Filtration is the process that allows you to separate solids from liquids. There are different tools that allows you to do this: from your hands, fabric, mesh, colander, filters.... They all have the same function.
Depending on what solid needs to be separated, you need a different type of filter: in order to stop the solids, you need to use a filter that has holes slightly smaller than the size of the solid that you want to stop. An easy test for this is when squeezing a lemon on your hand: if you keep your fingers together, the liquid and the seeds will remain in your palm. If you separate your fingers slightly, the juice will fall to the glass and the seeds will remain in your palm. If you completely open your hand, juice and seeds will fall, which means that the ''mesh size" (the space between your fingers) was too big to stop the seeds.
Another amazing experiment to explore filtration is making non-dairy milk at home. Today I chose Oat Milk because it is one of the easiest and cheapest, tastes delicious and it only takes 5 minutes!
- Food processor / hand blender / smoothie maker
- 1 cup of porridge oats
- 3 cups of (ideally filtered) water
- 1/4 tsp vanilla extract (optional)
- Pinch of salt
- Muslin cloth / old t-shirt / nut milk bag
- Colander (optional)
- Glass bottle with lid
Get a cup of porridge oats
Put all the ingredients (oats, water, vanilla and salt) in the blender and blend for at least 2 minutes.
Place a colander on top of a big bowl
Now place a piece of muslin / cheese cloth / old t-shirt or a nut milk bag on top of the colander.
After a few minutes, the mix should look very smooth and milky.
Pour the mix over the cloth very slowly, you don't want it to overflow.
Once all the mixture is on the cloth, gather all corners from the top and twist them downwards and start squeezing the ball of oaty mixture. Squeeze until no more milk comes out.
Carefully pour the milk on your clean glass jar or bottle
Keep it in the fridge from 2-4 days.
Remember to shake it before every use. It tends to want to separate but this doesn't mean that is gone bad!
Also, by using this very easy filtration method, you are saving yourself from buying cartons of milk in the supermarket. You can make a bottle of this once a week for very little money without having to throw away a lot of containers.
Remember that everything is washable, no need to dispose anything!