Never recycle formula. When it comes to milk and newborns, forget about any recycling efforts. And you may want to forget about being environmental-friendly. The focus at hand, and the most important issue, is your baby’s health.
Milk that sits over a period of time after it has been heated or
used can cause stomach and intestinal discomfort and issues. Also, bacteria from your baby’s mouth enters the milk and this bacteria sits and settles in the milk which can be harmful to your baby. This is why it’s important to avoid making too much formula.
Don’t overdo it and end up with leftover milk. Prepare the right amount the first time so you won’t waste formula and money. If you do have milk left over, make sure it doesn’t sit long before it’s used again. In other words, you can reuse it only if it’s in the same feeding setting, but not hours later.