Food Commodities: Cheese

Cheese: Nutritional and Dietetic Value

Nutritional Value of Cheese

Types of Protein

• Casein and Whey Proteins: Cheese is a rich source of high-quality proteins, primarily casein, and whey, essential for growth, repair, and maintenance of body tissues.
• Amino Acids: These proteins provide all the essential amino acids necessary for human health.

Types of Fat

• Saturated Fats: Most cheeses contain high levels of saturated fats, which should be consumed in moderation due to potential impacts on heart health.
• Unsaturated Fats: Some cheeses, especially those made from milk of grass-fed animals, may contain higher levels of omega-3 fatty acids.

Vitamins and Minerals

• Calcium: Cheese is a significant source of calcium, vital for bone health.
• Vitamin B12: Often found in cheese, this vitamin is crucial for red blood cell formation and neurological function.
• Other Nutrients: Cheese also provides phosphorus, zinc, vitamin A, riboflavin, and vitamin K2.

Dietetic Value of Cheese

Bone Health

• The high calcium content supports bone density and health.

Satiety

• High protein and fat content can promote satiety, helping in weight management.

Dental Health

• Cheese can increase saliva flow, reducing the risk of cavities.

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Food Commodities: Cheese

High in Saturated Fat

• Can contribute to high cholesterol and heart disease if consumed in excess.

Lactose Intolerance

• Some people may have difficulty digesting lactose found in cheese. Lactose-intolerant individuals might choose aged cheeses, which are typically lower in lactose.

High in Sodium

• Certain cheeses are high in sodium, which can be problematic for blood pressure.

Vegetarian Diet

• A good source of protein and vitamins for vegetarians.

Exam Focus: Questions and Answers

1. Discuss the nutritional value of cheese, focusing on its protein content.

Cheese is an excellent source of high-quality proteins, primarily casein and whey, which are essential for the growth, repair, and maintenance of body tissues. These proteins provide a complete set of essential amino acids needed for various bodily functions, making cheese an important dietary component, especially in vegetarian diets.

2. Evaluate the dietetic value of cheese, including its advantages and disadvantages.

The dietetic value of cheese lies in its high calcium and protein content, promoting bone health and satiety, which can aid in weight management. However, its high saturated fat and sodium content can be a disadvantage, potentially impacting heart health and blood pressure. It's suitable for a varied diet but should be consumed in moderation. For lactose-intolerant individuals, aged cheeses with lower lactose levels are preferable.

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Food Commodities: Cheese

Production of Cheese

Steps in Cheese Production

1. Pasteurization

• Definition: Pasteurization involves heating milk to destroy harmful bacteria.
• Process: Milk is typically heated to about 72°C for 15 seconds and then rapidly cooled.
• Purpose: This process ensures the safety and extends the shelf life of the cheese.

2. Adding Starter Cultures

• Cultures: Specific bacteria are added to the milk to begin the fermentation process.
• Lactic Acid: These bacteria convert lactose in the milk into lactic acid, which begins to curdle the milk.

3. Addition of Rennet

• Rennet: An enzyme, traditionally sourced from the stomachs of ruminants, is added.
• Coagulation: Rennet causes the milk to coagulate, forming a solid mass (curd) and liquid (whey).

4. Separation of Curds and Whey

• Separation: The solid curds are separated from the liquid whey.
• Types of Cheese: The treatment of curds at this stage can lead to different cheese textures and flavours.

5. Cutting the Curd

• Process: The curd is cut into smaller pieces, increasing the surface area.
• Effect: Cutting the curd allows more whey to drain from it, impacting the final cheese's moisture content.

6. Draining

• Draining Whey: The whey is drained off, leaving the curd behind.
• Texture: The extent of draining affects the cheese's texture; more draining results in a harder cheese.

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Food Commodities: Cheese

7. Scalding

• Heating: The curds are gently heated (scalded), often up to temperatures of about 39°C.
• Purpose: This process expels more whey and hardens the curd, affecting the final cheese's texture.

8. Cheddaring

• Specific to Cheddar: A process where the curd is cut into slabs, stacked, and turned.
• Texture: Cheddaring expels more whey and develops the unique texture and flavour of cheddar cheese.

9. Milling into Curd Chips

• Milling: The curd is cut into smaller pieces, known as curd chips.
• Ageing Preparation: This step prepares the curd for ageing and allows for more even salt absorption.

10. Adding Salt

• Flavour and Preservation: Salt is added for flavour and acts as a preservative.
• Moisture Control: Salt also helps to control moisture and the activity of bacteria in the cheese.

11. Pressing and Shaping

• Forming: The curd is placed into moulds and pressed to expel remaining whey and shape the cheese.
• Consistency: Pressing impacts the cheese's final texture and density.

