Inulin-propionate ester as a novel food in cereal bars and fruit smoothies: total propionate by HPLC-RID after hydrolysis, free acid as the degradation indicator, and fat — Soxhlet without acid hydrolysis
Commission Implementing Regulation (EU) 2026/1219, published on 10 June 2026, authorises inulin-propionate ester (applicant: Imperial College Hammersmith Campus) in cereal bars up to 17 g/100 g and in fruit smoothies up to 3 g/100 mL. Following EFSA’s remark, the Commission added to the specification chemical and microbiological parameters that the applicant had not included.
- Specification: inulin 65–95 %, free propionic acid < 1 %, esterified propionic acid 5–35 %, ester after hydrolysis 100–112 %, total nitrogen < 0.1 g/100 g, fat < 0.5 g/100 g, sodium < 0.1 %; arsenic < 0.1 mg/kg, cadmium < 0.01 mg/kg, lead and mercury < 0.05 mg/kg; aerobic bacteria < 1000 CFU/g, E. coli and Enterobacteriaceae < 10 CFU/g, no Listeria spp. in 25 g.
- Methods in the EFSA opinion (25 June 2025): inulin — validated UV–Vis spectrophotometric method (total carbohydrates); total propionate — hydrolysis with concentrated orthophosphoric acid (80 °C, 1 h) and HPLC with refractive index detection (RID); esterified = total minus free. In 5 batches: inulin 80.8–89.9 %, esterified propionate 18.59–25.31 %.
- The first fat determinations (hot acid hydrolysis, gravimetry and NMR) gave fat above the limit of quantification in some batches and relatively high trans fatty acids. At EFSA’s request they were repeated with the accredited Soxhlet method without acid hydrolysis from Regulation (EC) No 152/2009 — all batches < 0.5 g/100 g.
- Free propionic acid (GC-FID) is the degradation indicator: in the product it was stable up to 45 months (one batch). In foods it was determined by size-exclusion ion chromatography with conductivity detection (LOD < 0.005 g/100 g); the applicant withdrew bread from the application because it released 0.55 % acid. Microbiology was tested according to EN ISO 4833-2, ISO 21528-2, EN ISO 16649-2 and EN ISO 11290-1.