Define cheese. Explain the manufacture of cheddar cheese with suitable flow diagram.

What is Cheese?

Cheese is a dairy product derived from milk that is produced, processed, and ripened through coagulation of the milk protein casein. Milk from cows, goats, sheep, buffalo, and other mammals can be used to produce cheese. The process involves adding rennet or an acidic substance to milk, causing it to coagulate. The resulting curds are then separated from the whey, and the curds are processed to form cheese.

Cheddar Cheese Manufacture: A Detailed Look

Cheddar cheese is a relatively hard, natural cheese originating from the village of Cheddar in Somerset, England. While modern cheddar production is widespread, the traditional method involves a specific set of steps contributing to its characteristic flavor and texture.

Flow Diagram of Cheddar Cheese Manufacture

(Note: Due to the limitations of this text-based format, a diagram cannot be embedded. The above link points to a representative flow diagram of cheddar cheese making. A student should draw a similar diagram as part of their answer.)

Detailed Steps in Cheddar Cheese Manufacture

1. Milk Preparation: The process begins with milk, typically cow's milk, which is standardized for fat content. Pasteurization (heating to 72°C for 15 seconds) is commonly employed to eliminate harmful bacteria, although some traditional producers use raw milk.
2. Coagulation: Starter culture (typically Lactococcus lactis and Streptococcus thermophilus) is added to the milk. These bacteria ferment lactose (milk sugar), producing lactic acid, which lowers the pH and contributes to coagulation. Rennet (an enzyme mixture, traditionally from calf stomach) is then added to further coagulate the milk proteins, forming a firm curd.
3. Cutting the Curd: The curd is cut into small cubes (typically 1-2 cm), releasing whey. The smaller the cubes, the more whey is released, leading to a drier cheese.
4. Cooking: The curd is gently heated (typically 30-39°C) while being stirred. This process expels more whey and firms up the curd.
5. Cheddaring: This is the defining step for cheddar cheese. The curd mats (masses together) and is cut into slabs, stacked, and turned repeatedly. This process expels more whey and aligns the casein proteins, giving cheddar its characteristic texture. The cheddaring process typically lasts for 15-24 hours.
6. Milling: The cheddared curd is milled into smaller pieces.
7. Salting: Salt is added to the milled curd. Salt controls bacterial growth, helps expel more whey, and contributes to flavor.
8. Pressing: The salted curd is placed into molds and pressed to remove more whey and consolidate the cheese.
9. Ripening (Aging): The pressed cheese is removed from the molds and wrapped in cloth or waxed. It is then stored in a ripening room at a controlled temperature (around 10-15°C) and humidity for a period ranging from a few months to several years. During ripening, enzymes break down proteins and fats, developing the characteristic cheddar flavor and texture.

Factors Influencing Cheddar Cheese Quality

• Milk Quality: Fat and protein content significantly impact the cheese's flavor and texture.
• Starter Culture: Different strains of bacteria contribute unique flavor profiles.
• Rennet Type and Quantity: Affects curd formation and texture.
• Cheddaring Process: Duration and intensity influence the cheese's body and texture.
• Ripening Conditions: Temperature, humidity, and time all contribute to the development of flavor and texture.

Stage	Key Action	Impact on Quality
Coagulation	Adding starter & rennet	Affects acidity & curd firmness
Cheddaring	Stacking & turning	Impacts texture and moisture
Ripening	Controlled environment	Develops flavor and aroma