Optimizing Butter Making Laura Kelley and Mohammad Biswas CHEN 3820 Chemical Engineering Lab 1 April 24, 2007

Buttery Facts Butter is made by the agitation of the cream layer from unhomogenized milk. Butter has been made for many centuries in the same fashion, but technological advancements have lead to faster ways to make butter. Our project involves making butter by varying temperature and adding co-solvents.

Background: How to Make Butter Milk: Basis of Butter –Milk is an emulsion of fat globules within a water based fluid –Milk consists mostly of water –Fat separates from the milk to form cream layer –This layer is more concentrated in fat than the milk Reference: Milk Content, April 22, 2007http://en.wikipedia.org/wiki/Milk Milk Content Analysis, per 100 grams

Background: How to Make Butter Churning: Means to Butter –Early period butter making process –Collect the cream layer from the milk –Allowed to sour over a couple of days at room temperature –Use Butter Churn to produce butter and buttermilk –Remove butter from buttermilk and rinse with cold water –Add salt to butter for preservation

How We Made Butter Main Ingredient: –Heavy Whipping Cream Methods Used: –Electric Mixer –Manual Shaking Agitation causes physical separation of butter and buttermilk

Stages of Butter Churning Heavy Cream Layer –This was obtained after separation of the milk emulsion –Agitation begins at this stage Whip Cream –Stiff peaks form –This is what is purchased at stores after adding other ingredients

Stages of Butter Churning Transition Stage –Butter begins to form –Appearance of the signature pale yellow color Final Stage: Butter –Formation of clumps –Separation of butter and buttermilk –Wash butter to remove excess buttermilk for storage

Experiment 1: Different Ingredients Main Ingredient: –Heavy Whipping Cream Co-solvents Examined: –Salt –Calcium Supplements (Calcium Sulfate) –Baking Powder –Cornstarch –Sugar

Results of Experiment 1

Experiment 2: Addition of Salt Amount of Salt for every two cups (~ 460 g) of heavy cream: –½ teaspoon (2.4 grams) –1 teaspoon (4.7 grams) –1 tablespoon (14.2 grams) –2 tablespoons (28.5 grams) –3 tablespoons (42.7 grams)

Results of Experiment 2

Experiment 3: Temperature Temperature Variation: –0 o C –10 o C –Room Temperature –30 o C Determine the role of temperature on the formation of butter

Results of Experiment 3

Conclusions Butter can be produced the fastest with an ionic co-solvents Increasing the amount of co-solvent does not always decrease the time to make butter Ideal conditions to make butter is at room temperature

Questions? References –Cooking for Engineers, April 2, 2007 –Milk, April 22, 2007 Now let us have some Bread and Sweet Butter