The Schoenfuss lab research areas focus on dairy product chemistry and functionality, and how the formula and manufacturing process affects natural and process cheeses, fermented milks, and other dairy ingredients. We use analytical tools to measure chemical and physical properties, and sensory methods to evaluate quality differences. 

Current Projects:

Improving intermediate wheatgrass (Thinophyrum intermedium) dough properties using dough conditioners 

Intermediate wheatgrass (IWG) is a sustainable, perennial crop that is similar to wheat.  However, doughs made with IWG have different rheological properties when compared to doughs made from wheat.  We are studying the impact of different dough conditioners on the functionality of IWG, particularly extensibility and resistance to extension.  Next steps include investigating the baking quality of IWG breads with different dough conditioners at various refinement levels.

Polymerization of lactose by twin screw extrusion to create soluble fiber

Our lab has demonstrated that extrusion of lactose with heat and a chemical catalyst can polymerize the sugar to longer oligomers that analyze as soluble fiber. We have evaluated the chemical properties of this material and how processing conditions affect these properties.  Currently, we are furthering our understanding of polylactose by using a microwave reactor benchtop method to evaluate the impact of formulation on the polymerization reaction and a carbon filtration method has been developed for polylactose decolorization and purification. The goal is to have a value-added fiber ingredient created from lactose that can be used in food and feed applications.

Producing astaxanthin from dairy co-products

Cheese making produces the low value waste product de-lactosed whey permeate, and we are in search of novel uses for this by-product. We are investigating the feasibility of a value-added use for de-lactosed whey permeate as a feed material for the algae Haematococcus pluvialis to produce astaxanthin. Astaxanthin is an antioxidant and the main carotenoid that gives salmon and shrimp their red color. 

Previous Projects:

Reduction of sodium in blue cheese with and without the use of KCl

Reducing sodium in cheese is problematic not only because it contributes to flavor, it also contributes to formation of the proper texture, the ability to remove water during manufacture, and controls cultures and nonstarter miccroorganisms in the cheese. With blue cheese, the activity of the mold Penicillium roqueforti is also controlled by the salting rate. Blue cheese is also surface salted, and our Minnesota Blue is made by dry rubbing portions of the salt to the surface of the cheese wheel over a 4 day period. KCl is often used when sodium chloride is reduced in food because it can exert a similar effect to salt on controlling microbial activity in a food. This study investigates the migration of sodium and potassium into the cheese wheel, and the effects of a 25% reduction on chemical and sensory properties in the cheese.

Use of microparticulated whey – hydrocolloid aggregates as filler gels in low fat Cheddar cheese

Fat reduction in cheese results in a dense, firm product that has an objectionably firm texture. We are investigating the ability of hydrocolloids to bind to microparticulated whey proteins to disrupt the protein network in low fat cheese to reduce firmness and improve texture. 

Use of FTNIR to measure intact casein in Cheddar cheese

When making process cheese, natural cheese is heated with various salts to emulsify the fat in the cheese. The amount the protein in the cheese has been hydrolyzed effects the process cheese properties. Having the desired ratio of intact protein from batch to batch is important to reduce variability and control product quality. We are developing a rapid way to evaluate this parameter in cheese.