Do you find yourself with an opened white wine in your fridge? Keeping the wine fresh is really easy. With a small, inexpensive device your opened wine will essentially taste the same for close to a week. If you just recork it; it will become a completely different beverage overnight.
The point in preserving wine is to pull enough air out of the bottle to keep the wine from oxidizing (e.g., changing). If you pull out too much air, you risk pulling out flavor.
I keep it simple and use a VacuVin Vacuum Wine Saver. With practice, you’ll “feel” the air in the bottle change and you’ll instinctively know when to stop pumping. Tip: approach it with gentleness not vigor.