ABSTRACT
Polysaccharides are one of the main components in citrus fruits. A number of polysaccharides have been identied in citrus peel, endocarps, segments, and pulps (Figure 4.1). Most studies on structural polysaccharides in citrus fruits have dealt with the polysaccharides found in the peel, because these cell wall polysaccharides affect the growth, ripening, and storage properties of the fruit. It has been reported that the peel contained about 55 mol% pectic polysaccharides, including homogalacturonan (HG), rhamnogalacturonan I (RG-I), and rhamnogalacturonan II (RG-II)
4.1 Introduction .................................................................................................. 133 4.2 Pectin and Its Modied Products from Citrus .............................................. 136
4.2.1 Citrus Pectin and Its Structure .......................................................... 136 4.2.2 Extraction of Citrus Pectin ............................................................... 140
4.2.2.1 Commercial Preparation of High-Ester Pectin .................. 140 4.2.2.2 Production Process for Low-Ester Pectin .......................... 142 4.2.2.3 Other Extraction Methods ................................................. 142
4.2.3 Modication of Citrus Pectin ........................................................... 143 4.2.4 Health Benets of Citrus Pectin and Modied Citrus Pectin ........... 146
4.2.4.1 Health Benets of Citrus Pectin......................................... 146 4.2.4.2 Health Benets of Modied Citrus Pectin ......................... 148
4.2.5 Use of Citrus Pectin in the Food Industry ........................................ 152 4.2.5.1 Fruit Jelly and Jam ............................................................. 153 4.2.5.2 Beverages ........................................................................... 154 4.2.5.3 Use of Citrus Pectin as a Fat Replacer ............................... 154 4.2.5.4 Use of Citrus Pectin as Edible Films ................................. 155 4.2.5.5 Other Applications and Future Use ................................... 155
4.3 Cellulose ....................................................................................................... 156 4.3.1 Extraction of Citrus Cellulose .......................................................... 157 4.3.2 Health Benets and Applications in Functional Foods .................... 158
4.4 Conclusions ................................................................................................... 158 Acknowledgment ................................................................................................... 159 References .............................................................................................................. 159
together with type I arabinogalactan (AG) and arabinan. It also contained cellulose (22 mol%) and other noncellulosic polysaccharides (14 mol%), including xyloglucans (XGs) (10 mol%), heteromannans (2 mol%), and heteroxylans (2 mol%), although the proportions were different among different species (Prabasari et al. 2011).
