Three Things you Need to Know About Bioproducts

 To start off at the beginning some of you may be wondering what bioproducts even are. The USDA describes bioproducts as being produced from renewable sources, most comely plant matter. That was easy! Next question, how are they produced? Well, that's where things get a little more complicated. We will dive into how biomass is made and the 3 largest ways this is done. 

*Most diagrams shown will be for ethanol as this is one of the most common bioproducts produced with the first two emphases.”

 

How are Bioproducts Made?

One, Glucose Extraction (Wet versus dry milling)

This is the first step in producing bioproducts but as it is very important for many bioproducts it will be the first thing we look to keep things easy I will be simplifying these processes down into more mandible bits but if you want to learn more about the sources are always available at the bottom of the blog. Dry milling is usually what you think about when you hear the word. It involves grinding particles together to reduce the particles to a very fine size. Water is added, it's heated up and chemicals and enzymes are added, and you have glucose. 

Corn Dry Milling Diagram

                  Source 6

The other option is wet milling which not only produces glucose but also coin oil, gluten, and the hulls of the corn which can be used for a variety of purposes. Wet milling starts with steeping the corn for around 30-50 hours in a diluted acid solution at around 130 degrees Fahrenheit. Then germ, bran, starch, gluten protein, and the water-soluble nutrients in the corn are all separated from each other and made into 4 co-products for the animal feed industry. The starch and nutrient sweeteners added early are then mixed with chemicals and enzymes and heated up to make the glucose. The important knowledge is glucose is a very important ingredient in manufacturing bioproducts and there are different ways to extract it.

A simplified version of the corn wet milling process

Source 5

Two: Fermentation

Fermentation uses enzymes, fungi, and or bacteria to produce the required product. You probably know yeast is the most widely used ingredient in fermentation making beer, wine, and other spirits, but did you know it is also important in making cheese, yogurt, pharmaceutical products, flavorings, and ethanol. To properly ferment the glucose different ingredients and nutrients will be added to make specific products. Scientists have been coming up with ways to make even more products through yeast fermentation by genetically modifying the yeast so they produce different products or produce those products more efficiently. Nowadays this genetic modification is done in labs however humans have most likely been genetically modifying yeast through artificial selection since the inception of beer in the 16th century. After fermentation, there is usually a distillation process to concentrate the product. For ethanol, this is done multiple times to ensure an essentially water-free product.

3 Combustion, Gasification, and Pyrolysis

I’ll make these short and sweet as they are not as common a way to manufacture bioproducts. Combustion is simply burning things like you would in a fire. It’s usually used for energy. Gasification is when you place biomass under high heat high pressure and low oxygen to create biogas which can be burned directly for energy or it can be processed into specific rations, 2 parts hydrogen gas to 2 parts carbon monoxide to be made into a variety of chemicals. The gas can also be turned into gasoline or diesel. Pyrolysis is when biomass is heated in the absence of oxygen. It can be heated quickly which leads to a liquid being formed, like bio-oil. If the biomass is heated slowly you get a solid, like charcoal.

Source 10

While there are many other ways to create bioproducts in the interest of time I will end it off there. Hope you were able to learn a little more about the world through the view of an (aspiring) environmental engineer!

*As always feel free to dive deeper into glossed-over topics by looking at the sources below*

Sources: 

Factsheet: Bioproducts

1. https://www.usda.gov/sites/default/files/documents/Bioproduct_Factsheet.pdf 

Wet milling vs dry milling: The differences, advantages, and challenges

2. https://hockmeyer.com/blog/articles/wet-milling-vs-dry-milling-the-differences-advantages-and-challenges/#:~:text=In%20dry%20milling%2C%20abrasives%20within,at%20portions%20of%20the%20equipment. 

WHITE PAPER ON THE POSSIBLE PRESENCE OF CRY9C PROTEIN IN PROCESSED HUMAN FOODS MADE FROM FOOD FRACTIONS PRODUCED THROUGH THE WET MILLING OF CORN 

3. https://archive.epa.gov/scipoly/sap/meetings/web/pdf/wetmill18.pdf 

Corn Milling, Processing, and Generation of Co-products

4. https://biofuelscoproducts.umn.edu/sites/biofuelscoproducts.umn.edu/files/2021-09/ddgs-techinfo-pro-20.pdf 

Corn Wet Milling process

5. https://www.researchgate.net/figure/Diagram-for-corn-wet-milling-process-flow-to-extract-corn-starch-and-output-products_fig2_357401789 

Ethanol Production Processes

6. http://indianaethanolproducers.org/dry_milling.html 

Fermentation

7. L19. Fermentation: BBE 1002 (001) Biorenewable Resources (Spring 2024) (umn.edu)

 

The Domestication of Beer Yeast

8. https://www.homebrewersassociation.org/how-to-brew/domestication-beer-yeast/ 

Other Pathways to Products

9. L21. Other Pathways to Products: BBE 1002 (001) Biorenewable Resources (Spring 2024) (umn.edu) 

Comparison of combustion, gasification, pyrolysis, and torrefaction, with major products

10. https://www.researchgate.net/figure/Comparison-of-combustion-gasification-pyrolysis-and-torrefaction-with-major-products_fig1_312679682