Typically you wouldn't use a citation for something like this. You would just put this information in your materials and methods section. E.g.,
Lemonade (John Smith's Lemonade Company, New York) was purchased from Amazon.com and used without further purification. According to the manufacturer product label, the lemonade contained water, lemon juice from concentrate, and high fructose corn syrup and had 120 calories per 8 oz. serving.