Lupin has been declared a Top 14 allergen in Europe, so must be labelled on any food products bought and consumed. There are two types of lupins identified by the World Health Organisation (WHO) as having identified allergens.
White lupin is commonly grown in Mediterranean countries and is a legume which can be ground into a flour and used in baked products. The key allergen in white lupin is Lup a 5 which is a plant profilin protein.
The other lupin identified by WHO is narrow leaved lupin, more widely distributed across Europe, Asia, North America, Africa and Australia. This plant is different in that it contains Lup an 1, a 7S seed storage protein and Lup an 3, which is a lipid transfer protein (LTP).
I have put together some more comprehensive resources at http://www.allergyresources.co.uk/Lupin.php
The allergy resources page for lupin covers the key allergens, which allergic syndromes are linked to this allergy and other foods which are commonly cross reactive with lupin.
There is also regularly updated links to useful websites specifically for lupin allergies and the latest research papers on the topic.
If you have multiple allergies and are interested in how they are linked or want to find out more about food allergies outside the usual top 14 then you can follow me on Facebook or Twitter, where I share a food allergy card every day of the week.