Learn what happening in your pot when you make mozzarella cheese!

1. The Food Science Behind Mozzarella Facilitated By Norm Sutaria

2. Who is this Norm guy?

3. Not a chef by trade (but enjoys cooking) instructional designer middle school teacher AmeriCorps (twice) kayaker bike commuter curious foodie photojournalist Fringe NYC volunteer FIRST Robotics volunteer electronics hobbyist reader camper creative

4. Where did he learn to make mozzarella?

5. The Interwebs, of course.

6. Norm read a blog entry by Jenna Woginrich, a farmer, author and web designer who lives in upstate NY. http://coldantlerfarm.blogspot.com

7. This post, from September 2009, piqued his curiosity.

8. A week later….

9. he had a kit from Lehman’s, a homesteading supply shop. www.lehmans.com

10. He began making…

11. and….

12. As he was looking at this,

13. he began wondering: What is happening in my pot?

14. Which led him to research the food science behind the mozzarella he was making

15. Let’s begin with the chemical composition of milk

16. Milk is mostly made up of water, followed by non-fat solids (proteins and lactose) and then milkfat

17. 80% of the proteins found in milk are categorized as casein (kay-seen) proteins Most casein proteins exist in loose clusters known as micelles

18. 20% of the proteins found in milk are categorized as whey (way) proteins The water that is expelled in cheesemaking is called whey because it contains these proteins.

19. The chemical reaction of cheesemaking • binds proteins • encapsulates fat cells • expels whey • results in a yummy treat!

20. This is what milk looks like under a microscope at 1,000x magnification

21. Fat Globule Fat Globule Water Casein Micelles 1,000x

22. There are three elements we introduce to the milk

23. heat (to help break down proteins) food grade citric acid (to lower the pH and remove a negative charge) rennet (to break down a hairy exterior layer on the casein micelles)

24. Wait. What’s rennet?

25. Rennet is an enzyme, found in the stomach lining of mammals (typically young calves), or it can be derived from plants.

26. Chymosin (aka rennin) is the active enzyme in rennet.

27. Here’s what happens to the milk in your pot

28. The casein micelles, (simplified here), carry a negative charge and a pH of 6.5

29. Hey, you’re cute! Two Single Casein Micelles

30. Thanks! I think you are too. Two Single Casein Micelles

31. But there’s something holding me back…

32. … and I’m getting some negative vibes.

34. pH 6.5

35. Introduction of heat and food grade citric acid lowers the pH to 4.6

36. pH 4.6 heat food grade citric acid

37. Rennet (chymosin) is introduced and eliminates the hairy outside layer of the casein micelles

38. Chymosin Chymosin Chymosin Chymosin Chymosin Chymosin Chymosin Chymosin

39. Chymosin Chymosin Chymosin Chymosin Chymosin Chymosin Chymosin Chymosin Chymosin Chymosin Chymosin Chymosin Chymosin

40. Now there isn’t anything to keep us apart!

49. Casein micelles bind together, encapsulate the fat cells and expel the whey.

50. Fat Globule Fat Globule Casein Micelles Whey (expelled)

51. Finally, the kneading and stretching elongate protein chains to achieve mozzarella’s “ stringiness”

52. Yum!

53. References University of Guelph Dairy Chemistry and Physics http://www.foodscience.uoguelph.ca/dairyedu/chem.html Dr. David B. Frankhauser University of Cincinnati - Claremont College http://biology.clc.uc.edu/fankhauser/Cheese/CHEESE.HTML

54. Resources (for supplies) Lehman’s http://www.lehmans.com/ New England Cheesemaking Supply Co. http://www.cheesemaking.com/ Murray’s Cheese http://www.murrayscheese.com/