Extraction of pectin from apple pomace

Pectins are biopolymers, which exist inside the cell walls. Apples are the richest source of pectin comparing to other fruits and vegetables. Pectin has many health benefits and might be used in regenerative medicine as drug delivery systems, as dietary fiber, as edible films, to neutralize cholesterol and to lose excess weight. Five cultivars grown in Latvia, Tukums Municipality, Pūre parish in the season of the year 2019: ‘Zarja Alatau’, ‘Antonovka’, ‘Antejs’, ‘Sinap Orlovskij’ and ‘Alesja’ were selected for extraction. The study was carried out with the aim to investigate the extraction possibilities of pectin from apple pomace using pH decreasing untraditional acidifying agent – lemon juice. Pectin from apple pomace was extracted using the hot acid extraction method. The content of pectin and sugars (glucose, fructose, sucrose, total sugars) was determined by the colorimetric method and HPLC Shimadzu Prominence LC-20 Refractive Index Detector (RID-10A). The highest level of pectin was determined in the cultivars ‘Antejs’ (4.9 g per 100 g), ‘Sinap Orlovskij’ (4.8 g per 100 g) and the lowest in ‘Antonovka’ (3.9 g per 100 g). The results demonstrated that the highest concentrations of total sugars of glucose, fructose and sucrose were in the cultivars ‘Antejs’ (Glucose 1.2, Fructose 6.6, Sucrose 4.1 = Total sugars 11.9 g per 100 g) and ‘Alesja’ (Glucose 1.2, Fructose 6.6, Sucrose 3.6 = Total sugars 11.4 g per 100 g), the lowest in ‘Antonovka’ (Glucose 0.9, Fructose 6.0, Sucrose 1.4 = Total sugars 8.3 g per 100 g). The best content of pectin and total sugars from all cultivars was detected in the apple cultivar ‘Antejs’.