Secondary Fermentation Question

[GB2014]

Hello, I am not sure about secondary or malolactic fermentation and I have a couple of DJs of apple juice which have almost finished fermenting so if anyone could clear this up for me that would be helpful.

Do all drinks undergo secondary fermentation or only wines, or only some fruit bases?
Is secondary fermentation desirable?
If I metabisulphited my juice and then added yeast, will it occur?
Should I move the juice to a warmer place, or siphon it into a new DJ, leaving behind the residue, or both (or neither)?

 

[Chippy_Tea]

Is the apple juice you refer to bought juice or did you use your own apples?

 

[GB2014]

own

1234567

 

[GB2014]

I have ascertained that secondary fermentation is fermentation where the yeast consumes byproducts/waste products of primary fermentation, or other, less desirable substances present, rather than the sugar. It starts as soon as primary fermentation starts and continues for some time after it finishes and is much slower.

Once primary fermentation is finished you should rack your drink to get rid of the lees, all that cr*p at the bottom, which is not only unpleasant to have in your drink but adds unpleasant tastes, move it to a cooler place and then possibly some secondary fermentation and some other chemical processes take place and some more particles drop out and the taste improves with time. When your cider tastes nice you can rack it again and bottle/drink.

 

[tonyhibbett]

Sulphite prevents malolactic fermentation.

 

[GB2014]

Aha, malolactic fermentation is one process within secondary fermentation, where malic acid, with a sharp taste, is changed to lactic acid, with a much smoother taste.

Is there any way to make it happen once you have added metabisulphite?