Hi Alison,
I have not seen lupin flour in the UK. Perhaps I haven't been looking, I only ran across mention of it recently. I thought Lupins were poisonous seeds from a well know garden flower, perhaps it is a different species. 11g per 100g is twice as good as the hemp.
The aubergine fritters sound nice, I like fried or grilled aubergine slices layer with fried halloumi cheese slices - nice and high in protein too.
It is possibly the chick pea flour that spikes the blood sugar as it is much higher in carbs I think.
I might try using carbalose low carb flour to make a batter, can you get it, it is very low in carbs and quite like white flour to use?
Lyn