A new ice age

InÁ‚ the past, the most critical ingredient of ice-creams and sorbets was sugar. It determined how hard the frozen liquid base would be Á¢Â€Â" too little meant a hard, dense ice; too much equated with a soft or sticky mixture.

Most standard recipes contain between 25% and 35% sugar (or sugar and glucose). A recipe for a typical, top-of-the-range ice-cream base might read Á¢Â€Âœfive egg yolks, 225g sugar, 25g glucose, 600ml whole milk and 300ml creamÁ¢Â€Â. Sorbets, allowing for differences in the sweetness of various fruits, work around the same sweetness-to-liquid ratios.

Ice-cream machines (sorbetiÁƒÂ¨res) of whatever type perform two functions. They freeze and simultaneously break down ice crystals to create a smooth texture. At the same time, their churning action beats air into creams, adding volume and making the product seem lighter. But the Pacojet rewrites the rules for making ice-cream. Sweetness is no longer an issue, except one of personal taste. Theoretically, it would be possible, even easy, to make a silky-smooth unsweetened turnip sorbet. Claude Bosi, at Hibiscus in Ludlow, prepares one with raw, green apple peelings.

ItÁ¢Â€Â™s a technology that has been around for a decade. Anton Mosimann was probably the first chef in the UK to use this Swiss-made equipment. Only now, though, are British chefs coming to grips with it.

The principle is simple: raw product (liquid, solid or a combination of both) goes in a container to be stored at -20Á‚°C till needed. The machine breaks down the frozen block by shaving off successive microscopically thin layers, then blends the whole batch, or only a part of it, to order automatically. Ice crystals (the liquid phase) and solids combine to form a kind of frozen emulsion, which is ready to scoop or form into quenelles. A portion may take less than a minute to prepare.

Equipment
The Pacojet is an automatic ice-cream and sorbet maker designed for small batches. It has separate cutting blades (stainless steel or gold-coated for heavy-duty chopping), an outer protective container and an anti-splash lid. The chrome steel inner container, for processing, takes only 750ml by volume, though contents can expand to one litre.

To operate it, the chef freezes the chosen product to -20Á‚°C in the container. After removing its lid, he puts this into the outer sleeve. He fits the blade to the anti-splash lid and clicks it into place on the shaft that protrudes from the main body. The outer container then locks into it.

Processing begins at the push of a button. The operator chooses from one to 10 mini-cycles, depending on the amount of product in the container, its consistency or the proportion of product he wishes to blend. A full batch takes about four minutes. Mini-cycles last less than a minute.

During Á¢Â€ÂœPacotisingÁ¢Â€Â the blade turns at about 2,000rpm. Each turn shaves a layer off the top of the product, so that the blade is