Jason Koski (UPhoto)
Jason Koski (UPhoto)

From Gummies to Water Purification Filters

by Jackie Swift

Ensuring food products meet with consumer expectations isn’t easy. Take vitamin C–infused gummies: keeping the vitamin C stable is so tricky that gummy manufacturers regularly add up to 200 percent more vitamin C to the product than they list on the label to ensure that the gummies still have the minimum amount up to their expiration date. However, thanks to Alireza Abbaspourrad, Food Science, and his team, manufacturers of vitamin gummies now have the option of incorporating a new encapsulation process into their manufacturing that ensures vitamin C stability and does away with the need to overcompensate.

“My lab has developed platforms to encapsulate a broad range of food ingredients and bioactives,” Abbaspourrad says. “It can be vitamins, antioxidants, natural colorant, probiotic bacteria, a peptide—anything that requires protection and a controlled-release platform. We protect the actives by applying food-grade coatings around them that are designed to release the cargo under predefined conditions.”

Encapsulation is just one of many research areas Abbaspourrad pursues. He revels in collaborative work, and his lab includes 40 people with an array of expertise: polymer scientists, physicists, microbiologists, materials scientists, food scientists, and chemical, mechanical, and electrical engineers. They bring their disciplines to bear on a range of questions, from stabilizing natural food colorants so they last longer to engineering microfluidic platforms for detecting pathogens. Often the researchers conduct their work in partnership with federal agencies such as the National Institute of Food and Agriculture, as well as with a wide range of companies such as Nestlé, PepsiCo, Tate & Lyle, and the second-largest chemical producer in North America, BASF Corporation.

From Food Waste to Valuable Byproduct

One area of interest for Abbaspourrad is the conversion of agriculture and food waste to byproducts of value. He and his colleagues recently turned their attention to grape pomace—the solid remains of grapes after they are pressed. “Around 14 million tons of pomace are produced globally every year by the grape industry,” Abbaspourrad says. “The majority ended up in landfills.” So the researchers took the grape seed from the pomace and used a chemical treatment to extract nanofibers from the seeds. From that, they made a foam that can be used as a filter for water purification.

In another project, the Abbaspourrad lab used an enzyme to process lactose, a byproduct of the dairy industry, into galacto-oligosaccharides (GOS), a prebiotic food. GOS is often added to products like infant formula to provide food for probiotics—or good bacteria—in a baby’s gut.

“A process has existed for some time to convert lactose to GOS, but the conversion is low,” Abbaspourrad says. “Our enzymatic approach takes the galactose parts of the lactose and puts them all together to form a long chain, which is GOS. Now we can take lactose, which is left over from yogurt making, cheese making, and milk processing in general, and more quickly convert it into something that is usable for food application.”

Microfluidic Platforms for Many Uses

Abbaspourrad also has a large section of his lab devoted to microfluidics, a platform that allows the researchers to design bioassays to detect pathogens, such as bacteria and viruses, as well as to pinpoint which antibiotic is most efficacious for treating a certain bacteria and what dosage is needed to kill the pathogen. The researchers inject bacteria into flow channels on small chips fitted out with multiple chambers where the bacteria separate out from one another. Then they submit the bacteria to different types of tests—for instance, injecting antibiotics at different concentrations into the chambers.

“The bacteria in each chamber experience different concentrations of the antibiotic in a concentration gradient,” Abbaspourrad explains. “We can see in which chamber the bacteria grew and which they didn’t. This helps us identify the minimum inhibitory concentration we need to suppress its growth.”

“A lot of the questions we pursue are not only related to food, chemistry, physics, or engineering; they’re a combination of all of these.”

Knowing the minimum inhibitory concentration of an antibiotic helps address the problem of antibiotic resistance in bacteria. “When someone has an infection, there’s a wide range of antibiotics you can give them,” Abbaspourrad says. “You start with the weakest one and, if it’s not effective, you use more or stronger antibiotics.” This hit-or-miss approach means that bacteria can be exposed to many types of antibiotics, often in high dosages, which stimulates bacteria to mutate and become resistant. The Abbaspourrad lab’s approach seeks to counter this.

In an unexpected twist, Abbaspourrad has also applied his microfluidic platform to the study of sperm navigation for in vitro fertilization (IVF). “We use the same microfluidic device, with some design changes, for separation of sperm to capture those with the highest motility so they can be used for IVF,” he explains.

A Cross-Disciplinary Approach

Abbaspourrad originally trained as an organic chemist, then worked on micro- and nanoencapsulation, and research and development for a German paint firm before starting his own paint company in his hometown of Tehran. Eventually, he moved on to designing microsensors and microchips for the oil industry in Brazil and then joined the Harvard University School of Engineering and Applied Sciences as a postdoctoral associate, where he first worked with microfluidics. When he came to Cornell in 2015, he combined his varied background and expertise to build his lab team.

“Because we have a very big, cross-disciplinary team, we can handle a wide range of research,” he says. “A lot of the questions we pursue are not only related to food, chemistry, physics, or engineering; they’re a combination of all of these. That’s why I really love food science; it is interdisciplinary, and we get to do so many different things that bring multiple fields of science together.”