Sensing approaches toward detection of urea adulteration in milk

Healthy food has a significant impact on human health. Food Adulteration is one of the main concerns of the food industry due to its risks to public health, and accurate detection of food adulteration is essential for food quality monitoring. As a complete food, with wide consumption worldwide, milk is one of the most reported foods that has been adulterated. Urea is one of the most common milk adulterants and is utilized to show higher protein content in milk misleadingly. Urea ingestion could be harmful to the kidney and gastrointestinal system. There are some conventional methods for monitoring urea levels in milk but the advantages of sensors compared to the conventional detection methods, have made them promising tools for the convenient, rapid, and efficient detection of food adulterants. A wide variety of biosensing approaches for the detection of urea adulteration in milk have been developed in recent years. In this review, the classification of biosensors has been discussed based on enzymatic and non-enzymatic approaches and subdivision based on their transduction signal systems for the detection of urea analyte.