Problem 1

Desired: 100 kg mix testing 14% fat, 10% MSNF, 15% sucrose, 0.4% stabilizer/ emulsifier.

Ingredients on hand: Butter 80% fat, skim milk powder 97% solids, water sucrose, stabilizer/emulsifier.

Solution:

1. Find the amount of butter required to supply 14 kg of fat/ 100 kg mix,

14 kg fat x 100 kg butter/80 kg fat = 17.5 kg butter

2. Find the amount of skim milk powder needed to supply a total of 10 kg of snf/ 100 kg mix.

The butter contributes 17.5 kg butter x 1.8 kg s.s / 100 kg butter = 0.315 kg s.s.

Powder must contribute 10 kg snf - 0.315 kg = 9.685 kg s.s.

9.685 kg snf x 100 kg powder/97 kg snf = 9.98 kg powder

3. Sucrose required will be 15.0 kg/ 100 kg mix.

4. Stabilizer/ emulsifier required will be 0.4 kg/ 100 kg mix.

5. The amount of water required will be equal to 100 minus the sum of the weights of the other ingredients, thus,

100 - (17.5 + 9.98 + 15 + 0.4) = 57.12 kg water

Note: In Problem 1, the serum solids content of the butter was calculated as follows: butter at 80% fat, remaining 20% skim milk at 9% milk solids-not-fat, therefore msnf in butter = 20% x 9% = 1.8%.

In the manufacture of butter, fat is churned from cream (which can be thought of as a mixture of fat and skim milk). If no washing of the butter is performed after churning, the above assumption of 1.8% msnf in 80% fat butter is correct. However, the 20% skim milk could be substituted wholly or in part with wash water, which would reduce the msnf level to anywhere between 1.8% and 0%. Each butter sample either needs to be analyzed for solids or an assumption of no msnf should be made to assure that at least the required msnf is supplied from other ingredients.

PROOF:

Ingredient Total wt. (kg) Wt. of Fat (kg) Wt. of SNF (kg) Wt. of Total Solids (kg)
Butter 17.50 14.00 0.32 14.32
Skim powder 9.98 -- 9.68 9.68
Sucrose 15.00 -- -- 15.00
Stabilizer 0.40 -- -- 0.40
Water 57.12 -- -- --
Totals 100.00 14.00 10.00 39.40

Note: 14% fat + 10% msnf + 15% sucrose + 0.4% stab. = 39.4% TS