Food Science

General Definition: Food science is the study of the physical, chemical, biological, and sensory properties of food, including how it is produced, processed, preserved, and consumed.

Institute of Food Technologists (IFT) Definition: “Food science is the discipline in which the engineering, biological, and physical sciences are used to study the nature of foods, the causes of deterioration, the principles underlying food processing, and the improvement of foods for the consuming public.”

FAO (Food and Agriculture Organization) Definition: “Food science is the application of scientific principles to understand the composition, structure, and behaviour of food materials and their transformations during processing, storage, and consumption.”

USDA (United States Department of Agriculture) Definition: “Food science encompasses all aspects of food, from its composition and nutritional value to safety, processing, and sensory evaluation, with the goal of ensuring a sustainable and healthy food supply.”

Academic Definition: “Food science is an interdisciplinary field that applies chemistry, microbiology, nutrition, engineering, and other sciences to develop safe, nutritious, and palatable food products.”

Introduction to Food Science

Food science is the study of the nature, composition, processing, preservation, and safety of food. It encompasses how food is produced, processed, stored, and consumed, ensuring that it meets nutritional, sensory, and safety standards. Food science bridges several disciplines, including biology, chemistry, physics, engineering, microbiology, and nutrition, to understand the transformation of raw agricultural products into consumable items.

Importance of Food in Human Life

Food plays a crucial role in human existence by:

1. Providing Energy: Carbohydrates, proteins, and fats supply calories for daily activities.
2. Supporting Growth: Proteins and minerals are essential for body development and tissue repair.
3. Maintaining Health: Vitamins, minerals, and antioxidants protect against diseases and boost immunity.
4. Ensuring Social and Cultural Connections: Food is intertwined with traditions, festivals, and social gatherings.
5. Economic and Psychological Aspects: Food production drives agriculture and the economy, while satisfying hunger enhances mental well-being.

Nutrients in Food

Food comprises six essential nutrients that serve specific functions:

1. Carbohydrates: Main energy source found in cereals, fruits, and vegetables.
2. Proteins: Required for growth and tissue repair, sourced from legumes, dairy, and meat.
3. Fats: Energy-dense nutrients essential for hormone production and skin health.
4. Vitamins: Micronutrients that support metabolism, immunity, and cell function.
5. Minerals: Inorganic elements like calcium, iron, and zinc for bone health, oxygen transport, and enzyme functions.
6. Water: Vital for hydration, nutrient transport, and cellular activities.

Branches of Food Science

1. Food Engineering: Applies engineering principles to food production, focusing on designing processing plants, machinery, and systems for efficient food processing, packaging, and distribution.
2. Food Microbiology: Studies microorganisms (bacteria, fungi, yeasts, and viruses) that affect food quality and safety. Beneficial microbes aid fermentation (e.g., in yogurt and bread), while harmful ones cause spoilage and foodborne illnesses.
3. Food Chemistry: Examines the composition of food (proteins, carbohydrates, lipids, vitamins, and minerals) and the chemical changes that occur during storage, processing, and cooking.
4. Food Technology: Focuses on applying scientific and engineering principles to food processing and preservation, ensuring food is safe, nutritious, and appealing.

Key Concepts in Food Science

1. Food Additives: Non-nutritive substances added in small quantities to improve appearance, taste, texture, or shelf life. Examples include preservatives, emulsifiers, stabilizers, and flavour enhancers.
2. Food Fortification: The addition of essential nutrients to food to improve its nutritional quality. For example, iodine in salt and vitamin D in milk.
3. Functional Foods: Foods that provide health benefits beyond basic nutrition, such as probiotics in yogurt and omega-3 fatty acids in fish oil.
4. Phytochemicals: Bioactive compounds found in plant-based foods with health benefits, such as flavonoids, carotenoids, and polyphenols.
5. Antioxidants: Compounds like vitamins C and E that protect cells from damage caused by free radicals, reducing the risk of chronic diseases.

Food Preservation and Spoilage

Food Preservation: Preservation prevents microbial growth, oxidation, and spoilage, extending shelf life while retaining nutritional value. Common methods include:

• Physical Methods: Refrigeration, freezing, drying, and irradiation.
• Chemical Methods: Using preservatives like sodium benzoate and sulfur dioxide.
• Biological Methods: Fermentation, as seen in yogurt and pickles.

Food Spoilage: Spoilage occurs due to microbial activity, enzymatic reactions, or physical changes. It results in changes in taste, smell, texture, and appearance, making food unfit for consumption.

Sensory Properties of Food

Sensory evaluation involves judging food based on its physical and organoleptic characteristics:

1. Appearance: Color, shape, and surface texture.
2. Flavor: A combination of taste and aroma.
3. Taste: Sweet, sour, salty, bitter, and umami.
4. Odor: Aroma from volatile compounds.
5. Texture: The feel of food in the mouth (crispy, soft, chewy).
6. Sound: The crunchiness of chips or the sizzle of cooking.

Physical Properties of Food

1. Boiling Point: The temperature at which a liquid turns into vapor. Pure water boils at 100°C, but adding salt raises the boiling point. This principle is used in sugar cookery and vegetable cooking.
2. Evaporation: The conversion of liquid into vapor, often used in drying foods like milk powder and preparing condensed milk.
3. Melting Point: The temperature at which a solid turns into liquid. Ice melts at 0°C, while fats melt based on their composition. This property helps in ice cream production and chocolate tempering.
4. Food Rheology: Studies the flow and deformation of food materials. Viscosity (resistance to flow) is crucial in liquid foods like sauces and soups.

Nutrition and Health

1. Nutritional Status: The condition of an individual’s health as influenced by nutrient intake and utilization. Good nutritional status supports growth, immunity, and overall well-being.
2. Malnutrition: Results from nutrient deficiency, excess, or imbalance, leading to health problems such as stunted growth, anemia, and obesity.
3. Recommended Dietary Allowance (RDA): Daily nutrient intake levels set by the Indian Council of Medical Research (ICMR) to meet the needs of healthy individuals.
4. Nutrition Surveys: Assess the dietary intake and nutritional status of a population, identifying deficiencies and planning interventions.

Food Safety and Regulation

Food safety ensures that food is free from hazards, including microbial, chemical, and physical contaminants. Regulatory bodies like the FSSAI (India), FDA (USA), and WHO establish standards and guidelines for food production, labeling, and hygiene.