12. Ripening/Ageing

• Ageing: Cheese is aged or ripened under controlled conditions for varying periods, depending on the type.
• Flavour Development: Aging develops the flavour and texture characteristics of the cheese.

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Food Commodities: Cheese

13. Packaging and Labelling

• Protection: Cheese is packaged to protect it from contamination and moisture loss.
• Information: Labels provide information on the type of cheese, ingredients, nutritional content, and expiration date.

Exam Focus: Questions and Answers

1. Explain the importance of pasteurisation in the cheese-making process.

Pasteurisation is crucial in cheese production as it involves heating milk to around 72°C for 15 seconds to destroy harmful bacteria. This process ensures the safety of the cheese and extends its shelf life by preventing spoilage and the growth of pathogens.

2. Describe the process of curd formation in cheese-making.

Curd formation in cheese-making begins with the addition of starter cultures that convert lactose into lactic acid, starting the curdling process. Then, rennet is added, which coagulates the milk, separating it into solid curds and liquid whey. The curds are then cut, drained, and scalded, further expelling whey and hardening the curd, which is crucial for developing the cheese's texture and moisture content.

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Food Commodities: Cheese

Cheese: Buying, Storing, Uses, and Cooking

Guidelines for Buying Cheese

Types of Cheese

• Varieties: Understand the different types of cheese available, such as soft, semi-soft, hard, and blue-veined, and their unique characteristics.
• Flavour Profile: Choose based on the desired flavour intensity, ranging from mild to strong.

Freshness and Quality

• Appearance: Look for cheese that appears fresh, without cracks or dry edges.
• Packaging: Ensure the packaging is intact and the cheese is well-protected.

Special Considerations

• Origin: Consider the origin of the cheese; certain regions are renowned for specific types of cheese.
• Artisanal vs Commercial: Decide between artisanal cheeses, which may offer unique flavours, and commercial ones, which are more standardised.

Guidelines for Storing Cheese

Temperature and Humidity

• Refrigeration: Most cheeses should be stored in the refrigerator at a temperature of around 4°C to 8°C.
• Humidity: Cheese prefers a humid environment; a vegetable drawer can often provide this.

Packaging

• Wrap Properly: Cheese should be wrapped in parchment or wax paper followed by a loose layer of plastic wrap.
• Avoid Airtight Containers: Airtight containers can promote moisture build-up and mould growth.

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Food Commodities: Cheese

Handling Leftovers

• Re-wrapping: Rewrap cheese in new parchment paper after each use to prevent the cheese from drying out or absorbing other flavours.

Culinary Uses of Cheese

As a Main Ingredient

• Cheese Boards: An assortment of cheeses served with crackers, fruits, and nuts.
• Grilled Cheese Sandwiches: A classic dish using melted cheese.

In Cooking and Baking

• Melting: Used in dishes like fondue, pizza, and casseroles.
• Baking: Incorporated into pastries, bread, and cheesecakes.

Flavour Enhancer

• Topping: Grated cheese as a topping for pasta, salads, and soups.
• Stuffing: Used as a filling in meats and vegetables.

Effects of Cooking on Cheese

Melting Characteristics

• Melting Points: Different cheeses melt at different temperatures due to their fat and moisture content.
• Stretchiness: Mozzarella is prized for its stretch when melted, ideal for pizzas.

Texture Changes

• Softening: Heat softens cheese, making it ideal for spreading or incorporating into sauces.
• Browning: Some cheeses, like Parmesan, can develop a crispy, browned crust when cooked.

Flavour Development

• Intensification: Cooking can intensify the flavour of cheese.
• Complexity: Roasting or grilling cheese can add a smoky, complex flavour profile.

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Food Commodities: Cheese

Exam Focus: Questions and Answers

1. Explain the key considerations when buying cheese.

When buying cheese, it's important to consider the type of cheese based on flavour preference and culinary use, ranging from soft to hard varieties. Assessing the freshness and quality is crucial, looking for cheese with a fresh appearance and intact packaging. Additionally, understanding the origin and choosing between artisanal and commercial cheeses can enhance the selection process based on desired flavour profiles and quality standards.

2. Describe how cooking affects the texture and flavour of cheese.

Cooking affects cheese primarily by changing its texture and flavour. The heat softens cheese, which can enhance its spreadability and incorporation into sauces. Different cheeses have varying melting points, affecting their suitability for certain dishes, like pizzas or fondue. Cooking can also intensify and add complexity to the flavour of cheese, with processes like roasting or grilling adding a smoky taste. Some cheeses, when cooked, can develop a crispy, browned crust, adding a different texture dimension to dishes.