Portion-control packaging is nothing new. Snacks and other foods have been helping people measure out servings with single-portion-sized packs for some time now. But Sainsbury’s has turned the concept on its head with the cartons for its by Sainsbury juice line. Rather than controlling portions, four see-through windows on the side of the carton are actually encouraging portions-helping consumers measure out one of their “five a day” servings of fruit. The windows also have the added benefit of showcasing the color of the juice. Is there an opportunity to readapt a packaging concept for your brand?