NRCM scientists detected 5% mixing of offal meat in burgers, nuggets and kheema in their research. In the West, any burger or nugget label mentions each organ of the chicken or lamb used, but such categorisation is not done in India.
NRCM scientists, led by M R Vishnuraj, developed a microRNA technology to differentiate the meat. “DNA-based methods will not be able to detect this type of intra-species adulteration. Organ-specific microRNAs can be detected to find out what organ the burger or nugget or kheema is mixed with,” Vishuraj explained.
The technique will help us identify meat from different organs used in a burger or cutlet. Authorities now should make it mandatory for burger-selling companies to mention the organs they use to prepare the patties. The technology can be used to catch those who don’t practice what they declare. The paying public has a right to know what it is eating.
Normally, food labelling requirements of a regulating authority want manufacturers and restaurants to indicate the actual ingredients used in processed meat products. “However, skeletal meat is often replaced by cheaper offal meat to maximise the revenues from processed meats. This leads to food adulteration,” Vishnuraj pointed out.
Since DNA-based analytical methods were of little use as all the tissues have the same DNA sequence, NRCM used tissue-specific miRNA biomarkers to detect the presence of offal (liver, heart and gizzard) in skeletal meat of chicken, the scientist said. MicroRNA is the name of a family of molecules that helps cells control the kinds and amounts of proteins they make.
The scientists performed deep sequencing of chicken microRNAs from liver, heart, gizzard, muscle and blood for each sample of the minced meat. “Unique and differentially expressed miRNAs were evaluated. Specific miRNAs having differential expression in each tissue studied were selected as candidate markers. These candidate biomarkers were later validated in tissues. We could detect 5% mixing of offal meat in any given sample,” said Vishnuraj.
The research was published in the Journal of Food Science and Technology.