|Bett Garber, Karen|
|BICE, DOUGLAS - United Sorghum Checkoff|
Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 3/26/2019
Publication Date: 11/6/2019
Citation: Eggleston, G., Bett Garber, K.L., Triplett, A., Boue, S.M., Bechtel, P.J., Bice, D. 2019. Total Phenolics, Antioxidant activity, and color in sweet sorghum syrups compared to other commercial syrup sweeteners. Meeting Proceedings. 2018,vol. 2.
Interpretive Summary: With the intention of expanding the production of sweet sorghum syrup usage in the USA, this research was accomplished to report the health benefits of sweet sorghum syrup over other commercially available food-grade syrups. Data from two antioxidant capacity methods (ORAC and DPPH) were reported, as well as color differences. Sweet sorghum syrups contained dramatically higher contents of total antioxidant capacities compared to honey, high fructose corn syrup, corn syrup, agave syrup, rice bran syrup, cane syrup, and maple syrup. The color of the syrups was strongly related to total phenolic content. Color measurement at pH 9.0 at 320 nm wave length could be useful for indirectly measuring total phenolics and antioxidant capacity in an industrial setting. Further studies are warranted.
Technical Abstract: Knowledge of the nutritional and dietary content of sweet sorghum syrups compared to other commercial food-grade syrups, will expand sorghum utilization as a food source and facilitate its large-scale marketing. Phenolic, antioxidant activity, and related color data for commercial high fructose corn syrup (HFCS), corn, honey, maple, agave, rice, and grain sorghum syrups (three brands) were compared to ten commercial sweet sorghum syrups. Sweet sorghum syrups contained dramatically higher (P<0.05) total phenolic contents TPC (6471 ± 1823 mg/L) compared to the other syrups (596 ± 497 mg/L). TPC variation among sweet sorghum brands was 28.2%CV which was much lower than 83.3%CV for the other syrups. Antioxidant activities of the syrups were measured as 2,2-diphenyl-1-picryl hydrazyl (DPPH) antioxidant radical scavenging activities (RSA) and oxygen radical absorbance capacity (ORAC) values. High fructose corn syrup (HFCS), corn, white grain sorghum, and rice syrups had negligible and low DPPH-RSA and ORAC values, respectively. TPC, DPPH-RSA, ORAC, and color values of the sweet sorghum syrups were dramatically (P<0.05) higher than for the other syrups and highly related. Color of the syrups, measured at pH 4.0, 7.0, and 9.0 and wavelengths of 280, 320, 420, and 580 nm, was strongly related to the TPC especially at pH 9.0 (sensitive to phenolic colorants) and 320 nm (sensitive to hydroxycinnamic derivatives) closely followed by 420 nm. Color easily measured at pH 9.0 and 320 nm could be useful indirect measure of total phenolics and antioxidant capacity for industry and further studies are now warranted.