Structural modification and dynamic in vitro fermentation profiles of precooked pea starch as affected by different...

Area of Science:

• Food Science
• Microbiology
• Biochemistry

Background:

• Starch structure influences its digestion and fermentation by gut microbiota.
• Drying methods can alter starch's physical and chemical properties.

Purpose of the Study:

• To investigate how different drying methods affect pea starch structure.
• To determine the impact of these structural changes on in vitro human gut fermentation.
• To correlate starch structure with short-chain fatty acid (SCFA) synthesis and microbial community shifts.

Main Methods:

• Pea starch was subjected to oven-drying, infrared-drying, microwave-drying, and freeze-drying.
• Dried starches were anaerobically fermented by human gut microbiota for 24 hours.
• Structural analysis included X-ray diffractogram (XRD) and 13C CP/MAS NMR.
• SCFA production and microbial responses were quantified.

Main Results:

• Oven-dried pea starch (ODPS) exhibited the highest crystallinity and specific structural features.
• Changes in spectral ratios (R1047/1022 and R995/1022) during fermentation correlated with increased molecular order.
• Higher ordered starch structures favored Firmicutes, while looser structures favored Bacteroides.
• ODPS fermentation led to the highest Bifidobacterium levels and propionate/butyrate concentrations.

Conclusions:

• Drying methods significantly modify pea starch structure, influencing its fermentability.
• Starch's structural order dictates its interaction with specific gut bacteria.
• Tailoring drying processes can optimize starch's prebiotic properties for targeted gut health benefits.