Most of us are used to store food in the fridge randomly... The first item out of the bag goes first in the fridge. Tomatoes in the lower compartment, potatoes in the door, cheese above lettuce and we just assume that it will have no impact.
Do you also believe that the fridge is just a cold box and nothing else? Then this blog is for you.
Even though very few of us know it, the temperature of the fridge is not consistent in all its compartments. As a matter of fact, it was divided in four different parts so that we could store our food as best as possible. This means that the pie I started to enjoy last night and the lettuce do not require the same amount of humidity, nor the same temperature. Hence, here are a few rules to follow and how to stick to them to store your food:
The different temperatures of the fridge
The north pole of the fridge, unlike what we may think, is not located on top of it, but above what we could name “the vegetables’ compartment”. Over there, the temperature is 2ºC and this is where the food that needs the coldest environment should be stored, such as meat, fish and drinks. If, as I did before doing my research, you were storing lettuce over there, it would be better to move it elsewhere not to ruin it.
The second coldest compartment is the one in the middle, which has a temperature of 5ºC. This spot is ideal for dairy, tofu, cream-based desserts, etc. Furthermore, this is where you should store open cans, such as the ones containing olives, or spreads.
All the way up is the superior compartment dedicated to pre-made food, including the meals prepared following the “batch cooking” trend. The temperature is 8ºC in this compartment, which is also the widest one. If the fruits and veggies’ compartment is not big enough, this is where they should be moved.
To finish with, the inferior compartment with an overall temperature of 10ºC. It is the perfect spot to store all kinds of fruits and vegetables. Additionally, it often is the most humid part of the fridge, which is essential to maintain the quality of fruits and vegetables. If you have a newfangled fridge, you can also control the level of humidity.
The ideal general temperature of the fridge:
Like everything in life, the number one rule is not to go extreme. If you push the temperature to its coldest, it will be too low for most foods, hence fruits and veggies will freeze or go bad and the remaining foods will lose their flavour. What’s more, it will overwhelm the freezer’s compressor for no reason. If you leave the temperature to its warmest, loads of foods might go bad, such as dairy and meat. Therefore, the solution is to opt for a good balance between 3 and 5 depending on the fridge you own. If you have a newfangled fridge, you can control even more parameters. In that case, it is better to follow the manufacturer’s instructions.
A few tips to maintain the perfect temperature:
- Do not overload your fridge.
- Do not store food that is still warm inside your fridge.
- Never let the door open. Make a decision before opening the door and avoid to leave it open while you are making your mind.
Up to now, everything is fine. But the true magic resides in the manner you package your food before putting it in the fridge and in the food that should never get into it.
How to better preserve food?
Fruits and veggies, unlike other foods, keep “living” once they leave the ground, a crop or a tree, which implies that they need to keep breathing. During this aging process, nutrients degrade, as well as flavour and the amount of water they have. That is why it is important to reduce the respiration phase so that quality remains. Furthermore, fruits and vegetables do not all breathe at the same pace. In some cases, such as the one of broccoli, vegetables limit the oxygen amount they expose themselves to (because of plastic bags) so that their respiration slows down. This can also happen in your fridge: if you use hermetic containers (to avoid single-use plastic) or reusable silicon containers. High temperatures also accelerate the respiration process; that is why some foods must be kept in cold compartments.
Another factor closely tied to fruits and vegetables’ preservation is the hormonal activity regulated by ethylene. If you have never heard of it, it is a naturally-occurring gas produced by fruits and vegetables. Its role is to regulate their growth and aging process.
However, this gas is not always created the same way. It can be divided in two main categories; climatic and non-climatic.
Climatic gases keep evolving are being separated from the crop. In the end, they have a higher ethylene production. Non-climatic gases stop evolving once they are separated from the crop.
This gas can be an ally as well as a rival; it all depends on the way we use use it. Here is how.
Ethylene as an ally: Learn how to control it
Fruits and veggies that do not produce ethylene (because they stop the aging process) can be affected by the ethylene produced by others, which means you can control the aging process. This is good news when you want to eat an avocado which is not ripe yet. All you have to do in to put it alongside bananas at warm temperature. Moreover, by controlling this process, you can keep gas-producing foods away from non-gas-producing foods in order to lower the pace of the aging process.
Who is who?
Climatic fruits and vegetables: Mangos, apricots, avocados, bananas, kiwis, peaches, papaya, cantaloupe, tomatoes, apples, figs, plums, nectarines, etc.
Non-climatic fruits and vegetables: strawberries, grape, raspberries, lemons, oranges, pineapple, grapefruits, chilli peppers, pomegranate, olives, cherries, cucumbers, aubergines and pumpkins.
You can also follow these tips to preserve your food for longer:
- Lettuce and other green leaves: Wash it and disinfect it, dry it and put it in a closed box, interspersed with absorbent paper. Or, f you prefer not to use paper, (which is better for the environment), use a slightly humidified cloth. Put it on the table and roll the green leaves in it, like a spring roll.
- Carrots, aromatic herbs and celery: You can put them vertically in a glass jar with water (the same way you would arrange flowers) and put them in the fridge or not. If you pick this option, you should change the water regularly to prevent the food from going bad.
- Avocados: Once ripe, you can stop their aging process by putting them in the fridge (this will only work for a few days). Once cut open, it is advised not to peel them, as if you were going to open them again.
To keep out of your fridge
These foods should never pay a visit to your fridge:
- Tomatoes: This piece of fruit keeps aging once gathered. Hence, if you put it in the fridge, this process will be stopped, which will alter its consistency and flavour.
- Bananas: Contact with cold turns bananas brown because of an enzyme activated by low temperatures.
- Cucumbers: They are very sensitive to cold, that is why it is better to keep them outside once you start consuming them to prevent them from turning white and sour.
- Potatoes: They have nothing to do in the fridge, as coldness turns the starch they contain into sugar, which gives them a sweet flavour and turns them black. Be careful as this does not only apply to raw potatoes. As a matter of fact, chips put in the fridge can provoke the creation of acrylamide, a potentially dangerous substance.
- Honey: This very sweet food will crystallize if you put it in the fridge. The best solution is to put it in a dry and hermetically closed container.
- Garlic and onions: In the fridge, they will turn white and become rubbery. They enjoy more of a dry and dark environment and must be kept away from potatoes which would accelerate their aging process.
- Avocados: This food is one of the scariest ones because of its aging process. Once separated from its crop, the process starts, and you need to be patient and careful if you wish to obtain the perfect avocado. If you have already bought it ripe, putting it in the fridge can be a good idea as it will stop the aging process. Otherwise, you can store it next to potatoes to accelerate the aging process.
Here we are, you now have all the tools necessary to control what goes on in your fridge.
Always remember those simples principles: Try to plan your purchases not to buy food in excess, emptry your fridge as much as possible before running errands, freeze everything that could go bad in order not to waste food, make broth with fruits and veggies’ leftovers and eat everything that is good.
Do you have other tips? Share them in the comment section!
1. https://www.hortalizas.com/cultivos/manejo-de-etileno-de-frutas-y-hortalizas-durante-el-almacenaje-poscosecha/, Erandy Rizo (2014), Manejo de etileno de frutas y hortalizas durante el almacenaje poscosecha, Revista Hortalizas.
2. Ethylene effects, Mikal E. Saltveit USDA, ARS Agriculture Handbook N. 66
3. Respiratory metabolism, Mikal E. Saltveit USDA, ARS Agriculture Handbook N. 66
4. Ethylene and fruit ripening C. S. barry and J. J. Giovannoni, J. Plant Growth Regul. 26, 143 (2007)