You may be able to build up a database from these questionnaires that gives you enough information to then complete some/all of any new ones you then receive.
However, as you're in the UK, where the food sector is absolutely insane, lots of customers will insist that you have to complete their specific format of questionnaire.
Equally you'll probably find that elsewhere in the world (even just over the channel in mainland Europe) there are suppliers who will outright refuse to complete these or will only complete parts of them, much to the dismay of the UK market.
The approach here is therefore partly going to be determined by the position your business chooses to take - if you believe you have enough information then you could make your own "standard" document for each product / group of products, and advise your customers that this is what you are able/willing to provide for each ingredient.
This will upset some of the customers (even if it's not really justifiable for it to do so), so you will want to get your salespeople to support the approach!