The Ability Of Milk To Foam Or Froth

When coffee milk does not want to froth, these might be the reasons:

1. Proteins in milk

The protein in milk, especially the whey-proteins, is largely responsible for the foaming capacity in milk. These proteins form a film on the surface of the air bubbles in the foam. heating milk above 60°C causes the proteins to be denatured and it is more efficient in coating and stabilizing the air bubbles. UHT milk froths better than pasteurized milk, more proteins are denatured. Changes in season and what cows eat can negatively affect proteins in milk, and thus negatively effect foaming.

2. Homogenization

Homogenization improves the process of steam frothing

3. Milk fat

In general the lower the milk fat, the more foam will be formed. Skim milk will give the greatest volume of foam. This equation changes slowly when milk fat is raised above 5%. Above this value higher fat will give more foam. Breakdown of fat or lipolysis will negatively affect foaming of milk. Lipolysis generally occurs before the pasteurization of milk and is caused by the enzyme lipase. Lipolyses producers free fatty acids. Free fatty acids are surface-active agents, which depress the foaming capacity in milk. Lipolysis can occur spontaneously in milk and is aggravated by agitation. This will occur when the cow's level of nutrition is low and when she is late in lactation. This occurs in herds and regions due to feed available. This can happen during a period of adverse weather and when cows are seasonally calved. Lipolysis due to agitation commonly occurs at farm when air leaks into teat cluster and air and warm milk are vigorously mixed in milking equipment. Also occurs in factory when air is incorporated when raw milk is pumped. Lipolysis will also occur if raw milk is mixed with pasteurized / homogenized milk

4. Milk temperature

Low temperature makes milk more receptive to taking in of air

5. Mastitis

Mastitis is a infection of the udder and somatic sell counts are a indicator of the severity of the infection. Foam capacity of milk decreases as somatic sell counts increase

6. Milk solids

Milk solids have a small effect on the foaming capacity of milk. Adding solids e.g. skim milk powder can increase foaming capacity to a small degree. Adding water has little effect on foaming of milk.

7. Freshness

Refrigerated storage of pasteurized milk up to three days does not affect foaming ability.

Users Reading this article are also interested in:
Top Searches on Beverage Drink:
Pasteurized Milk Cows Milk Protein
About The Author, Leon The Milkman
Leon the Milkman is the owner of http://www.LeontheMilkman.com and http://www.dairy-info.org from where he gives a dairy dictionary and cheese tasting terms guide to new members.