This is my experience...
Pasteurisation, means it is heat treated.. so your pectic haze may well be enhanced depending on the apple varietals. Heating apple juice makes a pectic haze more difficult to shift, in its entirety.
Think milk. It's done to kill bacteria.
Ascorbic acid is an antioxidant, a preservative and promotes yeast growth....it's used to prevent the juice browning. Browning creates two issues, taste changes and colour changes. In a wine a deeper colour may be fine, however if that comes with off flavours, you need to balance your colour need, against bad overtones in the finished wine.
Citric acid... is different.. it does most of the job that ascorbic does with stopping discolouration, however, not as well and it is mainly a flavour enhancer. If all you have is citric acid, use it. Thing is, you have to keep as much light from your must and finished stored wines as possible, they will degrade quicker.
I make a lot of apple cider and I add citric acid as soon as I remove the apple juice from the juicer, it goes directly into the primary and that covered primary is fully primed with citric acid from the get go, til I finish filling to 6 gallons.
No browning means a beautifully clear cider in the finished product.
If you have purchased heat treated apple juice, just finish the fermentation process and add the pectic enzyme once it is done. Pectic enzyme does not work well in the presence of an active yeast fermentation. It will clear your wine after ferment is complete. Once clear move to fining ( if needed) then sulphite/stabilise and bottle.
Allie
