Preface

Scientists and technologists are particularly interested in pectin for its nutritional content and because of its versatile uses since ancient times as an important source of food fiber and as a gelling agent in foods. This book is a cutting-edge, multidisciplinary reference work that will promote pectin research by combining and fostering new perspectives and methodologies from different fields of study. The extraction, processing, and uses of pectin in the food and pharmaceutical industries are all covered.

I'd like to express my deepest gratitude to all the authors who have worked on this publication. Last but not least, I'd like to thank my family and other supporters who have helped me stay motivated during this project.

> **Dr. Maruf Ahmed** Professor, Department of Food Processing and Preservation, Hajee Mohammad Danesh Science and Technology University, Dinajpur, Bangladesh

**1**

**Chapter 1**

**Abstract**

Millet Flour

ing antioxidants or antimicrobials.

**1.1 Application of biodegradable films**

millet, fruit wastes

**1. Introduction**

Extraction of Pectin from Orange

Fossil-based plastic is a popular material for food packaging. It can cause negative environmental consequences due to its low biodegradability. To address this challenge, a pectin-based edible plastic with added nutritional value by incorporating whole-grain kabog millet flour was prepared. The pectin in the films was extracted by microwave-assisted and enzymatic procedures from orange peel wastes. The extracted pectin was tested for its degree of esterification using Fourier-transform infrared spectroscopy, its molecular weight and behavior in aqueous solutions using size-exclusion chromatography, and its monosaccharide composition using ionexchange chromatography. Biodegradable and edible pectin films were produced and tested for their mechanical properties: maximum strain, maximum stress, and water contact angle. The results showed a significant increase in hydrophobicity of the film surface by adding whole-grain kabog millet flour. The maximum strain of the film, however, was reduced to around 80% upon the addition of the whole-grain kabog millet flour. Enzymatically-extracted pectin increased the film hydrophobicity. Hydrophobic surfaces have higher water resistance; thus, the enzymatically-extracted pectin can be developed for further applications. Due to the low elasticity of the films, a possible application would be as direct coating of fruits and vegetables incorporat-

**Keywords:** pectin, microwave-assisted, enzymatic extraction, edible films, kabog

In 2016, 335 million tons of plastics were produced globally, of which the majority were single-use plastics. Approximately 40% of the produced plastics were used for packaging [1]. This large volume of plastics leads to several problems: most oilbased plastics are highly resistant to biodegradation, which means if they enter the

Peel Wastes as an Ingredient for

Edible Films Containing Kabog

*Nils Rentsch, Laura Nyström and Joan Oñate Narciso*
