Kerry E. Kaylegian, Ph.D. May 2014

What is Cheese?

Fermented Products Yogurt Buttermilk Acidophilus Milk Kefir, Koumiss Sour Cream Cream Cheese Cheddar, Colby Mozzarella, Provolone & Italian types Emmental, Gruyere & Swiss types Brie, Camembert Blue cheeses Munster, Brick Frozen Desserts Ice Cream Gelato Sherbet Other Flavored Milks Pudding Creams Butter

Dairy Fermentation Milk Bacteria Molds Yeasts Microbial Metabolism Processing Conditions ++ Products with a Variety of Flavors, Textures & End Uses

Variables in Cheesemaking Type of cheese Type of milk Milk composition Heat treatment Microorganisms used Time Temperature pH Salting method Other handling Other ingredients Environment –sanitation –water quality –native flora (good & bad) –storage temperature –storage humidity Production consistency –acidity development –flavor & texture

Defining Varieties … By Manufacturing Technique Acid set Rennet set Fresh/Aged Cheddar type Pasta filata Cheese with eyes Natural rind Washed-rind Mold-ripened By Cheese Characteristics Fresh Semi-soft Soft-ripened Surface-ripened Semi-hard Hard Blue Washed-rind Milk type (cow, goat, sheep)

How can you govern a country that has 246 varieties of cheese? Charles de Gaulle French President, : 1794 entries (cheese, yogurt, butter), 100 categories 2012: World Championship, 2504 entries, 81 categories 2013: US Championship, 1702 entries, 81 categories 2014: World Championship, 2619 entries, 90 categories (cheese, butter)

Cheese Standards Code of Federal Regulations –21 CFR cfm?cfrpart=133 –contains Standards of Identity (SoI) for many cheeses –regulations can be very specific on cheese composition, make procedures and ingredients Pennsylvania Code –Title 7 Part III Ch. 57 –§ Cheese and related cheese products Cheese and related cheese products shall comply with 21 CFR 133 (relating to cheese and related cheese products).

Cheddar Cheese Standard 21 CFR

Cheese – Pasteurized or Raw 7 CFR 58

General Cheese Making Steps Raw Milk Pasteurize/Heat Inoculate with Starter & Non-Starter Bacteria and Ripen Add Rennet and Form Coagulum Cut Curd & Cook Drain Whey Texture Curd Dry Salt/Brine Form Cheeses Store and Age

Major Steps in Cheese Making StepPurposeKey Factors Setting MilkPrepare milk for coagulation Ripen starter culture Coagulation Temperature Protein Calcium Sanitation (phage)

Coagulation Acid Coagulation Function of isoelectric properties at pH 6.6 the net charge on the proteins is negative, casein micelles repel pH 4.6 is the isoelectric point and the net charge is neutral, casein micelles interact soft, delicate curds –at lower pH, the casein micelles are depleted of Ca Rennet Coagulation Function of enzyme activity 1 st step cleaves  -casein –net negative charge is reduced –steric repulsion is decreased 2 nd step requires ionic (free) Ca –Ca forms bridges to stabilize the aggregation firmer, stronger curds –at higher pH, the Ca is still present in the casein micelles

Major Steps in Cheese Making StepPurposeKey Factors Setting MilkPrepare milk for coagulation Ripen starter culture Rennet coagulation Temperature Protein Calcium Sanitation (phage) Cutting the Curd Speed whey expulsion Assist in uniform cooking Assist with moisture control Curd firmness Size of curd particles Uniformity of curd particles

Major Steps in Cheese Making StepPurposeKey Factors Setting MilkPrepare milk for coagulation Ripen starter culture Rennet coagulation Temperature Protein Calcium Sanitation (phage) Cutting the Curd Speed whey expulsion Assist in uniform cooking Assist with moisture control Curd firmness Size of curd particles Uniformity of curd particles Cooking the curd Remove whey Establish moisture level in cheese Influence texture Curd size Time & temperature profile Stirring rate pH

Major Steps in Cheese Making StepPurposeKey Factors Setting MilkPrepare milk for coagulation Ripen starter culture Rennet coagulation Temperature Protein Calcium Sanitation (phage) Cutting the Curd Speed whey expulsion Assist in uniform cooking Assist with moisture control Curd firmness Size of curd particles Uniformity of curd particles Cooking the curd Remove whey Establish moisture level in cheese Influence texture Curd size Time & temperature profile Stirring rate pH Draining or Dipping Separate whey from curds Moisture control pH

