Essential Concepts of Food Science and Human Nutrition

Fundamentals of Food and Nutrition

Food

We consume foods that make up our diet and are essential for proper nutrition.

Nutrition

The set of processes by which the body obtains the material and energy needed to build its own tissues and perform vital functions.

Organic Nutrients: Structure and Function

The primary organic nutrients required by the body are carbohydrates, lipids, and proteins.

• Carbohydrates

  Carbohydrates are the most abundant nutrients in food. The simplest forms are sweet, including glucose and sucrose.

• Lipids (Fats)

  Lipids are nutrients that are not dissolved in water (hydrophobic). They provide concentrated energy. Vegetable lipids are typically liquid and are called oils. Solid lipids are known as fats or tallow.

• Proteins

  These are macromolecules formed by smaller units called amino acids. Proteins provide the structural material for cell formation and perform crucial functions, such as carrying oxygen in the blood.

Key Metabolic Definitions

Calorie

The amount of heat energy required to raise the temperature of one gram of water by one degree Celsius (centigrade).

Basal Metabolic Rate (BMR)

The rate at which our body burns calories in a day while in complete rest and maintaining a constant temperature.

Diet and Healthy Eating

Diet refers to the set of solid and liquid substances we consume as food throughout the day. A diet may be specific to each person based on factors such as age, weight, sex, and activity level. To lead a healthy lifestyle, our diet must be complete, varied, and balanced.

Common Feeding and Eating Disorders

The most common health issues related to food intake include:

• Malnutrition

  Caused by a lack of essential nutrients due to an inadequate diet.

• Obesity

  Consists of an excessive accumulation of body fat.

• Anorexia Nervosa

  Characterized by an intense fear of gaining weight and a severely distorted perception of one's body shape and size.

• Bulimia Nervosa

  Also characterized by an excessive preoccupation with weight and body shape, often involving cycles of binge eating and compensatory behaviors.

Food Preservation and Handling Techniques

Methods for safe storage and handling of food:

• Cold Storage

  Foods are maintained at low temperatures to slow microbial growth.

• Conservation Using Heat

  Foods are preserved using high temperatures for a specific period to eliminate or reduce microorganisms.

  1. Pasteurization

     Involves heating food (typically liquids like milk) to temperatures below 100°C for a short time to destroy pathogens while minimizing changes to flavor and nutritional value.

  2. Sterilization

     Applying temperatures above 100°C for a sustained time to eliminate all forms of microbial life, including spores.

• Conservation by Dehydration

  Based on the elimination of water content from food, which inhibits microbial development.

• Conservation by Addition of Substances (Curing/Pickling)

  Incorporating different substances (like salt, sugar, or vinegar) into the food to prevent the development of microorganisms.