Since I started making my own wines I've been a bit of a purist when it comes to closures. Like most home winemakers I started out with the cheap agglomerated corks that came with my equipment kit. From there I moved on to the premium #9 corks and started looking at buying solid natural cork. I didn't give much thought to synthetic corks because they were not natural. They weren't the closures that wineries have been trusting for hundreds of years. They weren't "authentic".

One day I volunteered to bottle at a local winery (more about that here). They were using Nomacorcs and were quite happy with them. As I continued to volunteer at this winery I got more and more interested in the closures, how long they last, and what the benefits of using them are.

Then, when my last wine was ready to bottle, I went out and purchased some #9 Nomacorcs to try for myself. The were comparably priced to my beloved #9 natural corks so I took the plunge.
My First Experience with Synthetic Corks
Like natural corks synthetic corks come in a sealed bag and you don't need to worry about soaking or sanitizing the closures. I picked up 30 closures for about $10 US.

When it came time to bottle I pulled one out, inspected it, and proceeded to use my dual lever corker (affiliate link) to insert it into the bottle. One down.

My first impression was that the cork was not as easy to insert as the natural cork because the plunger on the dual lever corker is not as big around as the Nomacorc. This cause the sides of the cork to get caught up in the corker itself and while the center of the cork was perfectly even with the top of the bottle the sides were sticking up. [insert pic here].

Now to be fair I've never had great luck getting even the #9 premium corks to sit quite right either. The difference was that the synthetic corks were still caught up in the corker after inserting the cork so you have to be careful how you pull the corker away from the bottle so you don’t cause it to fall over and potentially break open.

I made some adjustments to the corker and proceeded to finish up the bottling process. After a while I got the feel of inserting the corks and the bottles started to look better.
The Benefits of Synthetic Closures
There are many benefits to using synthetic closures. First, they don't ever dry out. This means that if you pick some up at the local winemaking shop it doesn't matter if they've been on the shelf for six months or a year. They're going to be in perfect condition to use. It also doesn't matter if you keep a stash of synthetics around the house for a couple years.

Natural corks, on the other hand, do dry out. I've purchased “new†bags of corks from wine making supply shops that were already past their prime and when I used them to close off a wine the cork was brittle, came apart in the corker, and left chunks in my wine. Unacceptable.

Second, wine bottled with synthetic corks do not need to be laid on their side... ever. So if you have limited space to store wine this is a great closure to consider.

The real benefit here, at least for me, comes when you've got a wine that throws more sediment after you've bottled it. With a natural cork closure you have to store the bottles on their side. This means that the sediment will collect on the side of the bottle. When you go to pour a bottle with sediment on the sides it gets mixed back up when you stand the bottle up. Then you have to either let it settle for several days before opening it or drink cloudy wine.

With synthetic closures you can stand them up and let the sediment collect on the bottom of the bottle. This makes it much easier to pour the wine without the sediment.

Finally, cork taint not a concern. Not all off flavors and aromas described as cork taint come from cork closures, however, they are the most prevalent culprit.
How long can a wine be aged with a synthetic closure?
The answer to that really isn't known.