Updated By: LatestGKGS Desk
IIT-Guwahati develops 'Paper Sensor' to detect freshness of Milk
IIT-Guwahati develops 'Paper Sensor' to detect freshness of Milk: Details, Features, Use, Highlights
Indian Institute of Technology-Guwahati researchers has developed a simple paper kit that can test the freshness of milk and tell how well it has been pasteurized.
It is aided with a smartphone app, the kit can help ensure that milk is consumed before it turns too sour.
Milk being widely consumed food, its safety is of prime concern to consumers. More so because it is highly perishable and prone to the action of enzymes and microorganisms inherently present in it. Although pasteurization, freezing, and preservation using additives are widely used to prevent spoilage, perishability of milk is still a concern.
Working
A milk enzyme, Alkaline Phosphatase or ALP, is considered an indicator of milk quality because its presence even after pasteurization indicates the presence of microbes that may not have been rendered inactive with pasteurization.
Researchers used ordinary filter paper to prepare the detector. The filter paper was cut into small discs and impregnated with chemical probes that preferentially react with ALP. The ‘probes’ used are antibodies that specifically bind to ALP. When ALP comes into contact with the probe, it turns white paper disc into a colored one.
The color change on paper discs is then photographed by a smartphone camera and images processed to obtain corresponding color values. These values are then compared with standard data stored in the phone. Thus not only the presence of ALP could be detected but the amount of it in milk could also be measured.
