A Comparative Study of Pectin Green Extraction Methods from Apple Waste: Characterization and Functional Properties

Area of Science:

• Food Science
• Biochemistry
• Chemical Engineering

Background:

• Traditional pectin extraction methods are inefficient, leading to reduced quality, yield, and functional properties.
• Apple pomace, a food processing byproduct, is a rich source of pectin.
• Developing novel extraction techniques is crucial for optimizing pectin production.

Purpose of the Study:

• To produce high-quality pectin from apple pomace using nonconventional extraction methods.
• To compare the efficacy of microwave, ultrasound, citric acid, and organic acid mixture methods against conventional extraction.
• To evaluate pectin yield, thermal behavior, functional groups, antioxidant activity, and functional properties.

Main Methods:

• Pectin extraction using conventional methods, microwave, ultrasound, citric acid, and an organic acid mixture (citric acid, ascorbic acid, acetic acid).
• Comparative analysis of pectin yield, galacturonic acid index, structural properties (SEM), surface charge, thermal stability (TGA), and antioxidant activity.
• Evaluation of functional properties of the extracted pectin.

Main Results:

• Citric acid extraction yielded the highest pectin yield (22%).
• Organic acid mixture extraction maximized the galacturonic acid index (87.58%), improved structural properties, increased particle charge (-59.42), and enhanced thermal stability.
• Microwave-extracted pectin exhibited 3-4 times higher antioxidant activity compared to other methods.
• Nonconventional methods generally improved pectin quality and functional properties.

Conclusions:

• Extraction using organic acids, microwave, and ultrasonic methods significantly enhances pectin quality and functional properties.
• The improved pectin is suitable for high-temperature food applications, such as bakery products.
• Nonconventional extraction techniques offer a sustainable and efficient alternative to traditional methods for pectin production.