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ARS Home » Southeast Area » Little Rock, Arkansas » Arkansas Children's Nutrition Center » Microbiome and Metabolism Research » Research » Publications at this Location » Publication #407896

Research Project: Impact of Maternal Influence and Early Dietary Factors on Child Growth, Development, and Metabolic Health

Location: Microbiome and Metabolism Research

Title: Modification of starch digestibility and phenolic bioaccessibility in phenolic-rich flours by physical treatments with ferulic acid followed by vacuum oven and freeze-drying

Author
item FIECKE, CHELSEY - Arkansas Children'S Nutrition Research Center (ACNC)
item KALAMBUR, SATHYA - Pepsico
item BHASKAR, AJAY - Pepsico
item FERRUZZI, MARIO - Accelerated Genetics

Submitted to: LWT - Food Science and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/20/2024
Publication Date: 2/28/2024
Citation: Fiecke, C., Kalambur, S.B., Bhaskar, A., Ferruzzi, M.G. 2024. Modification of starch digestibility and phenolic bioaccessibility in phenolic-rich flours by physical treatments with ferulic acid followed by vacuum oven and freeze-drying. LWT - Food Science and Technology. 197:115889. https://doi.org/10.1016/j.lwt.2024.115889.
DOI: https://doi.org/10.1016/j.lwt.2024.115889

Interpretive Summary: Modification of glycemic properties in flour ingredients could lead to healthier snacks by reducing starch digestibility. Formation of starch-ferulic acid (FA) complexes by acidic steeping with purified phenolics in model systems increases resistant starch content and reduces glycemic responses in animal models. We examined the potential to generate similar complexes in phenolic-rich black rice and purple maize flours. Starch-phenolic complexation was performed using an acidic steeping method. Phenolic content, in vitro starch digestibility, and phenolic bioaccessibility were assessed. Acidified steeping with FA modifies starch digestibility, however, is limited in phenolic-rich ingredients like black rice and purple maize due to FA loading capacity and processing loss of phenolics from these ingredients.

Technical Abstract: Formation of starch-ferulic acid (FA) complexes by acidified water steeping in model systems has been shown to increase resistant starch (RS) content and reduces glycemic responses in animal models. However the generation of similar complexes from in situ interactions in phenolic-rich flours (black rice, BR; purple maize, PM) and their impacts on starch digestibility and phenolic bioaccessibility remain unclear. Using an acidified water steeping method previously reported in pure starch-phenolic models, potato starch (PS), BR and PM flour slurries were prepared with FA at a 20:1 and 8:1 ratio in HCl-acidified water (pH 2). The steeping process reduced phenolic content (~75%) and increased starch digestibility. Steeped PM flours with FA demonstrated reduced estimated glycemic index compared to steeping alone, consistent with formation of starch-FA complexes. Ferulic acid loading capacity on PS (33-114 mg/g starch) was greater than for PM and BR flours (12-28 mg/g starch). In PS and flours, increasing the amount of FA decreased FA bioaccessibility. Steeping increases cyanidin 3-O-glucoside bioaccessibility, while FA addition reduced bioaccessibility. Greater effects on starch digestibility occurred in purified starch compared to phenolic-rich flours due to limited FA loading capacity and loss of native phenolics during steeping of phenolic-rich flours.