nutrition food science

INTRODUCTION TO FOOD SCIENCE

Civilized man modifies food through cutting, crushing, cooking, and processing to add variety to the diet and enhance its safety and nutritional value.

DEFINITIONS

Food: Any solid or liquid that, when swallowed, digested, and assimilated, nourishes the body, providing essential nutrients necessary for growth, maintenance, and overall health.
Food Science: Involves understanding the biochemical, physical, and nutritional changes occurring in food components during preparation, whether natural or induced by various handling procedures (e.g., cooking, preservation, processing).
Many physical and chemical reactions occur during food preparation due to interactions between various food components (like proteins, fats, carbohydrates) and cooking conditions (heat, cold, light, air).
Food Additives: Non-nutritive substances added intentionally to food in small quantities to improve appearance, flavor, texture, or storage properties. They can also include preservatives that inhibit spoilage, antioxidants that prevent rancidity, and emulsifiers that improve consistency.
Fermented Food: Produced through the metabolic activity of microorganisms such as bacteria or molds acting on carbohydrates and proteins, yielding predigested foods that are often more nutritious and easier to digest (e.g., yogurt, sauerkraut).
Food Technology: The application of food science principles combined with engineering practices to develop processes for food preservation, packaging, and distribution at a large scale.
Food Fortification: A process defined by the WHO that involves adding specific nutrients to food to enhance its nutritional value and improve overall diet quality, aiming to prevent deficiencies in populations.
Biofortification: The process of improving the nutrient content of crops through selective breeding or genetic modification techniques, targeting essential vitamins and minerals.

FOOD CHEMISTRY

Investigates the composition, structure, and properties of foodstuffs and their components, including interactions among macronutrients and micronutrients.

Non-nutrients: Organic compounds that lack direct nutritional function, which may include environmental or naturally occurring toxins, as well as beneficial substances like dietary fiber that contributes to various health benefits.
Functional Food: Foods that offer health benefits beyond basic nutrition when consumed regularly in adequate amounts; these foods may influence biological activity positively in the body (e.g., probiotics, omega-3 fatty acids).
Phytochemicals: Non-nutrient bioactive compounds found in plant-derived foods that possess antioxidant and anti-inflammatory properties, contributing to the prevention of chronic diseases.
Food Safety and Regulation: Ensures food sanitation standards and protection of public health, focusing on preventing harmful processes or reactions that could lead to foodborne illnesses.
Antioxidants: Compounds that protect biological systems from excessive oxidation processes, potentially lowering the risk of chronic diseases and promoting health through anti-inflammatory actions.

FUNCTIONS OF FOOD

Energy Yielding Foods: Broadly categorized into carbohydrates, fats, and proteins, which provide energy essential for bodily functions (e.g., 1 g of protein and carbohydrates = 4 calories; 1 g of fat = 9 calories). Sources include cereals, pulses, nuts, oilseeds, roots, and tubers.
Body Building Foods: Rich in protein and classified into two groups:
- High Biological Value Proteins: Include complete proteins found in animal products such as milk, eggs, meat, and fish.
- Lower Biological Value Proteins: Found in plant sources like pulses, oilseeds, and nuts; although they usually lack one or more essential amino acids.
Protective and Regulatory Foods: These foods aid in bodily functions, such as maintaining heart rate and body temperature, and include high-protein foods and those rich in vitamins and minerals (e.g., milk, green leafy vegetables, fruits).

MAINTENANCE OF HEALTH

Certain phytochemicals and antioxidants play a key role in preventing degenerative diseases and cancers by modifying risk factors. Functional foods include whole grains, soybeans, green leafy vegetables, fruits, and spices, all of which support health through various mechanisms.

FOOD GROUPS (ICMR Classification)

Cereals, Millets, and Pulses: Key sources of energy, protein, and essential nutrients, forming a foundation for many diets worldwide.
Milk and Animal Products: Major sources of high-quality protein, fat, and essential minerals, contributing significantly to daily calorie intake.
Vegetables and Fruits: Vital for providing a wide range of vitamins, minerals, and dietary fiber, necessary for digestive health and disease prevention.
Oils, Fats, and Nuts: Essential for providing necessary fatty acids and fat-soluble vitamins, crucial for overall health and energy balance.

FOOD PYRAMID GUIDELINES

The ICMR recommends a balanced diet with proportional consumption: adequate cereals and pulses; liberal amounts of fruits and vegetables; moderate intake of animal foods; and sparing use of oils and sugars to promote health and well-being.

FOOD IN RELATION TO HEALTH

Emphasizes the importance of a balanced diet to meet nutritional needs and prevent deficiencies, with tables showing common nutrient deficiencies and their food sources to guide healthy eating choices.

COOKING

Cooking combines various food ingredients, enhances flavors, improves food safety, and increases digestibility, thus enhancing the overall eating experience.

OBJECTIVES OF COOKING

Improvements in cooking aim for enhanced taste and overall food quality; destruction of harmful microorganisms; and improved nutrient availability, as cooking can denature compounds that inhibit nutrient absorption (e.g., cooking beans removes trypsin inhibitors).

PRELIMINARY PREPARATIONS

Pre-cooking tasks include cleaning, peeling, cutting, grating, sieving, soaking, and marinating food to ensure safety and improve culinary outcomes.

Cleaning: Vital for removing dirt, chemicals, and insects from fruits and vegetables. Washing can significantly reduce pesticide residues and pathogens present on the surface.
Peeling and Stringing: Helps discard inedible parts of food, although preparing foods this way may lead to some nutrient loss, especially in the skin.
Cutting and Grating: Facilitates cooking and improves food appearance, yet increases surface area, which may lead to greater nutrient loss if not prepared carefully.
Sieving: Removes impurities and can enhance the shelf life of ingredients, particularly for flour, ensuring quality for cooking and baking.