Extraction and characterization of pectin from passion fruit peel, and its application in synbiotic ice cream: A study from Phetchabun, Thailand

The study investigated the optimal condition for pectin extraction from passion fruit peel (PFP) cultivated in Phetchabun, Thailand. The maximum yield was obtained with a PFP powder–to–water ratio of 1:30 (w/v) and an extraction time of 15 min. The obtained PFP–extracted pectin (PFPEP) exhibited a higher degree of esterification, total phenolic content (TPC), and antioxidant capacity (AOC) compared to commercial pectin (CP) (P < 0.05). Interestingly, arabinose was present in PFPEP but absent in CP. The growth of probiotics was significantly enhanced by the medium containing PFPEP. The addition of PFPEP in synbiotic ice cream increased overrun value, while the melting rate, pH, and color intensity decreased compared to the ice cream without pectin. Sensory evaluation indicated that PFPEP–supplemented ice cream received the highest attribute scores (P < 0.05). Furthermore, PFPEP–supplemented ice cream increased TPC, AOC, and viability of L. acidophilus TISTR 2365 during storage at −18 °C for 120 days, with no detection of pathogenic bacteria. These findings suggest that PFPEP has a high potential to be a functional ingredient applied in the food industry.