What's in the white crystal powder packet you get with cut flowers to keep them fresh?

The floral preservative provides flowers with water and food and contains a disinfectant to prevent bacteria from growing.





The key functions of a fresh flower food are:





- Provides food in the form of sugars to keep the flowers alive. Just like ourselves, flowers use carbohydrates as an energy source.





- Helps lower the pH, which keeps the water/food conducting system in flowers working at maximum efficiency.





The packet of powder that comes with fresh flowers is basically just sugar. There is no evidence that this powder keeps flowers any fresher. It is supposed to kept the bacteria count in the water low.





Also, I heard that instead of the florist floral life extender packet, an aspirin, (not ibuprofen), works just a well. Aspirin seems to lengthen the life of the flowers. Just be sure to snip a bit off the ends of the flowers each day. The stems seal themselves, reducing the water flow to the flowers. What's in the white crystal powder packet you get with cut flowers to keep them fresh?
It's probably Floralife or something similiar. Contains a sugar, an acidifier and a class of compounds called stem unpluggers so the stem will draw the water.