I suppose I spend around £45 for OH and me but I could certainly do it for alot less! I grow veg but that's only just starting, but when the boys were little I could make 1/2 lb of minced beef go a long long way!
There are lots of good tips on martins money tips. I find pulses a wonderful way to keep full. I make soup with lentils and split peas, just for a week I would use own brands. Some of them are ok. Extend meat with rice potatoes, eggs. Spanish omellette is good. Shop at about 7 0 clock and the supermarkets reduce the bread and lots of things on their sell by dates, the same if you go to a market near 5 o clock, you can get bags of veg cheaply cos they don't want to cart it away.
Apparently if you look in the skips behind a supermarket they throw away all sorts! But I'm guessing you're not reduced to that yet!