Malt is great for increasing breast milk perhaps that's what it is. I drink a malt-based drink (Ovaltine) which I love (regardless of that fact) but also fenchel and anise teas are very good. Not only do they increase your supply (drink 3-4 cups a day) but help when the baby has gas.
I drank non-alcoholic beer when breastfeeding. Don't drink any alcohol. But the non-alcoholic beer and a kind of tea called "Mother's Milk" tea helped me.
It may or may not help with the production of milk, I don't know. But I definitely know that having alcohol in your milk will NOT help your baby - especially a premie! Drinking lots of fluids, getting rest, decreasing your stress, and nursing often for longer periods of time will all help your milk supply - without introducing harmful chemicals to your daughter. Find your local chapter of LaLeche League or call your local hospital and ask for a lactation consultant - they will be able to help you safely.