Apple Pomace Fermented with Non-Saccharomyces Yeast as a Factor Modulating Gut Microbiota

Area of Science:

• Food Science
• Microbiology
• Nutritional Science

Background:

• Agro-industrial by-products can be valorised into functional ingredients via fermentation.
• Fermentation offers a route to develop ingredients targeting gut microbiota modulation.
• Apple pomace is a readily available by-product with potential for functional ingredient development.

Purpose of the Study:

• To evaluate the impact of low-temperature fermented apple pomace on human gut microbiota structure and metabolic activity.
• To assess the stability of fermented apple pomace under simulated gastrointestinal conditions.
• To explore the potential of fermented apple pomace as a functional food ingredient.

Main Methods:

• Utilized the Simulator of the Human Intestinal Microbial Ecosystem (SHIME®) to simulate human gut microbiota.
• Fermented apple pomace at a low temperature (15 °C) using cold-adapted yeast.
• Analyzed microbial composition, metabolic activity, and short-chain fatty acid profiles.

Main Results:

• Fermented apple pomace demonstrated stability under gastrointestinal conditions.
• Supplementation altered gut microbiota composition, increasing Akkermansia, Coriobacteriaceae, and Parabacteroides while decreasing Bifidobacterium, Klebsiella, Serratia, and Raoultella.
• Reduced proteolytic fermentation metabolites and a more stable metabolic profile were observed.
• Short-chain fatty acid profiles shifted towards physiological reference ranges.

Conclusions:

• Low-temperature fermentation enhances apple pomace's functional properties for gut microbiota modulation.
• Fermented apple pomace promotes a more stable gut microbial ecosystem.
• Fermented fruit by-products represent sustainable ingredients for gut health dietary strategies.