Mud, you got to try the knock them in a bucket or scrape across a screen. It goes really fast and gets rid of almost all of the stems. Float off the unripe ones and it just gets better. Its not worth risking adding copper when its so easy to pick them and sort them this way now. When we do the pressing I still freeze the berries and then thaw them overnight, crush them in a grape crusher with the rollers set really close and add pectinase and KMeta overnight. Next day press, either just by hand wringing them out in a strainer bag or putting them in a winepress. This 100% juice is strong stuff, I have a batch right now from 8 gallons of fresh berries we picked by the knock in the bucket or scraped on a screen. I might have to do the cassienate treatment to knock down some of the tannins. Also steaming 50 pounds of berries will give you about 5 gallons of juice, this stuff is also really good and doesnt take very long to age since a lot of the tannins are not carried through the steaming. Crackedcork