I recommend you use a glass fliltration system, you can get easily in aliexpress. You can get a hand pump or an electrict pump, i had both and i really have to say that the electric one is worth the money. Respect sterilization i clean them first with antibacterial soap and hot water, later i rinse it well with IPA and then i cover the top of the neckd with aluminium paper and put them upside down in the oven at 200C for about 30 min. After those 30min i turn off the oven an open a bit the door, so they can get in normal temp by themselves. If you don't do this step can be the case that they get humit inside for the strong change of temp. One time they are at normal temp, you can use them. After the use them clean them again with hot water and antibacterisl soap and then clean them again with super green, ove cleaner or degreaser in order to really clean it well. Otherwise when you bake them again in the oven they will start to get brown because the little rest of the oil that the soap can't clean.
I hope you understand now better the process of sterelization
Good luck!!
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