Wine: Scientists reveal why cheese goes so well with vino

We all know that food is best paired with wine to delightfully complement the flavours of a meal. 

Now, French scientists have proved that the reverse is also true – fats in food interact with compounds in wine to make the drink taste better.

The researchers explored how lipids – fatty molecules abundant in cheese, meats, vegetable oils and other foods – interact with grape tannins.

Tannins are a group of bitter and astringent compounds found naturally in plants, seeds, bark, wood, leaves and fruit skins, including grapes. 

The scientists say tannins enlarge lipids, accentuating their taste and masking their undesirable bitter taste.    

The study has been led by Julie Géan and colleagues the University of Bordeaux, France. 

They say they’ve deciphered the interaction between tannins and emulsified lipids at the molecular level for the first time.  

‘Dietary oils decrease the perception of astringency of grape tannin solutions,’ the team say in the Journal of Agricultural and Food Chemistry.

‘Our results highlight that dietary lipids are crucial molecular agents impacting our sensory perception during wine consumption.’ 

It’s already established good wine can make a delicious meal taste even better, like Cabernet Sauvignon with steak. 

Researchers who specialise in the science of wine – known as enologists – have also noted mutual interactions between food and wine, such as Chardonnay and hollandaise sauce. 

Sensory analysis studies have notably shown that some foods influence the taste of wines, making them more pleasurable on the tongue. 

However, these combinations between foods and wines ‘are mainly based on empirical considerations without any scientific evidence’, the team say. 

The study authors wanted to investigate how tannins influence the size and stability of lipid droplets in an emulsion. 

They also wondered how the prior consumption of vegetable oils would impact the taste of tannins for human volunteers.

For their experiments, they made an oil-in-water emulsion using olive oil, water and a emulsifier, called DMPC phospholipid.

Olive oil provided the lipids, which are generally found as fat globules dispersed in liquids or solids. 

Then, they added a grape tannin, called catechin, and studied the lipids in the emulsion with nuclear magnetic resonance and optical and electron microscopy. 

The team found that catechin inserted itself into the layer of emulsifier that surrounded the oil droplets, causing larger droplets to form over time. 

This caused something called ‘creaming’ – the top of the emulsion (the richest in lipid droplets) turned creamy, while the bottom turned transparent. 

This result demonstrates that tannin promotes creaming, and these bigger lipid droplets mask the astringent taste of tannins.

Researchers then tried the effect in the human mouth, using three different sources of lipids.  

In taste tests, volunteers indicated that consuming a spoonful of rapeseed, grapeseed or olive oil before tasting a tannin solution reduced the astringency of the compounds. 

Olive oil had the greatest effect, causing the tannins to be perceived as fruity instead of astringent. 

In the mouth, tannins can also make oil droplets less available to bind to saliva proteins and cause astringency. 

The study highlights the importance of oils on the taste perception of the tannin solutions depends on the oil variety. 

‘Rapeseed and grapeseed oils reduce or even remove the astringency of the tannin solutions while tannin solutions are no longer perceived as astringent but as fruity after the intake of olive oil,’ the experts say. 

The team conclude that there is a ‘mutual affinity’ between tannins and lipids, as well as components of biological membranes or fatty foods. 

They believe tannin-lipid interactions should be considered by wine experts to find the best association between highly astringent red wines and fatty foods such as cheese, meat, deli meats or desserts, for example.