offcuts, and pours away what doesn't get drunk. The volume adds up quickly.

• Peels before juice. Peel citrus for oleo saccharum first, then juice the naked fruit. Two ingredients from one lemon.
• Husks after juice. Spent halves still hold oil; they can be dehydrated and ground for a rimming salt.
• Batch to a size that gets drunk. The largest single source of waste is over-preparing.
• Use the whole herb. Mint stems have flavour; they can go into a syrup rather than a bin.

That's the end of the book. The other half of the site is what came out of it.