1.1 What is Food Made of?

The simple answer to this is chemicals and lots of them. Food is derived from plants, animals and microbes which are, in essence, highly organised chemical systems. Many of the chemicals within food are essential for human life others just happen to be associated with the material we actually want to eat. Some (flavour and texture components and colour) actually persuade us to eat the food. We choose to eat certain foods because of a combination of the chemicals they contain that give it a pleasant taste and appearance and those that we actually need in order to survive

In many instances, especially with animal-based products, many of the major chemicals that are present in the food serve the same or similar purpose in human health and maintenance of life as they did in the food when it was living. This is an important concept to bear in mind when looking at the individual components of foods and our own nutritional requirements.

The types of constituents of foods can be broadly summarised as follows:

• carbohydrates, fats and proteins the macronutrients to provide energy and the building blocks for growth, development and survival;

• vitamins and minerals which are needed in small amounts for the body to be able to function properly;

• fibre (along with other constituents) to assist in digestion and other functions;

• flavour, texture and colour compounds, which generally serve no nutritional purpose, but make the food appear and taste good;

• other compounds that either have no function...