Evaporation is the process by which a liquid transforms into a gas. It happens when a liquid moves from a vessel or a liquid state to a gaseous state.
In cooking, evaporation is used to remove liquid from a dish, dry out meat, or remove moisture from vegetables and fruits to slow down rot. It’s also used in boiling and frying.
In this post we'll cover:
What is Vaporization?
What is it?
Vaporization is the process of turning liquid molecules into a gaseous state. It can occur at temperatures below the boiling point or at the boiling point.
How does it Work?
When heat is applied to liquid molecules, they convert to a gas. This is called vaporization. There are two types of vaporization: evaporation and boiling.
Evaporation
Evaporation is the transition from liquid to gas that occurs at temperatures below the boiling temperature at a given pressure. This usually occurs on the surface.
Boiling
Boiling is the transition from liquid to gas that occurs at or above the boiling temperature. Boiling occurs under the surface.
Calculating Vaporization
If you boil 100g of water until there is no liquid left, you will get 100g of water vapor.
Evaporation in the Kitchen
What is Evaporation?
Evaporation is the process of liquid turning into a gas. In the kitchen, it’s when you use heat to turn liquid into steam, which can help thicken sauces, reduce balsamic vinegar, and make ghee.
How to Use Evaporation in Cooking
Here’s how to get the most out of evaporation in the kitchen:
- Simmer stews to make ’em thicker and richer
- Cover pots to keep the steam in (like when you’re making rice)
- Uncover pots to let the steam out
- Use a pressure cooker
- Make ghee
- Leave space between food items in the pan so they sear instead of steam
Boiling Away the Watery Blues
Objective
- Evaporation is the process of removing water from liquid food by boiling, to concentrate the food and make it more solid.
- It can also change the colour of food and reduce the water content of a liquid product almost completely.
Field of Application
- Evaporation is used in many food, drink and milk applications, such as milk, starch, derivatives, coffee, fruit juices, vegetables pastes and concentrates, seasonings, sauces, sugar and edible oil.
Description of Techniques, Methods and Equipment
- Evaporators are made up of three functional sections: the heat exchanger, the evaporating section, and the separator.
- Steam, vapour or exhaust gases are usually used as the heating medium.
- The latent heat of condensation is transferred to the liquid food to raise its temperature to boiling point, to evaporate the water.
- Temperature rates are kept low to protect the food from heat damage, usually in the range of 50-100oC.
- The level of total solids in the outlet depends on the composition of the product to be concentrated.
- Evaporation is usually carried out by boiling off water to the air, using immersed electric heaters or multistage shell and tube evaporators, or plate evaporators.
- The simplest form of evaporator consists of an open pan in which the liquid is boiled, with heat supplied through a steam jacket or through coils.
- Plate heat exchangers can also be adapted for use as evaporators.
- Horizontal-tube evaporators have heating tubes arranged in a horizontal bundle immersed in the liquid at the bottom of the cylinder.
- Vertical-tube evaporators use natural circulation of the heated liquid to give good heat transfer.
Alcohol Evaporation During Cooking: The Facts
The Not-So-Great News
Sadly, if you’re trying to watch your alcohol consumption, you’re out of luck. Despite what you may have heard, alcohol doesn’t “cook off” or “bake off” as quickly as you’d hope. In fact, according to the United States Department of Agriculture’s study on alcohol retention, it takes:
- 2 1/2 hours of simmering to remove 94-96% of the alcohol in a wine-based sauce
- 15-40% of the alcohol to cook off in a quick pan sauce with a splash of wine
- 77-78% of the alcohol to remain after a 48-second flambé
The Funnier News
Don’t worry, we’ve got some good news too! Even though alcohol doesn’t evaporate as quickly as we’d like, it’s still fun to cook with. Here are some of our favorite tips for cooking with alcohol:
- If you’re making a wine-based sauce, add a little extra wine – it’ll make it taste better and you won’t have to worry about the alcohol content!
- If you’re making a flambé, make sure to light it up and let it burn for a while – it’ll look cool and you’ll still have some alcohol left in the dish.
- If you’re making a quick pan sauce, add a few extra splashes of wine – it’ll make it taste better and you won’t have to worry about the alcohol content!
Check out the graphic below for more information on how much alcohol might remain in your dish after you cook it!
Does Oil Evaporate or Not?
The Sticky Situation
Have you ever noticed that sticky residue on your vent hood after a fry-up? You might’ve thought that the oil had evaporated and landed there, just like steam. Well, turns out it wasn’t technically evaporation – the residue was just tiny droplets of oil that had splattered or been carried up by hot air or steam.
The Drying Dilemma
You might’ve noticed that certain cooking oils left out for a while dry up – but it ain’t evaporation. It’s a certain category of oils called ‘drying oils’ that can dry out, but it’s not evaporation. It’s a process called oxidation that ‘cures’ the oil and eventually leaves it dry. Who knew you could learn more about this from painters than chefs?
Conclusion
In conclusion, evaporation is an important process in cooking that can be used to create delicious dishes. Remember to keep an eye on the temperature and time when cooking with evaporation, as it can be tricky to get the perfect result. And don’t forget to have fun with it – after all, it’s not rocket SCIENCE! So go ahead and get creative in the kitchen – you never know what tasty treats you’ll come up with!
