Congener by definition means this- minor compounds other than ethanol that occur naturally in alcohol beverages as a result of the distilling or fermenting processes. If you are reading my blog, you know a little bit about alcohol. What you may not know is that pure alcohol has no odor.  When it is consumed, such as high end Vodka, it won't have an odor coming off of your breath. I had a client with a .259 BAC with no odor of alcohol.  Luckily, we won that that case and one of the primary reasons was the lack of odor during the on-scene investigation.  What causes the odor of alcohol?  Well, if you know anything about beer, you are aware that it is made from hops that ferment and flavor the beer.  There was a private distillery that I walked past to get to court many years ago and they kept the hops outside in big buckets. You could smell the odor of sour hops from a far distance. So, you get my point.  Most alcohol is flavored with a substance during the fermentation process.  Oddly enough, that flavoring is what the officer smells when they speak with you during a DUI investigation. One of the most important on-scene tools an officer uses during a DUI investigation is the nose and sense of smell. So, what should you do if you've had a few drinks with the guys and decide to drive home afterwards?  This also ties into the million dollar question I posted a few days ago. I still need to improve my Google rating by blogging more. So, I will get to that million dollar answer shortly.  Stand by.