The ice age
Ice-creams and sorbets figure on every dessert menu, but not often in the splendid way they once did. In the classic era, ice-creams were a luxury, served as coupés and sundaes, or made into statuesque gâteaux, vacherins and bombes.
When nouvelle cuisine was at its height, sorbets popped up between courses and chefs composed savoury versions from herbs, cucumber and tomato. It was a point of honour for a pâtissier to come up with an "original" flavour, right down to the Chanel No 5 sorbet which was served by one pretentious eaterie.
Fashion nowadays dictates that the ice-cream is one element in a composite pudding. It has to be distinctive, generally less sweet than used to be acceptable and freshly made - not something which has languished for weeks in the freezer.
At Belgravia restaurant Zafferano, head chef Giorgio Locatelli epitomises the current emphasis on intense flavour. He drizzles 60-year-old balsamic vinegar over strawberries; crushes sweet and bitter almonds for an orzata granita; serves rhubarb on an amaretto tartlet with frozen yogurt; accompanies seadas - fried lozenges of lard pastry filled with Pecorino - with vanilla ice-cream. This is modern Italian cookery at its best: stylish, unfussy and imaginative.
The Different Classes Of Ice-Cream And Sorbet
Ice-cream/glacé/gelato
In restaurants that make their own, these ices are made from crème anglaise - a starchless custard base of eggs, milk and sugar.
Crème glacée
Ice-cream enriched with double or whipping cream (30-50%), but some crèmes glacées omit eggs.
Parfait
One litre of boiling sugar syrup (soft ball) is whisked in to 570g egg yolks and the mixture is beaten until cool. One litre of whipped cream is folded into the egg mixture which is then frozen without turbining.
Soufflé glacé
Fruit purée is folded into an Italian cooked meringue. Whipped cream is added and the mixture frozen in soufflé dishes with a collar.
Appareil à bombe
Very similar to a parfait mixture, used to line "bombes". These frozen desserts are not in fashion at the moment in restaurants, but hundreds of recipes exist, dating back to the 19th century.
Sorbet
Professional ice-cream makers tend to divide sorbets into three groups: sweet fruit, acid fruit, and wine/alcohol. Balancing the quantity of sugar or syrup to fruit or alcohol needs working out on an individual basis. Alcohol lowers the freezing point and sorbets containing it will require diluting (eg, Sauternes sorbet: 75cl wine, 75cl water boiled with 220g sugar, 220g glucose syrup, 1tsp lemon juice).
Granita
Water-ice frozen in a tray and forked up to produce crystals, generally less sweet than sorbets and very refreshing.
Spoom
Sorbets which have been extended by a quantity of Italian meringue. These have fallen from favour because most chefs prefer a more concentrated flavour in fruit sorbets, but they have a unique, light texture.
Fruits givres
Citrus fruit sorbets which are piped back into the skins of oranges, lemons, etc.
Ice-Cream: Technical Jargonand Mistakes
Overrun
This refers to the volume of air which can be incorporated into an ice-cream. More than 100% is quite normal for many commercial brands and soft-scoop machines, but hand-crafted ice-creams will normally increase from 40%-50%. Sorbets will expand by about 10% only.
Mistakes
Granular ice-cream - custard overcooked: too much dry matter causing crystallization of lactose.
Lumps/uneven texture - poor beating (machine design fault): the paddle should be flush against the sides.
Large ice crystals - freezing too slowly or badly designed paddle. A similar fault, "sandiness", is caused by smaller ice crystals.
Hard ice-cream - prolonged storage; ice-cream served at too low a temperature.
Tallowy ice-cream - too much fat (cream).
Glucose/Stabilisers
Many professionals add some glucose and/or stabiliser. Glucose is more useful for sorbets because it makes them smoother and helps to fix their colour. Stabilisers are of benefit only if the ice-cream is not to be eaten straightaway. They retard crystallization, which continues to take place during storage, and they can improve the body and texture of citrus sorbets.
Pasteurisation
Pasteurisation takes place automatically during the heating of the custard. The mixture should remain at 70ºC for 30 seconds, but should be heated to about 85ºC before it becomes the correct consistency.
Maturation
Many ice-cream makers claim that the basic mixture's flavour develops if the custard is allowed to mature for several hours before freezing.
Homogenisation
This is an optional extra but a custard which has been blended in a processor or by hand is marginally smoother because of the size of the fat globules.
Turbining
The faster an ice-cream freezes, the smaller are the ice crystals and the better the texture.
Hardening
Turbining freezes only a proportion of the liquid in a mixture. During storage the remaining water migrates to the surface of the ice crystals and the mixture hardens. With prolonged storage more and more of the available water freezes. Even a well-made ice cream loses its finesse. Ideally an ice cream should be eaten within 24 hours.