Leah Putnam’s Juicing Essentials
This type of juicer uses a fast spinning grater to shred and breakdown the fruits and veggies and then strains the juice to separate the fiber from the liquid. This juicer is typically easy to use, quick to clean and has the lowest price tag. The draw back is that method used to grate and spin the fruits and vegetables causes the juice to oxidize (you usually end up with a fair amount of foam) and the enzymes to start denature quicker. This means you will want to consume this juice within 15 - 20 mins.
The next step up in quality and of course price, has a slow screw shaped gear that chews up the cell membrane of the veggies to release the nutrients and then squeezes the juice through a mesh screen. With this type of juicer you will usually end up with more juice, more nutrients intact, less foam, and a longer fridge life of about a day or more.
Twin Gear Juicer
Up from there you will find the Twin Gear Juicer. This type of juicer works at even lower speeds. It chews up the veggies and fruit between two gears that squeeze out the juice and leaves a very dry pulp. The end result will be more juice, more nutrients intact, less foam, and a longer shelf life. You can store your juice for up to 72 hrs in fridge. The Green Star is a twin gear juicer and is the one I use.