Adulteration of olive oil with lower-grade oils was a known issue. Some products labeled as "extra virgin olive oil" may not meet the quality standards claimed on the label.
Fake honey may contain added sugars or syrups. Some honey products on the market have been found to lack the beneficial properties associated with pure honey.
Adulteration of milk with water or other substances has been a longstanding issue in some regions. Additionally, counterfeit dairy products with lower nutritional value might be sold as genuine.
Mislabeling of fish species is a common problem. Some sellers may substitute cheaper fish for more expensive varieties, and there have been reports of farmed fish being sold as wild-caught.
Ground spices are susceptible to adulteration with fillers or cheaper substitutes. For example, saffron might be mixed with other substances to increase weight.
Ground coffee might be adulterated with substances like chicory or corn to stretch the product. There have also been concerns about counterfeit coffee beans being sold.
Some fruit juices may not be 100% pure, with added sugars, water, or artificial flavors. Counterfeit versions of popular beverages have also been reported.
Tea leaves may be adulterated with fillers or other types of leaves to increase volume. Some teas may also be contaminated with pesticides or other harmful substances.