Is there any method to determine the shelflife of a product within 1 or 2 weeks?
yes there is.
search for accelerated shelf life determination.
Is based on product ,it is perishable or kind of semi or non perishable, there will be you count of micro after some days whenever you want (factors are affect on product like water activity, moisture, humidity,air).
Its a kind of flour mixture. So how to determine shelflife using that kind of parameters ?
Flour based products had varied shelf life depending upon producr type, processing , product moisture content, , storage conditions, packaging,…
You should be specific .
If permitted details of recipes and procedures can help in predicting its effective shelf life.