Depends on the sourceDepends on the source. Most glycine is made synthetically and is halal, but it can be made from gelatin, which may be from pork.
Depends on the source means it can be made from plants, microbes or minerals, or from animals, including pigs. From plants, microbes or a halal-slaughtered animal it is halal; from pigs it is not. The label often does not say which, so look for a halal logo, a vegan label or a note on the source, or ask the maker.
What it is and where it comes from
Glycine is the simplest amino acid. Almost all glycine for food is made chemically from simple raw materials. It can also be made by breaking down gelatin, and then the gelatin source matters.
Where you find it
Flavourings, sweeteners, drinks, sauces and supplements.
What to look for on the label
Look for a halal logo or a vegan label, or ask the maker whether the glycine is synthetic.
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.
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