Doctoral student works toward developing gluten-free children’s snack

Aug 1 2017

Research to develop a gluten-free children's snack made of millet and quinoa has earned doctoral student Gabriela John Swamy the Gerber Endowment in Pediatric Nutrition Graduate Scholarship.

Reflecting on the beginnings of her snack product research, Swamy said, "It was just a simple idea. The challenging part is grains, such as oats, millet and quinoa, have a bitter outer layer that must be removed. Soaking and sprouting was a good pretreatment choice because it also breaks down complex nutrients into simple parts."

Swamy optimized the temperature of the water used to soak the grain and the soaking time and evaluated four germination periods-;24, 48, 72 and 96 hours. Then she ground the grain into flour and used a single-screw extruder to make a puffed cereal.

Sponsored by Feeding Tomorrow, the charitable foundation of the Institute of Food Technologists, the $3,000 Gerber Endowment Scholarship recognizes a full-time graduate student conducting research in nutrition with an emphasis in pediatrics. Swamy was chosen from more than 500 scholarship applicants.

Her adviser, Distinguished Professor Kasiviswanathan Muthukumarappan, who is also the agricultural and biosystems engineering graduate program coordinator, said, "Of the 40 to 50 students I have mentored in the last 20 years, Gabriela is No. 1. She has been an outstanding student and researcher from the very beginning."

"With Dr. Muthukumarappan's expertise and guidance in extrusion, I was able to develop an extrudate," Swamy said. She varied the moisture content in the flour, the temperature at the die section and the screw speed for the germinated flours. She then evaluated the physical and chemical properties of the end products.

When compared to unsprouted grain, the carbohydrate digestibility of the extruded product increased 50 to 60 percent and the protein digestibility by 25 percent, Swamy noted. "I did not add any sugar, just the flour, and there was no off-flavor, no bitter taste to the extrudate."

Swamy presented her research at the 2017 IFT Conference in Las Vegas on June 25-28 through support from the Gerber Endowment scholarship.

She will use the data from her extrusion work to develop a computational model called neural networks as part of her dissertation. The complexity and variability of extruder feed ingredients makes this a highly nonlinear problem, Swamy explained. This work will help prove that neural networks can become valuable tools for food processing systems involving estimation, prediction and control.

Swamy started doing literature reviews and developing proposals in India before coming to SDSU in 2014. In addition, while doing her doctoral work, she and her husband, who has a full-time job in California, had their first child.

"This is definitely a great recognition for me," said Swamy, who is working on product development during the summer internship at Mattson in Foster City, California. Last year, she received a $1,000 graduate scholarship and a $500 travel award for her contributions to the IFT Minnesota section.