Most cooks are familiar with the thickening properties of corn starch, but potato starch is every bit as much up to the job, say scientists with Agriculture and Agri-Food Canada (AAFC). They’re working on a project to further examine the structure and functional properties of potato starch, improve the nutritional quality of potato foods, and develop new uses for modified potato starch in food processing, pharmaceutical and industrial applications.
Potato starch is currently used by the food processing industry as a general thickener, binder, texturizer, anti-caking or gelling agent. It also shows up in finished products such as snack foods, processed meats, baked goods, noodles, shredded cheese, sauces, gravies and soups, as well as in yeast filtration.
AAFC’s research team is lead by Dr. Qiang Liu, a food scientist at the Guelph Food Research Centre in Guelph, Ont. The project includes plant breeders, food scientists, molecular biologists and plant production specialists from AAFC research centres across Canada including Lethbridge, Alta. St-Hyacinthe, Que., Fredericton, N.B., Guelph and Ottawa.
“Our team is examining many aspects and uses of potato,” says Liu. “We are working directly with our potato breeders in Fredericton and Lethbridge to produce new potatoes with desirable starch structure and increase the content of ‘resistant starch’ and ‘slowly digestable starches’ in the processed potato foods.”
Resistant starch refers to the starch in starchy foods that is not digested or absorbed in the small intestine. This resistant starch reaches the large intestine essentially intact where it is considered to have similar physiological effects and health benefits as fibre – that is, it provides bulk, protects against colon cancer, improves glucose tolerance and insulin sensitivity, and lowers plasma cholesterol and triglyceride concentrations.
Members of the research team are studying aspects of resistant starch formation and characteristics during the food processing, starch digestion and its effect on human nutrition and disease prevention. This information may be a valuable tool in treating and preventing several health issues such as diabetes and cardiovascular disease. “From here we hope to formulate a value-added potato starch with improved nutritional properties. It will benefit both consumers and the food processing industry,” says Liu. “The possibilities are endless.”
— Debbie Lockrey-Wessel