Wheat beers, such as the German beer style hefeweizen, are well known to have a pronounced banana flavor. The aroma compound responsible for this banana flavor is isoamyl acetate.
The odor detection threshold of an aroma compound is the lowest concentration that can be perceived by the human sense of smell. The odor detection threshold for isoamyl acetate in beer follows a normal distribution with a mean of 2.33 mg/L and a standard deviation of 0.69 mg/L.
The beer company Megabrew is developing a new light malt liquor, Taipan Light, that uses wheat in its formulation. They do not want Taipan Light to have a banana flavor. Megabrew has determined that if less than 10% of people taste banana in a beer, the beer is not considered to have a banana flavor.
How low does the concentration of isoamyl acetate in Taipan Light have to be to ensure that less than 10% of people taste the banana flavor?