Good to be Square?

So far this month, the UK has seen a new tax on sugar in soft drinks and a move toward the return to the old practice of charging a deposit on bottles to promote recycling.  These developments reminded me of research on the shape of food and taste perceptions, which carries mixed messages for marketers seeking to balance the need to encourage us to be green while at the same time tackling the problems of obesity.


In 2013, Cadbury’s hit the headlines when they relaunched their famous Dairy Milk chocolate and long-standing consumers complained that they had made it too sweet. Parent company Kraft responded by insisting that they hadn’t changed the recipe at all, only the packaging of the chocolate and its shape – more rounded corners on the individual pieces – had been altered. Many consumers remained suspicious, but sales weren’t effected for too long. But were these suspicions founded or not?

Of course, only Kraft will ever really know that for sure, but the literature on shape suggests they may well be telling us the truth.  A number of studies have found that food tastes sweeter when it is round in shape, or even just presented in a round container.  And the effect is not trivial – in one serious of experiments, diners reported that a bland vegetable appetiser tasted 17% sweeter when served on a round plate than it did on a square one (Fairhurst et al., 2015).

Findings such as these are helpful on some levels. We can reduce sugar and yet still maintain perceptions of taste by changing the shape of traditionally square products and making them more rounded, or even just changing the shape of the packaging or container. The round slab of toffee and the spherical Mars bar may be just around the corner!

It’s not all good news, though.  As I mentioned earlier, the sugar tax launch coincided with a move to charge deposits on bottles to encourage us to return them for recycling. A number of environmentally-minded campaigners have also been campaigning for legislation to require manufacturers to put soft drinks and water products in square bottles. The argument here is that round bottles are easier to stack, they collapse to a much more compact size when empty, and so on. All of these advantages can make recycling of square containers up to 27% more efficient than when the identical products are sold round.

As with everything in life, then, there is a trade-off. We can certainly make a dramatic impact on the carbon footprint by moving to square containers generally and a lot of research suggests that the ‘green bonus’ would be even most pronounced if this became a legal requirement for bottled drinks manufacturers. Personally, I’d caution against going down that route with carbonated drinks, however, as there may well be an unintended negative consequence for those seeking to tackle the equally worrying problem of obesity. Consumers will gradually get used to the lower sugar content of soft drinks, but forcing those drinks into square bottles may well run the risk of making them less sweet in the process – something research has already shown can actually increase the volume we consume.

Good news for the environment, but maybe not so good for our health!

Categories: Cognition, General, Motivation