Can't you just take the sugar out?
Your editor recently attended a workshop presented by the Sugar Research Advisory Service. The This article is based on presentations from food technologists Richard Tupper, food technologist from Correct Food Systems and Grow Food Solutions, and the food technology team at Goodman Fielder who opened their kitchens for us to do some hands-on learning.
There are a lot of products with less or no added sugar nowadays, but removing sugar is a technical challenge in food product development and reformulation because of the many functional roles sugar performs in food. In short, you can't just take sugar out. When you do remove sugar from a recipe, you need to use more of something else and this typically means alternative sweeteners and food additives. Swapping sugar for food additives seems counter-intuitive in an age where "natural" foods are in demand, and additives can have their own adverse effects. Considering the functional cleverness of sugar, perhaps a smarter approach is to leave sugar in food to get on with its many jobs and just eat less 'sometimes foods'?
Sugar lowers the freezing point of foods so they stay soft at low temperatures, and creates a smoother texture by forming smaller ice crystals. Sugar is essential for making ice cream. Check out the label of no added sugar ice cream to see how many additives are needed to mimic the effect of sugar, including sugar alcohols that must carry a warning about their laxative effect.
Sugar suppresses sour and bitter flavours in foods, and enhances the aroma. This idea was brought to life with a taste test of natural yoghurt mixed with frozen unsweetened berries. On its own it tasted very sour, yet with a little sugar added the flavour improved significantly. Taste is king when it comes to food choice, and the most appealing foods are balanced in flavour.
Preserving is popular again with jams and jellies giving a whole new generation a lesson in the ability of sugar to reduce the growth of bacteria and moulds. It does this by reducing the 'water activity' (aw), or unbound water that can be used by bacteria, yeast and moulds. Salad dressings and mayonnaise are examples of the preserving function of sugar (in concert with vinegar and salt), and answers the question often asked as to why savoury foods contain sugar.
The maillard reaction occurs when sugars and proteins react with heat, and caramelisation occurs when sugars react with each other. Both these reactions cause browning and desirable flavours.
In both bread and cakes, sugar adds bulk and volume. In bread making, sugar provides food for yeast which then creates bubbles of carbon dioxide that allow the dough to rise. In cake making, beating sugar into butter or eggs creates tiny air bubbles which expand during baking to create a light, airy, uniform texture. Sugar also delays starch gelatinisation and protein denaturation which allows for greater volume and soft texture. Removing sugar from a cake recipe creates a flat, dense result.
Sugar when combined with pectin and acid in fruit results in a gel-like texture, such as in jam making. We saw an example of this effect when we made fruit mince tarts with sugar, and without. The fruit mince made without sugar was dry, paler in colour, and results in a much shorter shelf life.
Have you noticed that unsweetened drinks feel different in your mouth as well as taste different? This is because sugar gives liquids body or thickness. Salad dressing is another example where sugar adds body and viscosity as well as keeping qualities.
People often ask why some bread contains a little sugar and it's because it creates softness. Sugar helps keep foods moist and soft and slows staleness by attracting and binding water. The silky softness of higher sugar breads such as brioche is due to the sugar weakening the gluten structure.