Why does cream cool down chili heat?

  |   Cooking, Food, Science   |   3 Comments

I was cooking a puttanesca sauce for spaghetti recently and got a little heavy handed with the chili flakes. Personally, I can take a decent amount of heat but the rest of the – family not so much.


To avoid an ugly scene at the table I reached for the double cream to tone down the heat but not the flavour. I can’t remember how or where or when I learned this old trick, but it worked. The result was clean bowls, messy chins and I discreetly cut my portion with more ground chili without showing the others up as softies.

So what makes chilis hot?

The sensations reported as “heat” are experienced in two places – the entire oral cavity and its geographical pole, you-fill-in-the-blanks. What you are feeling is chemesthesis which is chemical irritation rather than mechanical stimulus. No matter how much heat you perceive in your mucosal membranes they will never be burned or damaged.

This is capsaicin C18H27NO3

The sensation of heat is known to food chemists as pungency and in the case of chili peppers it is caused by capasaicin. When you ingest capasaicin it binds to the neuroreceptors that also take pain signals to the brain which is why you feel the burning sensation.

The fruit of chili plants start to accumulate capsaicin from the moment of pollination up until the time they begin to to turn from green to red or orange or purple.

Capsaicin is secreted in the placenta of the chilli fruit, or the white pithy core that bears the seeds. It is expressed as droplets just under the surface. The placenta can split under pressure and release its pungent payload onto the surrounding seeds. This is why the seeds of chilli peppers are considered to be the home of the heat.



Effects of capsaicin on the body

You cannot fail to notice real metabolic changes when you eat enough capsaicin. For example, your  temperature regulation mechanisms are affected and this makes you sweat in an attempt to counteract the perception of increased body temperature and that is a very useful thing in tropical climates. It is thought that diets high in capsaicin can trigger signals of fullness, or satiety, to the brain encouraging us to eat less food and use more calories whilst doing so by the action of sweating.

How hot is hot?


While only one is a chemist, both these men have done much to advance the chili pepper’s popularity

The Scoville Scale was invented in 1912 by chemist Wilbur Scoville. He extracted the capsaicin in alcohol and rated the pungency of the increasing dilutions according to his scale. The common or garden supermarket capsicum//pepper starts with around 600 Scoville units and the notorious Scotch Bonnet pepper of the Caribbean scores 150,000. Pure capsaicin racks up a score of 16 million Scoville Units.


Why does high fat dairy dampen the burn?

Central American cuisine uses sour cream and South Asian cuisines uses yogurt for the same effect – to tone down the pungency produced by capsaicin. (However, in East Asia the options are building tolerance or exercising avoidance.) But what is the chemistry behind this?

Although I have been using the general term “capsaicin” to describe the pungency molecules, they are actually a complex of related components named capsaicinoids which are crystalline alkaloids. The alkalinity is counteracted by fermented dairy products with a lower pH, usually around pH 4-4.5. Another reason is that the capsaicin complex is slightly fatty. The long hydrocarbon chains at the end of the capsaicin molecule need to loosened with a solvent and water will not do. Nor will low alcohol drinks such as beer which will only distribute the capasaicin further around the mouth. Only dairy products containing the fat-fancying protein casein will do. The casein surrounds the fatty capsaicin molecules and pulls them away from the sites where they have bonded with the nerve receptors, in a similar way to soap washing away grease.


Ice cream will also do the trick as well, as will high alcohol spirits. I also read that bread soaked in ghee is effective, but I couldn’t possibly advise that for the sake of your arteries.


Chilis have long been valued for the flavour kick they give to staple foods such as rice and maize, but also for their anti bacterial properties and body temperature regulating powers. This is a Mexican recipe for a simple salsa that goes well with just about anything and keeps in the fridge for four or five days:


  • 5 thin chilli peppers just about to turn red
  • three spring onions
  • 3 roma or very ripe tomatoes
  • a handful of parsley or coriander
  • juice of half a lime
  • a teaspoon of sugar
  • a splash of good olive oil
  • salt and pepper

Chop all the choppable ingredients to similar sizes and combine well with everything else.


And for that Puttanesca pasta sauce that started it all, well you probably have most of these ingredients in your cupboard.

  • one shallot chopped finely
  • three cloves of garlic chopped finely
  • four anchovy fillets in oil
  • generous spoon of olive oil
  • dried chili flakes
  • 400ml of passata or a can of chopped tomatoes
  • half a glass of red wine  – Italian if you have it
  • 1 teaspoon of sugar
  • salt and pepper
  • 100g black olives halved
  • chopped parsley
  • 300g of dry, long thin pasta
  • enough for four people
  1. Heat the olive oil in a medium saucepan
  2. Add the shallots and saute for two minutes
  3. Add the anchovy fillets and stir until dissolved – they will dissolve, trust me
  4. Add the garlic and chilli flakes and stir the whole thing well until coated with the oil, this is all about flavours dispersing and bio-chemical changes in a lipid matrix – and turn up the heat to a decent saute level.
  5. Just before the garlic starts to brown add the tomatoes, wine,  salt and pepper and sugar.
  6. Bring to a boil and simmer for five minutes
  7. Throw in the olives, check the seasoning and pour on cooked pasta
  8. Garnish with chopped parsley and eat very hot



  • Paula Tucker | Oct 3, 2013 at 03:28

    Delicious! Food with a side order of chemistry

  • Christina @ The Hungry Australian | Oct 13, 2013 at 13:39

    I’m a chilli addict and you’ve now give me full permission to become an ice cream addict, too. Win! 😉

    • Crackling | Oct 13, 2013 at 17:20

      Fill your boots, Darl.

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