Nutrition and Supplements Vitamins and minerals Solgar Ester C Plus 500 mg Capsules 50 Ester-C Plus is exclusively formulated by Solgar and provides a patented pH-neutral (non-acidic) Ester-C vitamin C that is gentle on the stomach. The vitamin C metabolites in Ester-C have a positive impact on vitamin C retention in cells, providing additional benefits. A special manufacturing process is used to form a unique complex of calcium ascorbate metabolites. This well-preserved complex also incorporates natural bioflavonoids and acerola berries along with rosehip fruit.*