Agroindustrial Wastes as Sources of Extraction

The Coloqmthoides variety of CitruIIus lanatus (an ancestor of the watermelon) is mainly grown in Eg) ) . The economic importance of this crop is owing to its seeds, and the rest of the fruit is discarded. For this reason, the waste of CitruUus lanatus var. Colocynthoides as a new source of pectin was proposed [42]. For the extraction, HCl was used at different pH values and temperatures, and it was found that at pH 2 and 85°C the highest yield of 19.75% (w/w) was reached. The degree of esterification determined was -55%. With these results, it is stated that this residue may be a potential source of pectin, but more research is needed to fully understand this source of production. 

Masmoudi et al., in 2014, used more than one agroindustrial residue in a extraction process [59]. They used poor-quality dates 

Three different varieties of Papaya peels (Cor/co papaya L.) were analyzed as a source of pectin wild variety, a domesticated variety, and the Solo variety [43]. Papaya peels are discarded into the environment, causing organic pollution. Sometimes it is used as animal feed, not receiving any treatment or use. The results indicated that pectins of both varieties had a low grade of esterification and high molecular weight Although pectins were characterized structurally, functionality studies are needed in order to consider their optimal application within food systems. 

Industrial wastes have been evaluated outside the food industry. In 2013, pectin from sisal Agave sisaiana) waste [85] was extracted. Sisal is widely used for the production of hard fibers. Through an aqueous extraction, yields were obtained in the range of 4.61% to 19.2%, these values are above some other noncommercial sources of pectin as sunflower heads, banana peel, and mango peel. Pectin isolated had a 50% DE. The environment-friendly extraction method and the quite acceptable yield values provide an option to consider for handling and utilization of sisal wastes. 

The diverse plant material sources, and feasible extraction methods available, ranging from physical and to environment- 

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