The Basics of Sugar

The Basics of Sugar

For most of the world’s population, carbohydrates including sugar are an important source of energy, as well as an important ingredient in many pre-prepared foods.

Sources of Sugar

The majority of dietary carbohydrates come from plant foods. Examples of sources of sugars include:

  • Fructose - found in many fruits and in honey.
  • Glucose - small amounts are found in some plants.
  • Sucrose - derived from sugar cane and sugar beet, and also found in sweet root vegetables such as beetroot and carrots (sucrose is more commonly known as white table sugar).
  • Maltose - formed from starch in brewing.
  • Lactose - found in milk and milk products, and synthesised in the mammary gland.

There are other carbohydrates in plant foods which we do not digest, and these are major constituents dietary fibre.

Functions of Sugar

In addition to improving the taste of food, sucrose has unique properties that aid in food production. It makes specific contributions to the way foods look, taste and last on the shelf.

During the process of food production, sugar may be used as:

  • A bulking agent – contributing to the overall bulk or body of products (for example in baked goods such as meringues).
  • A fermentation agent – providing food for yeast in breads and buns in order to produce carbon dioxide to raise the dough.
  • A preservative – helping to reduce and control the growth of bacteria, mould and yeast (for example in jams).
  • A flavour enhancer – enhancing the taste of sour fruits (for example lemons or grapefruit).
  • An aid to body and viscosity in liquid and semi-liquid products (for example in syrups and sweet sauces).
  • A colour and flavouring agent – on heating, sugar caramelises to produce a desirable colour and flavour (browning).
  • A humectant – by maintaining water content, sugar extends the shelf life of foods (for example in spreads).
  • An anticoagulant – on heating, sugar delays the coagulation of protein (for example in baked custard).