Types and composition of frozen desserts

By varying quantities of main ingredients, numerous types of frozen dairy desserts can be produced

Ice cream and ice milk. Major components of ice cream are known to be milk fat, nonfat milk solids, sugar, stabilizer, and flavouring. There exist a wide range for producers to vary content of both milk fat and nonfat milk solids, the quantity of one component being increased, thequantity of the other being decreased. Ice cream has the highest fat content, ranging from 10 to 20 percent.

Frozen custard, or French ice cream, is basically the same formula as ice cream except that in finished form it must contain at least 1.4 percent egg yolk2 solids.

Plain ice creams contain colouring and flavouring ingredients (such as vanilla, coffee and maple syrup) no more than 5 percent of their unfrozen volume

Ice milk may be more commonly called "light" or "reduced-fat"4 ice cream. It contains between 2 and 7 percent milk fat and at least 11 percent total milk solids.

The first step in ice cream making is formulating a suitable mix, the latter being composed of a combination of dairy ingredients, such as fresh milk and cream, frozen cream, condensed or dried skim, buttermilk, dairy whey, or whey protein concentrate. Sugars may include sucrose, corn syrup, honey, and other syrups. Stabilizers and emulsifiers are added in small amounts to help prevent formation of ice crystals, particularly during temperature fluctuations in storage.

The ice cream mix is pasteurized at no less than 79°C for 25 seconds. The heated mix is typically homogenized in order to assure a smoother body and texture.

After homogenization, the hot mix is quickly cooled to 4.4°C. The mix must age at this temperature for at least four hours to allow the fat to solidify and fat globules to clump1. This ageing process results in quicker freezing and a smoother product.

Semifrozen ice cream leaving the freezer at a temperature between -9° and -5°C is placed in a suitable container and conveyed to a blast freezer4, where temperatures are in the range of -29° to -34°C. Rapid freezing at this stage prevents the formation of large ice crystals and favours a smooth body and texture.

Much of the appeal of ice cream comes from the variety of standard mixes and flavours available throughout the year. Most ice cream manufacturers make a standard mix consisting of milk, cream, sugars, and stabilizers, to which flavours may be added just prior to freezing. There exist various types of flavours, such as high-volume flavours (vanilla, chocolate, strawberry), with large particles (fruit, nuts, cookies, or candy parts), so they are added at different stages of the process.

Being kept below -23° C and protected from temperature fluctuations, ice cream and other frozen desserts require no preservatives and have long shelf lives. Airtight6 packaging materials have made it possible to store frozen products for six months or longer without loss of flavour or body and texture.

Sherbets. They are characterized by a sweet but tart flavour and a low content of total milk solids (usually 3 to 5 percent).) Most standards require between 1 and 2 percent milk fat and between 2 and 5 percent total milk solids. Sherbet contains considerably more sugar and less air than ice cream (the target overrun is 30 to 40 percent), and therefore it is heavier and often contains more calories per serving.

Ices. Being similar to sherbet, but containing no milk solids, water ices are usually composed of sugar (30 percent), fruit juice (20 percent), flavouring, colour, stabilizer (0.2 to 0.6 percent), citric acid, and water.

Overrun in ices should be approximately 30 percent.

Answer the questions:

1) How does condensed milk differ from evaporated milk in the percentage of total milk solids and milk fat?

2) Which type of milk product (condensed/evaporated/dried) can be stored longer?

3) What kinds of dairy products can be dried?

4) What are the most desirable characteristics of frozen dessert?

5) What is the difference between plain and bulky ice creams.

6) What are the characteristics of sherbets?

7) What are ices composed of?

8) What are the steps of ice cream manufacture process?