yes as a snack in place of rusks.
You can also use rice crumbs and put on outside of potato wedges, bake then for a yummy finger food snack.
As for allergy symptoms- immediate string reactions after the food is ingested: - the main one is rashes/execma, the othe is profuse vomiting/spitting up, crying/screaming with sore tummy even though the two last ones can be intolerance too, poor weight gain due to damaged gut.
Ds2's symptoms mainly are reflux related (intolerance symptoms can be niggling and get worse over time as they are continually exposed) - rate of relfuxing, hiccups, stiffness, relfxuing up behind his nose - so that he needs to rub his nose and his eyes water, sore tummy with grunting, lack of appetitie wanting to take small feeds.