Dairy Ingredients for Food Processing

Butter and Butter Products 207

1990 ). The main unsaturated fatty acid in

Pure butter is a monounsaturated acid (oleic

acid), hence oxidation is not a problem

(Fearon et al. 2004 ). The product commands

a premium price, while milk producers also

receive an increased payment to compensate

for higher feed costs and reward them as

members of the scheme.

An alternative approach to produce

spreadable butter within butter labeling regu-

lations has been to incorporate a lower -

melting fraction of milk fat, or a blend of

milk fat fractions, into butter or cream. Solid

fat content in milk fat from pasture - fed dairy

cows may be as high as 50% at refrigerator

temperatures, while butter produced under

winter feeding conditions (conserved forage

and concentrates) will be higher still (Figure

9.6 ). In order to achieve optimum spread-

ability in a spreadable fat product at 5 ° C

(41 ° F), it would be necessary to reduce the

solid fat content to 30% to 40%, but this must

be balanced by a solid fat content of 10% to

20% at room temperature (20 ° C; 68 ° F) to

support product body and prevent oiling off.

Blends of milk fat fractions with different

melting points seem to be preferred over

“ Pure ” naturally spreadable creamery
butter was fi rst launched under the Dromona
label by Dale Farm Limited in Northern
Ireland in 1999 (launched under the “ Pure ”
brand name in 2003), and is one of the few
dietary modifi ed spreadable butters that has
made it onto the commercial market. Dairy
cows are offered a concentrate containing
whole rapeseed during the summer months,
when the animals graze fresh grass. The com-
bination of partially protected rapeseed and
fresh grass results in milk fat with a high
content of unsaturated fatty acids, in particu-
lar C18 : 1 oleic acid, and an iodine value
of more than 45 g iodine/g fat (Fearon et al.
2004 ). The sweet creamery butter has mark-
edly improved spreadability at low tempera-
tures while maintaining product body at
room temperature.
Previous spreadable butters have been
produced by feeding large amounts of rumen -
protected polyunsaturated oils to dairy cows,
which substantially increased the content of
polyunsaturated fatty acids in the milk by
bypassing rumen hydrogenation. However,
rapid oxidation of the raw milk and butter
was a major problem (Banks and Christie

Figure 9.6. Solid fat content vs. temperature curves for winter butter, summer butter, and a blend of winter
butter and 50% vegetable oil (measured by nuclear magnetic resonance). Adapted from Fearon 1986. Fearon
and Golding (2008).

0

10

20

30

40

50

60

70

0 10203040

Temperature oC

% Solid Fat Content

Winter butter

Summer butter

Winter butter + 50% oil