A polyuronan blend giving novel synergistic effects and bake-stable functionality to high soluble solids fruit fillings

The effects of High M alginate, LE pectin and a combination, GRINDSTED® FB 850 Stabiliser System (FB 850), giving bake-stable functionality in real, high soluble solids (72%) fruit fillings, are studied as a function of pH, fruit type, syneresis, and gel strength above the accepted bake-stable index of 80%. For acceptable bake stability, alginate showed a broad fruit, and thereby calcium tolerance (24.2–34.8 mg Ca/g Alginate), and a narrow pH range (3.8–4.0); contrary pectin showed a narrower calcium tolerance (20.7–29.4 mg Ca/g Pectin) but broader pH range (3.4–4.0) and FB 850 showed a calcium tolerance similar to pectin, (25.1–33.8 mg Ca/g FB 850) in terms of range, and a pH tolerance broader than both alginate and pectin (3.3–4.3). In alginate, syneresis was absent over the narrow pH range (3.8–4.0); pectin showed syneresis at lower pH (3.4–3.7), and in FB 850 syneresis was prevented over the entire pH range (3.3–4.3). FB 850 required lower gel strengths to achieve bake stability compared to pectin and alginate. For FB 850, pectin and alginate, thixotropy decreased (80, 48 and 23%, respectively), whilst the observed increase in elasticity and relative gel strengths, similarly suggested decreasing pumpability over the same given order. Pectin–alginate chain–chain associations cannot readily explain the synergistic effects seen in FB 850 because of high pH, initial presence of calcium and the low ester pectin. We therefore propose the synergy is driven by antagonistic competition between pectin and alginate for the calcium. We describe this as a mixed-independent system.