Location: Dairy and Functional Foods ResearchTitle: Structural Characterization of Red Beet Fiber Pectin
|Chau, Hoa - Rose|
|NUNEZ, ALBERTO - Retired ARS Employee|
|DIENG, SENGHANE - Ingredion, Inc|
|HEUBERGER, EUGENE - Ingredion, Inc|
|HIRSCH, JULIE - Ingredion, Inc|
Submitted to: Food Hydrocolloids
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/24/2022
Publication Date: 2/11/2022
Citation: Hotchkiss, A.T., Chau, H.K., Strahan, G.D., Nunez, A., Simon, S., White, A.K., Dieng, S., Heuberger, E., Yadav, M.P., Hirsch, J. 2022. Structural characterization of red beet fiber pectin. Food Hydrocolloids. 129:107549. https://doi.org/10.1016/j.foodhyd.2022.107549.
Interpretive Summary: Consumers already consider red beet to be a healthy food consumed fresh in salads, or juices, yet more data is needed in order to obtain health claims for this vegetable. Therefore, researchers in Wyndmoor, PA described in greater detail the structural composition of a commercial red beet fiber remaining after juice processing. Health-promoting dietary fiber carbohydrate and protein were present with low levels of fat. Some of these compounds are known to promote the growth of health-beneficial human gut bacteria or may prevent chronic diseases. The red beet fiber composition can also act as an emulsion stabilizer and thickening agent in food formulations. This information will be useful to understand the multiple health benefits of red beet and provide more value for this specialty crop.
Technical Abstract: Red beet fiber structure function relationships were determined. The pomace, that remained after red beet commercial puree extraction, contained dietary fiber (50.8%) that was largely insoluble (40.1% vs. 10.7% soluble dietary fiber) pectin, sucrose (8.07%), fructose (1.14%) and glucose (2.33%) free sugars, protein (10.2%), and fat (3.02%). Malto-oligosaccharides and methyl-esterified, acetylated and feruloylated rhamnogalacturonan I oligosaccharides with branched arabinogalacto-oligosaccahride side chains were detected with MALDI-TOF MS and NMR analysis. Red beet pectin, acid-extracted with a microwave using 10 min and 80C conditions, had high molar mass (1036 kDa) with viscosity that was similar to sugar beet pectin extracted under the same conditions. A random coil shape was confirmed for red beet pectin microwave extracted under 3 min and 120C conditions and red beet pomace, water soluble and insoluble fiber fractions. Longer microwave extraction times and microwave extraction at pH 1 produced compact spherical red beet pectin with lower molar mass and viscosity. These structural properties suggest that red beet pomace functions as an emulsion stabilizer, thickening agent and prebiotic food ingredient based on previously published literature, and much of this activity remained with the pomace following juice extraction.