Malt syrup is derived from concentrated pre-fermented germinated/malted barley wort (i.e. liquid extracted from mashing process).
Process involves
- Sprout grain, e.g. barley
- Mill
- Mash
- Mash separation
- Wort boiling
- Flavoured with hops
- Concentrate
- Sterilized before storage
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Fig. 1 Flavourful malt syrup (pic from joepastry.com)
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Fig. 2 barley sprouting increases sweetness (pic from thefreshloaf.com)
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Sprouting sweetens grains because of the breakdown of carbohydrate into smaller sugar molecules (nourichedkitchen.com).
Use of malt syrup or extract in beer brewing (beerandbrewing.com).