Identifying and detecting the text through OCR (Alerting the saved text (if there or not )through OCR Scan)

I explain a case scenario There will lot of chemical present in Shampoo 's like sulphate , ammonium sulphate etc which are very dangerous. So,In an application we have save those chemicals names as our preference to avoid them when scanned them OCR. 1.)Save those chemical names in your application . 2) Scanned with OCR and it should identify those chemicals and tells us to avoid if those are present.Like Allergens are present or safe 3.)After text has been extracted it should highlight those chemicals.