Adventurous knitters may have noticed that several manufacturers now offer yarns made from corn, such as Kollage yarn’s Corntastic or Bernat’s Cot’n Corn (a blend of corn and cotton fibers). But how is it that corn can turn into something soft enough to knit with?
To turn corn into yarn, manufacturers extract a plant sugar called dextrose from the plant fibers. (The image below is of a model of dextrose)
Next, they ferment the corn sugar and distil it, using the same process used to make beer, and then extract the lactic acid that is produced. The lactic acid forms a long chain, or polymer,called PolylacticAcid (PLA) (below)
Once it is spun into yarn, PLA has a texture similar to cotton or even silk, depending on how it is spun, and it is less dense than cotton or wool, so it can be used for lighter weight garments.
Kollage Yarns Corntastic
Since corn is not the only plant that contains dextrose, manufacturers expect that they can use a similar process in the future to make fibers from rice, sugar beets, wheat, or rice.
The polymer used to make yarn can also be used to create plastic-like materials—you may notice corn- or potato-based “plastic” cups, disposable utensils, and the like at your local organic co-op or restaurant. You might also find PLA-based pens, containers, toothbrushes, or almost anything that is typically made of regular plastic.
PLA is biodegradable and requires less carbon to produce, so we should look forward to using these new plant-based products whenever we can!