How curry could reduce global warming
Feeding cattle spices could reduce methane ’emissions’
Going out for a curry can often mean spending the next day in the toilet – for humans.
For cows, though, curry spices can actually mean better digestion, reducing the enormous greenhouse gas emissions given off by grazing animals such as sheep, cows and goats, according to scientists, a report in The Independent says.
A team led by Dr Abdul Shakoor Chaudhry at the United Kingdom’s Newcastle University has found that coriander and turmeric – spices traditionally used to flavour curries – can reduce by up to 40 per cent the amount of methane that is produced by bacteria in a sheep’s stomach and then emitted into the atmosphere when the animal burps.
The spices work like an antibiotic and kill the methane-producing “bad” bacteria in the animal’s gut while allowing the “good” bacteria to flourish.
Although the research was carried out using bacteria taken from a sheep’s gut, Dr Chaudhry said the results are to be mirrored in other ruminants such as cows and goats.
Methane is a major contributor to global warming, and the slow digestive system of ruminant animals such as cows and sheep makes them a key producer of the gas, which is emitted by burping. Methane (CH4) is more than 20 times as powerful in terms of causing global warming as the main greenhouse gas, carbon dioxide (CO2).
The research has found was that certain spices contain properties which make this digestive process more efficient so producing less waste – in this case, methane.
A 2006 United Nations report said that global meat production was responsible for 18 per cent of greenhouse gas emissions – slightly more than all of the world’s cars, trains, and planes combine.
Spices have long been used safely by humans to kill bacteria and treat a variety of ailments.
The study looked at five curry spices – cumin, coriander, clove, turmeric and cinnamon. Each was “ground up” – as if chewed by the sheep – and added to an in-vitro solution mimicking that found in the rumen of the animal.
The level of methane released by each was measured against a control.
The most effective was found to be coriander, which reduced methane production from 14 millilitres per gram of food to eight – a drop of 40 per cent.
Turmeric produced a 30 per cent reduction and cumin 22 per cent.