Extraction and Functional Properties of Water‐Soluble Dietary Fiber from Apple Pomace

Abstract

The extraction of water‐soluble dietary fiber (SDF) from apple pomace (AP) by cellulase, microwave‐ and ultrasound‐assisted methods was studied in comparison with conventional acid method. The functional properties of extracted SDFs were further evaluated, and the speciality of each method was clarified in order to suggest the right method to adopt for practice. Results indicated that AP is rich in SDF, which is significantly potential to be applied in food processing. Acid hydrolysis of AP gave 10.3% of SDF, whereas ultrasound‐assisted extraction (UAE) provided a yield of 16.4% after 40 min of sonication. Microwave‐assisted extraction (MAE) gave a slightly lower yield (14.9%) than UAE, but it showed a drastic efficiency, wherein the yield was achieved after 2 min of irradiation. The hydrolysis of AP by cellulase occurred with the highest SDF yield (18.7%) among all the methods used. The functional properties of SDF were improved by UAE, MAE and cellulase extraction, wherein the water retention and swelling capacities were increased more considerably than the oil retention capacity. Especially, cellulase showed a remarkable performance in improving the hydration property. Practical Applications A large amount of apple pomace (AP) was produced as the by‐product of apple processing in China. Its disposal is of significance in consideration of resource utilization and environmental protection. Therefore, the results of this study can promote the full use of AP and similar industrial wastes, and also help to avoid possible pollution. In addition, the comparison of acid, cellulase, microwave‐ and ultrasound‐assisted methods suggests the right method to adopt SDF extraction method for practice.

Fruit and Vegetable Waste: Bioactive Compounds, Their Extraction, and Possible Utilization

“…Yan and Kerr () observed that TDF ranged from 442 to 495 g/kg in vacuum‐dried pomace and was not significantly different from the freeze‐dried pomace (480 g/kg). Ultrasound‐assisted extraction provided higher soluble dietary fiber yield in apple pomace than when microwave or acid hydrolysis techniques were used (Li and others ).…”

Green extraction of soluble dietary fibre from coffee silverskin: impact of ultrasound/microwave‐assisted extraction

“…Similar findings were reported by other studies (Ying et al , ; Bélafi‐Bakó et al , ; Sommano et al , ). Li et al () studied MAE for SDF from apple pomace. The SDF yield by MAE (14.9%) was higher than by conventional method (10.3%) with drastic efficiency, as the conventional method was conducted for 4 h, while MAE was operated only 2 min.…”

Protopectinase production byPaenibacillus polymyxaZ6 and its application in pectin extraction from apple pomace

“…The major sources for commercial pectin production are apple pomace, citrus peels, and sugar beet pulp (Mesbahi, Jamalian, & Farahnaky, ). Apple pomace is the solid residue produced in a large quantity during apple juice extraction in the industry (Li, He, Lv, & He, ). More than 100 million tons of this by‐product resource is produced in China every year (Cheng, Sun, Du, & Jian, ).…”