Softening ice cream with guar gum I have several ice cream recipes that I'm generally happy with (texture is good and all). However, I'd like to make a less sweet, less rich version of some of them. 

How much guar gum would I expect to need if I halve the amount of sugar needed, or replaced half the cream with milk, for this example recipe:


560 ml of heavy cream
50 g of unsweetened cocoa powder
150 g of sugar
85 g semisweet/bittersweet chocolate
310 ml whole milk


What if the recipe has no chocolate but several egg yolks?

I know there probably isn't an exact answer, so is there any way I can efficiently test a given amount? In order to directly test it, I'd have to churn a batch, wait for it to freeze, see if it's soft enough, and if it's not, melt and rechurn it, and so on, and I'd much prefer avoiding that.

I saw that some information is contained in the comments on a previous answer, but I'm looking for more detail.
Completely untried idea about efficient testing: You might be able to evenly divide a batch after churning, and stir a different, carefully measured amount of guar gum into each. (I'm not sure if you'd need to pre-dissolve it in a bit of cream). Then you could freeze them all at once, and test for texture. Hopefully your favorite ratio of guar gum will be less than or equal to the average ratio of the batches, so that you can then let it all soften and mix it back together (possibly with additional guar gum), and refreeze. If you're careful to not let it soften too much, you shouldn't have to rechurn it.