Processing of Flavored Milk

Flavored milk is a dairy product flavored with ingredients such as chocolate, strawberry, vanilla and other natural or artificial flavors. It can be made from whole milk, low-fat milk or non-fat milk depending on the fat content targeted. The most common flavors on the market are chocolate, strawberry, vanilla, banana, coffee, caramel, cookies and cream, and mint. A typical reference product (Amul Kool Elaichi Flavoured Milk) carries, per 100 ml, 89 kcal energy with 28 kcal from fat, 3.1 g total fat, 1.9 g saturated fat, 8.3 mg cholesterol, 50 mg sodium, 12 g total carbohydrate including 8 g added sugar, and 3.2 g protein; it is not a significant source of dietary fiber, Vitamin C or Iron.

The process line runs from raw milk reception and sampling and quality testing, through pre-heating at 45-50 °C, standardization for fat and SNF, sugar addition, homogenization, and pasteurization at 82±2 °C or UHT, with retorting above 121 °C where a sterilised product is required. Flavor and color are added, the milk is cooled to 4-5 °C, then filled, packed, palletized and stored. Flavors may be dosed as powders or as fruit extracts.

Two ingredient routes dominate. Fruit-flavored milk is made by adding fruit puree or fruit syrup along with other ingredients to adjust sweetness and texture; the fruit syrup should carry 45 to 55% sugar and must not contain added acid such as citric or tartaric, since acid can curdle the milk. Chocolate milk uses cocoa powder with a sweetener (sugar or corn syrup), again balanced for sweetness and texture.

Control of the plant rests on hygiene and on heat. All equipment and utensils are cleaned and sterilised before and after processing, personal hygiene regulations are strictly observed, milk is filtered after milking to remove visible dirt and any 'ropiness', and it is cooled immediately to limit microbial growth and enzyme activity. The main process control points are the temperature and time of heating and cooling: underheating leaves enzymes and micro-organisms insufficiently destroyed, shortening shelf life and raising food poisoning risk, while overheating and slow cooling alter flavour, colour and nutritional value. Packing is mainly done under aseptic conditions into polypropylene bottles, glass bottles, metal or PP cans, or tetrapacks. Sterilised product holds approximately 90-180 days at room temperature; pasteurised flavored milk holds only 5-7 days refrigerated at 4-7 °C.