The most common ways to cut garlic are to chop, dice or mince. All three words mean essentially the same thing - to cut garlic with a knife into smaller pieces - and their difference simply refers to the size. Chop is usually relatively large, chunky pieces of the garlic clove; dice often times refers to uniform squares roughly ⅛ inch in size; and mince is also uniform squares that are 1/16 inch or smaller in size. From a health perspective, cutting garlic activates the reaction to converts the phytonutrient alliin into allicin. It’s important to note that this reaction can take 5-10 minutes to stabilize so make sure to give your garlic several minutes to settle before you throw it in your stir fry or soup.
Another very common way to prepare garlic is by pushing it through a garlic presser to create a raw garlic puree. A garlic press is a kitchen tool, often metal or plastic, that has a basket (that holds the garlic cloves) flanked on either side by long handles connected a grate with holes and a flat, hard surface. With a firm handshake motion, you squeeze the two handles together crushing the garlic against, and ultimately through, the grate of holes.
From a health perspective, pressing garlic is actually more beneficial than cutting garlic because it more uniformly breaks down the cell walls and triggers a more comprehensive reaction to create allicin. Just make sure to let the garlic sit for a few minutes to allow the enzymatic process stabilize, and make sure to use or store your pressed garlic shortly after preparation because the half life of allicin at room temperature is very quick.
The constant moisture changes from the opening and closing of the door cause the garlic bulb to go moldy more quickly than if the bulb were stored at room temperature. If you have already cut or pressed your garlic, you can store it in an airtight container in the fridge for about a day, but try not to use it as soon as possible.
Most stores sell wire baskets or mesh hangers specifically keep fresh garlic. Do not store fresh bulbs in a sandwich bag or sealed container because the capture moisture will accelerate sprouting and mold.
People often suggest freezing garlic as a way to preserve and that certainly works. It has a lot of the potential for moisture capture and mold mentioned with regards to refrigerators, and freezing is often believed to change the texture and taste. You can peel them, crush them, or dice them and place in an airtight container or bag before putting in the freezer. It’s also likely that the allicin breaks down in the freezer (just more slowly) so try to use the garlic as soon as possible.
Drying garlic is a very effective way of storing garlic that, when done right, can increase the shelf life of garlic substantially without an adverse impact on allicin. Your average low-end food dehydrator is probably fine, just read online to make sure you have the settings right for your unit. The best dry method, at least from the perspective of the health benefits of garlic, is freeze drying or hot bed drying, but these are less accessible outside of commercial factors.