What it is and where it comes from
Enzymes speed up changes in food: they set cheese, soften bread, tenderise meat and make syrups. Most are now made by fermentation with fungi or bacteria. Some, like rennet, pepsin, lipase and some phospholipase, can come from animals, including pigs. Papain and bromelain come from papaya and pineapple.
Where you find it
Cheese, bread and baked goods, meat products, juices, syrups and beer.
What to look for on the label
"Enzymes" on a label rarely tells you the source. A halal logo, a vegan label or "suitable for vegetarians" settles it. Otherwise ask the maker.
This is a guide, not a fatwa. Recipes change, so check the label, look for halal certification, and ask your local imam where scholars differ.