We have just had a very heated discussion of flavored oils on another list
 that I subscribe to. Apparently the risk of botulism is very high because
 the oil sets up the proper enviornment for it to grow. To kill the spore you
 must heat the oil for a period of time just prior to using. If you made it
 for yourself you could control that but if you made it as gifts you cannot.
 Botulism is often fatal so it isn't something you want to fool around with.
 Check with your local extention office, you should have one even in urban
 areas in the USA not sure about how this works in other countries, for
 information. After reading everything I have just read, I have decided to
 make flavored oils for immediate use only. Try vinegars or other acid based
 sauces instead. They are safer.