"Garlic in its natural state is not a good source of allicin. However, when the garlic bulb is cut or bruised in some manner, enzymes in the garlic begin to react and create the compound. This compound is also deactivated by acidic environments like the stomach, and is damaged by heat. Thus, cooking with crushed or minced garlic will not allow the user to receive any health benefits of these types from the allicin content of the cooked garlic. It is also not very shelf-stable, even in liquid form, and short shelf-life."

"the alliin and allinase that are stored apart from each other in the clove mix together and form the allicin, which is what causes garlic to smell and taste as it does. Allicin is a volatile substance that will break down on its own in a few hours and form several different sulphuric compounds. Heating allicin will cause it to break down much faster. The more allicin breaks down, the less of the smell and taste are present. Therein lies the second of the secrets to using garlic."

Therefore by heating the garlic, the alteration of flavor is actually the key component allicin being destroyed. Since the smell and taste of garlic come directly from allicin, I believe it is safe to say the less it tastes like fresh garlic, the less allicin it has, thus the less beneficial it is. Allicin is extremely unstable and sensitive, it has a short shelf life and is easily destroyed by heat. So to receive the full benefits of your garlic, be sure to crush thourougly allowing the enzymes time to produce allicin before consuming.

"When cooking with garlic, it is advisable to add the crushed or chopped garlic to the food right before it is done cooking. This will uphold the potency of allicin as long as possible before consumption, and helps to prevent the heat from destroying the beneficial effects. Microwaving garlic will completely kill the allicin and its therapeutic effects.

The more you cut the garlic, the more of the allicin is formed and the stronger the flavor. If you cut a clove into 8 slices, it will have more flavor than if you cut it into only 4 slices. If you dice the clove into many small cubes, it will release even more flavor and if you crush it, you will release the most flavor."

This is why i've heard of chefs cutting the garlic with razor blades to maximize the flavor derived from each clove.

"Allicin acts as an antibiotic, antiviral, antifungal and anticancer substance. It combats Candida, boosts the immune system and alleviates skin problems. It also fights against cold and flu, lowers cholesterol and acts as a natural bug repellent. It has been said that garlic is good for your heart as well."

The allicin is created by a reaction of alliin and allinaise when they are mixed together, so letting them react with eachother after crushing/slicing will increase the ammount of allicin. Dried/powdered garlic will retain NONE of the benefits of fresh garlic. FRESH garlic is key here as the ingredient we are after is actually created right before we consume it.

"try munching on parsley to rid yourself of garlic breath"

Allicin has been succesfully isolated though, and used in the treatment of various infections. So it is possible to extract the healing properties of garlic. In regards to fresh garlic though, no heat, crush thourougly. It is antibacterial, anti-viral, antifungal, and contains many other benefits.

Here is a picture of some garlic cloves, I ate the smaller one. I do not dare to eat the big ones whole; I usually split them up. Causes quite a bit of pain in my stomach. http://i.imgur.com/V16Xp.jpg

SOURCES:

http://en.wikipedia.org/wiki/Allicin

http://www.wisegeek.com/what-is-allicin.htm

http://www.gourmetgarlicgardens.com/cooking.htm

http://www.ehow.com/list_5782110_allicin-garlic-side-effects.html#ixzz1pKbY8WZN"

http://homecooking.about.com/od/cookingfaqs/f/faqgarlicsmell.htm