This is all very interesting.
Testing is certainly the way to find the answers.
From the sound of things, I would guess that your culture is going to be quite close to what we wind up with.
If your kraut is turbid and you have cloudiness, then that's a flaw. We want our kraut water to be clear with nothing settled on the bottom. I think they tell me that if you have cloudiness and settling, that comes from yeasts and you do not want yeasts to grow.
Color differences can be very minor, but still perceivable. I just double checked and closely studied some of this year's sauerkraut, and here are some observations:
We have 2 batches, the early one is far more acidic (due to changes in the sugar/starch ratio of the cabbages from early to late time, which was only a few weeks) Neither have any solids precipitated out of the whey at either top or bottom. The liquid is not clouded when I shake them.
The early jars have noticeably greener liquid (these will keep better)
We ferment our sauerkraut in jars under water, covered over and placed in a dark room. We do this in the basement, keeping the temperature under 60 if possible (above 60, especially above 65, is generally when you run into trouble with yeasts)
As for the green globs before rennet, maybe it is nothing. We don't really watch for them or anything, I just always heard that if you see them, it means the culture is working well. Maybe that is an error.
I suppose we will have to subject this to further experimentation. I'm sure you will find something to do with all of that cheese
Note that for the first color change in the whey, the change when stirring the coarsely cut curds before cutting to final size, there is going to be some protein precipitation going on (I think) where we have a white cloudiness resulting from suspended proteins and fats that are absorbed into the curd.
There are two ways to experiment with this.
We can follow the visual targets and watch for pH readings, or we can do the opposite and follow pH targets and observe any visual changes associated with them. If we did this, I would say that we would use pH targets in the ranges generally used for an Emmentaler.
Now with this I would expect that things really aren't going to line up perfectly. We won't have our visual targets fall right on with pH targets. one is probably going to lag behind the other. I am guessing that they work in curves that are not directly correspondent to each other, yet both follow the same general patterns.
The result of this would be that timing of certain tasks will be slightly different if you use one method compared to the other, but that the overall time factor for the cheese as a whole will be pretty much the same. That is to say, the pH when you go into the press will be the same, and the overall timing of the make will be the same.
So if this is the case, we really aren't going by acidity at all, but by unrelated visual cues that happen to fall in a fairly closely related pattern.
We start out with carefully measured amounts of culture and rennet, and we can expect our acidification curve to follow our visual milestones fairly closely. This is a theory that I feel satisfies the current evidence.
In your make of the Alpkäse, how was the finished cheese at the time of pressing?