To be quite fair, anything could be an allergen/intolerance. Non common ones could be; - Potatoes - Tomatos - Yeast (intolernace) - Beans & pulses (usually linked with more common allergens such as milk) - Peppers - Strawberry's/Raspberry's I tend to treat everything new as a potential allergen/intolerance & give it 2 - 3 days of trying my daughter on first tastes with something before moving on to something else.
Following
https://www.srnutrition.co.uk/2019/11/introducing-allergens-during-weaning/
There's a list on the nhs website
Th app solid starts is really good x