I am trying to make decently smooth and scoopable ice cream. I don't have any thickening agent at the moment and I also don't have an ice cream machine, so to make a decently viscous blend that isn't more fat or sugary than a Ben & Jerry's I mixed whipped cream with a base of (boiled and later cooled-down) milk, sugar and 15% fat sour cream. I also combined 1 teaspoon of soy lecithin into this ~800 gram solution.
The fat and sugar concentration should have been close to 20% percent (it was too sweet for me, perhaps due to the taste profile of the dissolved sugar); it was close to being scoopable but still required 10-15 minutes thawing and wasn't as smooth as you'd like.
The reading I made about the different thickening agents often said they have somewhat different properties and are best combined to reach a balanced chemical effect. It was sometimes said locust bean gum might perform a bit better then guar gum, but a main point was that all of these thickeners cause the milk proteins to separate when the ice cream starts melting, and that it is advised to combine guar gum (for example) with carrageenan to mitigate this effect.
I can see in the Ben & Jerry's ingredient list that it indeed contains lecithin (both from the eggs and from soy lecithin), guar gum and carrageenan. But I read some people's claims they made great ice cream adding only inverted sugar and guar gum, and it was also claimed somewhere that "food grade carrageenan" is often adulterated and is considered a possible carcinogen and a cause of gastrointestinal illness.
So to summarize, is it still possible to make descent ice cream using only whipped cream, milk and sugar thickened with guar gum and soy lecithin, or is the mentioned protein-separation effect that detrimental?
Thanks in advance.