Fruit Preserves - lemon, salt, sugar?

Hello all!

After a medical consultation and feeling ready for the sad challenge, I’m going to try a partial keto genic diet. It’s sad because I love food and the bounties of carbohydrates. Especially fruit. On my diet, I can have small amounts of carbohydrates. I have a bunch of fruit that I Wonder if I could preserve it in someway to have a little bit at a time. For example I have a lot of fresh apricots. I was looking up recipes for preserving fruit. Is it possible to chop up my apricots into mush, cover and submerge them with lemon juice, and have something that will stay fresh in the fridge for a while? Then I could just use like a spoonful on cheese or something over time.

I found this recipe- https://food52.com/blog/16402-to-lemo...

It seems to be only for citrus fruits. Would that apply to apricots? And can I do it without the salt, fully submerging in lemon juice, as long as I’m keeping in the fridge?

Also curious about kumquats and grapefruit. They are listed in this recipe above as citrus fruits that can be preserved like lemon. Could I cut them up, simmer them and lemon juice, and preserve them in the fridge end without the salt? I just don’t know if I would want salt in every use of them. I Guess it comes down to, if they stay in the fridge, submerged in lemon juice, do they need the salt to avoid bad bacteria?

Another idea, could any of these fruits - apricots, or citrus fruits – be preserved in Greek yogurt? It seems like Greek yogurt often has fruit preserves that stay well in the supermarket small portions at least. Can I mix it with some type of fermented dairy like yogurt, and they will stay good in the fridge for a long period of time? To be able to have a very small amount at a time.

Im excited because I feel like someone will share some really cool science understanding of how the salt in the sugar or the lemon juice and temperature and bacteria all work together. Thank you all chowhoundies.