Partially Hydrolyzed Guar Gum (PHGG / Sunfiber)

Partially Hydrolyzed Guar Gum (PHGG) is a soluble dietary fiber derived from guar beans (Cyamopsis tetragonoloba) via enzymatic hydrolysis, yielding a low-molecular-weight galactomannan (MW ~20,000–30,000 Da versus ~2,000,000 Da for native guar gum). It is composed predominantly of a mannose backbone (β-1,4-linked) with galactose side chains at approximately a 2:1 mannose-to-galactose ratio. As a purified fiber isolate, it contains negligible protein (<1%), fat (<0.5%), and simple sugars, with fiber content comprising ~75–85% of dry weight (approximately 6–8g fiber per 10g serving of Sunfiber-grade PHGG). It provides minimal caloric value (~1–2 kcal/g due to partial fermentation). It contains no significant vitamins or minerals in meaningful quantities. Key bioactive property is its prebiotic galactomannan structure, which resists small intestinal digestion and reaches the colon intact for fermentation. Bioavailability as a nutrient source is low, but its functional bioavailability as a microbiome substrate is high — fermentation yields short-chain fatty acids (SCFAs), particularly butyrate, propionate, and acetate, estimated at 40–60 mmol/L colonic concentration at typical doses. It is notably low-viscosity compared to other soluble fibers (e.g., psyllium, beta-glucan), making it well-tolerated with minimal bloating at doses of 5–10g/day.