Simple Paper Based Test To Detect Milk Freshness By IIT-G Researchers
A team of researchers at IIT Guwahati has come up with a simple paper unit that can test the freshness of milk and tell how efficiently it has been Sterilized. Supported with an advanced mobile phone application, the paper unit can help guarantee that milk is devoured before it turns excessively sharp. Milk being broadly expanded consumed food, its security is of prime worry to customers. Despite the fact that purification, freezing, and protection methods are utilized to prevent spoilage, still perishability of milk is as yet a worry.
There is no simple method to know whether milk is fresh or stale and how efficiently it has been sterilized. Tests utilized in dairies and dairy enterprises are tedious and require modern hardware like spectrophotometers. This new paper-based unit created at IIT could make testing milk freshness simple and quick.
A milk enzyme Alkaline Phosphatase is considered to be a milk quality indicator as its presence even after purification indicates the presence of microbes that may not have become inactive with Sterilization. To prepare the detector ordinary filter paper has been used by the researcher. Office punch was used to
cut the filter paper was into small discs and were saturated with chemical probes that would react with ALP. To specifically bind the ALP probes, specific antibodies were used. Combination of ALP and probe turns the white paper disc into a colored one.The leader of the Research Dr. Pranjal Chandra said paper disc was soaked in 4-carboxybenzene diazonium solution and then was treated chemically to expose-COOH groups on the diazonium. On on anti-ALP probe molecules, the -COOH groups are attached to NH2 groups. A drop of milk is poured on the tiny paper disc, and the reaction of ALP in milk with probes takes place, resulting in a change of color.
The smartphone camera captures the color change on paper disc and then the image is processed to obtain corresponding values. The obtained values are compared with standard values stored in the phone. Hence the ALP and the amount of milk in it can also be measured.
Dr. Chandra said they gathered examples from towns and alongside milk spiked with a specific measure of ALP were utilized so as to test the kit. Almost 94% of ALP can be distinguished in a large portion of the cases. Colour is expected just to ALP and not because of obstruction of nutrients, different proteins and minerals in the milk were affirmed by the team. For a subjective examination, no different reader is required. Change in shading demonstrates the nearness of ALP and with the assistance of a cell phone, the correct measure of ALP is resolved.
The kit was prepared by the Researchers by fastening probe disc on a 2 cm square transparent cellulose acetate film. The test is then secured with another cellulose acetic acid derivation film. Colour reaction happens when milk is infused through a small opening in the cover and an advanced mobile phone can be utilized to get the outcomes. All that’s needed is around 15 minutes to identify raw milk from sterilized one.
