How corn flakes are made

Mill the grits

Corn is milled into coarse grits, each of which will become roughly one flake. Grits are the normal starting point for the traditional cook-and-flake route.

Cook with malt and sugar

The grits cook with enough water, sugar, malt syrup and salt to end up soft and pliable. One General Foods patent example reaches 24% moisture at this stage.

about 24% moisture

Dry the cooked grits

Vertical dryers pull water out of the sticky cooked grits. Faster plants can use a multi-pass traveling screen dryer with controlled humidity and airflow instead, which takes about 30 minutes.

Temper in bins

The dried grits rest in tempering bins, about 7 hours in the patent's example, so that moisture evens out through each particle. They come out at about 14%.

about 14% moisture

Soften with humid heat

A short pass through humid air warms the grits to around 152 °F. Moisture stays about the same, but the grit turns plastic enough to flatten instead of crumble.

Squeeze between rolls

Warm grits drop from a feed hopper into the nip of the flaking rolls and come out as thin, soft flakes.

Toast until blistered

A toasting oven at 300 to 400 °F browns the flakes and raises blisters on their surface. Moisture drops to about 2%, which gives the crunch.

300-400 °F

Coat and pack

Toasted flakes can be eaten as they are or coated with a sugar layer carrying vitamins and minerals, then bagged and boxed.