Biodiesel Co-Products

Glycerin

Glycerin is a colorless, odorless, hygroscopic, and sweet-tasting liquid.  Glycerin is a sugar alcohol that is a co-product of the transesterification process in the manufacturing of biodiesel. Glycerin removal is a critical step in the biodiesel production process. Pre-treatment and upgrading of glycerin to pharmaceutical grade (>99.7%) can be incorporated within the biodiesel refinery. As the biodiesel industry grows, research and development into new uses and efforts to increase current market penetration are a high priority.

There are approximately 27 food calories per teaspoon of glycerin and it has 60% of the sweetness of sucrose.  Although it has about the same food energy as table sugar, it doesn’t raise blood sugar levels or feed the bacteria that form plaque and dental cavities.

Glycerin has numerous uses:

  • Medical and pharmaceutical preparations – it’s used primarily as a means of improving smoothness, providing lubrication and as a humectant to provide moisture.
  • Serves as an emollient, humectant, solvent and lubricant in personal care products, such as toothpaste, mouthwash, skin care products, hair care products, and soap.
  • Food preservative.
  • Solvent for flavors (such as vanilla) and food coloring.
  • Candy, cakes, meat and cheese casings, and filler in low-fat food products.
  • Manufacturing of emulsifiers for use in butter, margarine and mayonnaise.
  • Flexible and rigid polyurethane foams.
  • Surface coatings, paints and lubricants.
  • Softener and plasticizer to provide flexibility, pliability and toughness. As a plasticizer, it is used in cellophane.
  • Used in lubricating, sizing and softening of yarn and fabric.
  • As a humectant for pet foods to retain moisture and enhance palatability.
  • De-icing and anti-icing fluids.
  • Antifreeze in cryogenic process.
  • Fog machines.

Soybean Meal

While not technically a biodiesel co-product, soybean meal (SBM) plays an important role in a biorefinery’s profitability.  Expanding demand for soybean meal can help ensure an adequate, cost-effective supply of soybean oil for biodiesel production.

Soybean meal is the product remaining after extracting most of the oil from whole soybeans.  The extracted flakes are cooked and ground into meal.

SBM is high in protein and energy and is considered a premium product because of its high digestibility, high energy content and consistency. Due to its high quality protein, SBM is an excellent ingredient for swine, beef and dairy cattle, poultry, and aquaculture feed formulations.  It is also becoming popular for use in pet foods and horse feed.

The poultry industry is the largest consumer of soybean meal, using 50% of U.S. production.  Swine (26%), beef (12%), dairy (6%), and pet foods (3%) respectively use the remaining supply.

For additional information on soybean meal, please visit www.soymeal.org.