Sea salt Topcorn is freshly popped butterfly popcorn that's lightly tossed in natural sea salt, it is a classic flavour that never goes out of style. With all natural ingredients & 108 calories per bag, it is the ultimate alternative to crisps. Delicious, low calorie healthy popcorn. Our man with the pan, Julian Metcalfe, started the craze, popping corn for his ground-breaking Pret A Manger & itsu shops years ago. He's still popping with gusto today.