A more sustainable way of cooking pasta
Around the world, people eat 17 million tons of pasta every year, or 17.000.000.000.000 kg. That’s a lot!
As an Italian and a big pasta consumer, I thought that finding sustainable ways of cooking pasta could be fun. On average every Italian eats 23.5 kg of pasta every year (more than other country ofc).
The pasta industry is sustainable, it produces only 150g of CO2 equivalent for a portion. But 38% percent of the footprint comes from cooking it at home. So is there any way to reduce this emission by just changing people’s practices?
By doing some research three variables can help this:
1. the lid
2. the water quantity
3. time of cooking
4. energy efficiency
Keep the lid on all the time
Keeping the lid on the pan limit the exchange of heat with the air and creates a bigger pressure inside the pan. Pressure and insulation reduce the boiling time of water and reduce the emission by about 6%.
Use the right water quantity
It’s possible to use only 700ml of water to cook one portion of pasta. Grandma used to say that we only need 1l for 100g of pasta, but today pasta releases less starch so we can use less water. This can save 13% of emissions and also save water (a good idea with the latest water scarcity!). Also using more water than we need uses a lot more energy.
Passive cooking
Disclaimer: maybe some Italian will insult me for writing this but there is a lot of documentation online that proves this…
After we pour the pasta, we wait two minutes so the water boils again, we leave the lid on and turn off the stove. We only have to wait until the cooking time and the pasta will be ready. Wait what?
Let me explain why this work. The first time I heard this was a couple of years ago from Dario Bressanini, a science communicator, o a YouTube video. Water boils at different temperatures because the boiling point of water changes with the altitude (it’s because of the pressure change). So the water boils at 100°C only by the sea, in the mountain it’s at a lower temperature. But the pasta still cooks because it only needs 80°C to cook. When the pasta is boiling and we turn off the stove for the cooking time and we leave the lid on, the water temperature drops slowly but it doesn’t go under 80°C during the cooking time so the pasta cook properly. If you don’t believe me just DIY at home. By doing this we arrive to save up to 47% of emissions.
The efficiency of boiling water
At home, we have multiple ways of boiling water depending on our appliances and stove. In general, the energy needed to rise 500ml of water from 21°C to 100°C is 0.046 kWh, but moving energy from one place (the source) to another (the water) is not 100% efficient because some energy is lost during the process as heat.
The efficiency is the amount of energy that is delivered to the water as heat divided by the amount of energy the appliance draws in.
- A gas cooktop is 40% efficient. Most of the energy is lost as heat.
- A microwave is 50% efficient. The energy is lost by converting electricity to microwaves.
- An electric stove is about 70% efficient. The energy is lost as heat.
- An electric kettle is 80% efficient. The energy is lost as heat but fewer thanks to insulation.
- An induction stove is about 85% efficient. Little energy is lost with the electromagnetic field.
What I’ve learned
Again we have a communication problem and a practice problem. People cook pasta in this way because it’s part of their culture and don’t believe in a different method. At the same time, pasta industries don’t explain these simple tricks to save energy, it could be written on the packaging. If all Italians would follow these steps, each one would save up to 44.6 kWh, 13.2 kilos of CO2e, and 69 liters of water in a year. Also, the efficiency of the appliances plays an important role, but unfortunately, most Italian houses rely on gas stoves.
