SCREENING TESTS FOR DETECTION OF ADULTERANTS
Adulterants can be present in food items at ppm/ppb levels , therefore simple visual examination may not always be useful. Reading the label containing the list of ingredients is essential as it will give insight into the quality and nutritional value of the packed food.
As adulterants in food are cheaper than the original product, it benefits the seller but has two main disadvantages for the consumers:
• Financial loss as the product is of low quality
• Such food items are health risks that may even end up being fatal if taken in large quantities. To avoid buying and consuming poor quality food items, screening tests can be carried out to ensure that adulterants are not added, given below are a few tests:…show more content… FOOD GRAINS
To detect the presence of hidden insect infestation in food grains
Dip filter paper in ninhydrin solution, on it put the grain samples and fold the filter paper. Take a hammer and crush the grains, if presence of bluish purplish spots are observed it indicates the presence of hidden insect infestation.
To detect the presence of Ergot infested Bajra as an adulterant Add water to a few grains taken in a beaker, the ergot infested bajra will float in water as they are light in weight
9. DAL AND PULSES
To detect the presence of Metanil Yellow
To a small amount of the dal taken in a test tube add water. Few drops of conc. HCl should be added , quick development of pink hue indicates the presence of metanil yellow dye
To detect the presence of washing powder in ice cream
To a small amount of the ice cream sample ,squeeze small amount of lemon juice; if there is bubbling and froth formation it indicates the presence of washing powder.
11. BLACK PEPPER
To detect the presence of papaya seeds as adulterant
Pour carbon tetrachloride into a beaker containing pepper seeds. It can be observed that pure black pepper seeds settle at the bottom whereas papaya seeds