3 Things You Need to Know About Bioproducts

To Starch Off

When considering bioproducts it can be difficult to think of how plants can be turned into products beyond food. What is really crazy is just how many different products are created from a simple starchy plant we all know and love, corn! Yes, corn has numerous uses that go far beyond feeding cattle or as a side dish for family dinners. There are, of course, processes such as milling or fermentation that the corn must go through in order to be used in these different outlets. From this article you will learn about the milling process, fermentation, and what can be done with the leftover parts (stover) of the corn plant.

Milling it over.

The first step in making the corn able to be used in bioproducts or as biofuels is milling. The purpose of milling is to remove the starch from the rest of the corn as it is what can be used in the bioproducts. There are 2 main types of milling: dry and wet milling. The vast majority of milling done in the US is dry milling which accounts for 80% (Lesson 18). In dry milling the corn is ground up into really small pieces, that is really all there is to it. After its ground it is mixed with water and various enzymes to separate out the starch and obtain the glucose needed to create the bioproducts. Wet milling is however more complicated and more expensive, thus the reason it is used much less. The advantage to wet milling is that it separates out all the parts of the corn kernel which allows for more products to be produced from the kernels rather than just glucose. Understanding how exactly it works is not all that important, but understanding that it does have its own benefits in comparison to dry is good to keep in mind.

Ferment me not!

When people normally think of fermentation beer comes to mind far before plastic or ethanol, but in reality fermentation of the glucose obtained from the corn is what creates the ethanol. Fermentation is a natural process by which yeast and other microorganisms “digest” glucose or other sugars and the output from this is ethanol and carbon dioxide (Article by MN editors). The ethanol produced from this process is then distilled which makes it usable as gasoline. Ethanol can be used in other ways such as creating plastic.

What to do with the leftstovers?

Once we take the corn from the stalk there is still a large amount of plant left and we don't want it to go to waste. There are 3 thermochemical conversion processes by which this biomass can go through. The first is combustion, which is simply just burning of the stover in order to create energy. The next process is gasification where under high heat and low oxygen the biomass is turned into a synthetic gas (syngas) which can be used for various purposes (Lesson 21). The last of the 3 is pyrolysis which is the breakdown of the biomass in a heated environment with no oxygen present (Lesson 21). The process can result in either a solid (this is how charcoal is made!), liquid, or gas depending on the speed by which it is heated up (Lesson 21). So if you plan to have a bbq anytime soon you might want to thank pyrolysis.