Hiya Lou! You don't say what type of milk you're looking for, or how old your son is, but Spar have rice and soya milk, and Hiperdino have goats milk.

HTH
Edited: sorry, you asked for the biggest supermarket! I know that Eurospar on the outskirts of Arrecife have the milks!

Thanks that´s great.....he needs rice or chufa milk....he´s allergic to soya.
Right off supermarket hunting we go....thanks again.....Lou x

Lou, chufa milk is sold as Horchata in Lanzarote, in small bottles in the supermarkets, and can be got in most spanish bars

Hope you find what you're looking for

There's a good Netto supermarket just across the road from the main entrance of Los Zocos - they might have what you're looking for.

Hi everyone...thanks for all your suggestions.
We had a nosy round locally....with no luck. Spoke to the Chef in the carvery in El Boulevard, who suggested the Eurospar in Arrecife.
They sell a reasonable range of stuff....we managed to get almond milk and oat milk in there. Also in the same shopping centre there is a health food shop where they sell all the differnet milks including rice milk.....for anyone woth coeliac or wheat allergies they also had a lot of the Schar range in there.

(after all the hunting....he wouldn't drink any of them....didn't like them!!!)

Thanks again
Lou x