Fat content and fat composition of dairy products
>Each dairy product has its own unique fat content and composition, due to several processes or factors such as cow feed composition.
>More than 200 different fatty acids are naturally present in milk.
>Milk fat is one of the most complex fat fractions found in nature.
Many health authorities recommend dairy to be part of a healthy and balanced diet due to its nutrient density. Each milk product has its own unique fat content. As milk is processed in a myriad of ways, the fat content of dairy products can range from virtually 0% to around 80%. Milk fat is composed of a broad range of fatty acids, which makes it one of nature’s most complex fatty acid fractions.
Milk fat content
The milk fat content differs within and between dairy products, see table 1.1 Raw farm milk, full-fat milk, semi skimmed milk and skimmed milk each have their own percentage of fat. Raw milk has an average fat content of 4.4g of milk fat per 100g, and can be skimmed to obtain full fat and lower fat varieties. Full-fat milk is standardised to 3.5% of fat and semi skimmed milk contains approximately 1.5% fat. Skimmed milk and buttermilk are very low in fat and, on average, contain 0.1 or 0.2% fat respectively. Due to international differences in standardisation however, the fat percentage for (semi)-skimmed, whole milk and buttermilk can vary according to country.
Yoghurt and cheese
Yoghurt is produced by acidifying skimmed, semi skimmed or whole milk using lactic acid bacteria. The fat content is therefore almost similar to the milk it is made from, ranging roughly from 0.2% to 3% fat. Cheese always has a notably higher fat content, although the range is broad. For example, cottage cheese – with a high moisture content – has a relatively low fat percentage (80% water, 4.3% fat). Matured hard cheese, such as regular parmesan, is low in moisture and therefore has a relatively high fat content (40% water, 30% fat), see also annex I.2
Cream is produced by skimming the layer of fat from milk before homogenization. Cream’s fat content can vary per country, but full-fat cream or heavy cream usually has a fat content of about 35%. Cream can be churned into butter, serving to further lower its moisture content and coagulate the milk fats and proteins. Butter usually contains around 80% fat.
Table 1: Amounts of fat in dairy products1
|Product||Energy (kcal/100g)||Fat (g/100g)||Saturated fatty acids (g/100g)||Monounsaturated fatty acids (g/100g)||Polyunsaturated fatty acids (g/100g)||Trans fatty acids (g/100g)|
|Milk, full fat||66||3.9||2.5||1.0||0.1||0.1|
|Milk, semi skimmed||46||1.7||1.1||0.4||Tr||0.1|
|Yoghurt, full fat||79||3.0||1.7||0.9||0.2||N|
|Cheese, Gouda 48+
Milk fat composition
Milk fat is composed of a broad range of fatty acids, which makes it one of nature’s most complex fatty acid fractions. More than 200 different fatty acids are naturally present in milk.
Fat in milk
The actual fat content and composition of milk varies naturally due to several factors, including cow feed composition, which differs in summer and winter, and the amount of time cows spend grazing, as well as intrinsic differences between cows.3 The relatively small amount of fat in milk is quite complex when compared to the fat profile of some major plant fats and oils, even if the major fatty acids are the only ones taken into account, see table 2 for a comparison on the major fatty acids.4
Table 2: Fatty acid composition of milk fat* and a selection of plant oils4
|Food sources||SAFA – short and medium chain length (g/100g)**||SAFA – long chain length (g/100g)***||Monounsaturated fatty acids (g/100g)||Polyunsaturated fatty acids (g/100g)||Trans fatty acids (g/100g) ****|
|Milk – summer*||13||53||26||3||3|
|Milk – winter*||11||60||21||2||2|
|Palm kernel oil||4||75||15||2|
**Short + medium chain SAFA = C4-C10
***Long chain SAFA = C12-C22
****Excludes Conjugated Linoleic Acid, which is 1.3 g (own factory milk – summer) and 0.7 g (own factory milk – winter)
Milk fat blend
In the milk fat blend, saturated fatty acids make up roughly 60-70% of the total fat content. The remaining 30-40% fats are unsaturated fatty acids, and to a large extent oleic acid, a monounsaturated fatty acid. Milk fat also contains some polyunsaturated omega-6 and omega-3 fatty acids, but these are present only in relatively small quantities. Milk fat generally contains around 1.3% linoleic acid and 0.5% alpha linolenic acid, with concentrations that can increase significantly in spring and summer compared to autumn and winter.3,5 Milk and dairy products also contain small quantities of natural polyunsaturated acids with a trans and a cis binding, which are commonly referred to as conjugated linoleic acid.
Water, protein and fat content (g/100g) of a selection of cheese varieties2
- R.A. McCance and E.M. Widdowson, McCance and Widdowson’s The composition of Foods. Sixth summary ed. 2002: Cambridge: Royal Society of Chemistry.
- P. Walstra et. al., Dairy science and technology. 2nd ed. 2006.
- J.M. Heck JM et al., Seasonal variation in the Dutch bovine raw milk composition. J Dairy Sci, 2009. 92(10): p. 4745-55.
- Own data FrieslandCampina, 2007.
- H.J. van Valenberg, et al., Concentrations of n-3 and n-6 fatty acids in Dutch bovine milk fat and their contribution to human dietary intake. J Dairy Sci. , 2013. 96(7): p. 4173-81.