Major Steps in Cheese Making StepPurposeKey Factors Curd KnittingForm characteristic texture Acid development Moisture control Temperature Time

Major Steps in Cheese Making StepPurposeKey Factors Curd KnittingForm characteristic texture Acid development Moisture control Temperature Time PressingExpel whey Shape cheese Influence texture Temperature Pressure Acidity development

Major Steps in Cheese Making StepPurposeKey Factors Curd KnittingForm characteristic texture Acid development Moisture control Temperature Time PressingExpel whey Shape cheese Influence texture Temperature Pressure Acidity development SaltingInfluence flavor Influence texture Control moisture Method of salting Curd size Temperature

Major Steps in Cheese Making StepPurposeKey Factors Curd KnittingForm characteristic texture Acid development Moisture control Temperature Time PressingExpel whey Shape cheese Influence texture Temperature Pressure Acidity development SaltingInfluence flavor Influence texture Control moisture Method of salting Curd size Temperature Special Applications Apply appropriate practices to give cheese its characteristics (pasta filata, mold-ripened, washed-rind, aged) Depends on the application

Flavoring Cheese Herbs Spices Fruit pieces Vegetable pieces Smoke Beer Wine (Microbial smears)

Washed-Rind Cheese Outer surface flavor & color –beer Chimay Ale –wine Drunken Goat Complex flavor & rind development –microbial smears (Brevibacterium linens) –yeasts –sequence of organism development –specific to organisms used

Cheese Aging = Affinage The ripening of a young cheese to a mature cheese –development of complex flavors and textures

Cheese Aging Cheese Variables –cheese type –microflora Environment Variables –temperature –humidity –air flow –air turnover –shelving type –proximity to other cheeses –native flora –sanitation Handling –time –turning –brushing –washing –sanitation

Cheese Aging – Environmental Conditions Drying –57-64°F, 60-80% RH Ripening –52-77°F, natural rind cheeses –46-52°F, bloomy cheeses –46-48°F, blue cheeses –90-98% RH, natural rind cheeses Warm (eye development) –68-72°F, 80-85% RH Cool storage –38-48°F, flavor development –38-40°F, 60-80% RH, storage prior to sale –90-95% RH, natural rind cheeses

Cheddar Type Cheese Make Steps Raw Milk Pasteurize/Heat Inoculate with Starter & Non-Starter Bacteria and Ripen Add Rennet and Form Coagulum Cut Curd & Cook Drain Whey Texture Curd Dry Salt Form Cheeses Store and Age Lactococcus lactis subsp. lactis or cremoris pH °F (38°C) Cheddaring & Milling OR Stirred Curd pH 5.1 – 5.5 Hoop & Press 1 month to 5+ years Lactobacillus casei, Lactobacillus plantarum ° F (30-32°C) Wash curd for Colby & Jack

Cheese with Eyes Make Steps Raw Milk Pasteurize/Heat Inoculate with Starter & Non-Starter Bacteria and Ripen Add Rennet and Form Coagulum Cut Curd & Cook Drain Whey Texture Curd Brine Form Cheeses Store and Age °F (48-52°C) rapid cook S. thermophilus, L. helviticus L. delbrueckii subsp. bulgaricus Proprionibacterium freudenreichi pH 6.4 cheeses placed in hoops before draining curd is pressed in hoops, acid begins to form pH °F (15°C), 2 d 1-2 wk, 60°F (15°C) drying 3-7 wk, 70-77°F (21-25°C) eye formation 4-12 wk, 41°F (5°C) aging

Blue Veined Cheese Make Steps Raw Milk Pasteurize/Homogenize/Heat Inoculate with Starter & Non-Starter Bacteria and Ripen Add Rennet and Form Coagulum Cut Curd & Cook Dip Curd/Form Cheese Texture Curd Dry Salt/Brine Drain Whey Store and Age L. lactis subsp. lactis L. lactis subsp. cremoris 1 hr 90°F (32°C) firm curd, open texture put into hoops drain 1-7 d, 68°F (20°C), 80% RH pierce with needles Penicillium roqueforti spores ripen and cure 50-60°F (10-15°C), 95% RH mold growth 2-4 mo cure 2-4 mo

? Kerry E. Kaylegian, Ph.D. Dairy Foods Research & Extension Associate Pennsylvania State University Department of Food Science foodscience.psu.edu