Aprovechamiento tecnológico mediante minimización de residuos en la industria cítrica

  1. Macario Legaz, Jose Antonio
Supervised by:
  1. Asunción María Hidalgo Montesinos Director

Defence university: Universidad de Murcia

Fecha de defensa: 24 March 2022

  1. Gerardo León Albert Chair
  2. Elisa Gómez Gómez Secretary
  3. Jaime Lora García Committee member

Type: Thesis


In the Region of Murcia there are numerous industries dedicated to the industrial activity of fruit and vegetable processing. As a consequence of this activity, different types of fractions are generated in the processing of fruits and vegetables, some of which to date are not recoverable/reusable. This is a problem, so there is an interest and concern to achieve a better use of them, as well as the products and by-products they contain, in order to obtain greater economic performance and minimize the costs involved in the management of these residues. Through the use of emerging technologies, or technologies, as innovative elements of the project, a nutritional exploitation has been attempted for these by-products, given that they have high value-added compounds, such as oils, antioxidant agents where we find more than thirty polyphenols making profitable thus its economic value. The global objective of this project is the search for technological solutions aimed at making maximum use of the different fractions that are generated in the processing of fruit and vegetable compounds. These fractions have significant biotechnological potential since once characterized and identified, they can be the starting point for the formulation and preparation of new products. The methodology to be followed entails the identification of each of the different fractions that are likely to be valued, such as concentrated clarified extracts of fruit juice that have a high or low content of sugars and extracts rich in antioxidant agents, where the processes Conventional clarification, aim to eliminate insoluble solids and destroy pectic substances by degrading pectin and starch with specific enzymes, flocculating cloudiness with clarifying agents (bentonite, gelatin and / or silicasol), pectins being the main cause of the turbidity present. Membrane filtration ensures an excellent quality permeate with increased clarity and therefore significant color removal. Once identified and characterized both physicochemically and microbiologically, their stability will be evaluated and a study of shelf life under different storage conditions will be carried out. During this process, the possibility of directly marketing these new products, or their application in different developments (juices, smoothies, fruit compounds, soft drinks, etc.) will be determined. The results obtained show that the membrane technology is capable of perfectly clarifying the by-products from the rinds of the citrus fruits studied, having a useful life of at least one year. In addition, with the application of nanofiltration membranes, monosaccharide sugars can be separated from disaccharides, eliminating all pectin, turbidity and color. For all these reasons, the Doctoral Thesis is perfectly justified, as it contemplates the development of new technological processes that can provide a solution to the different residual fractions that they contain (pulp, sugars, antioxidant agents and vegetable oils, among others), valuing those compounds by giving them an outlet in new formulations and preparations, since otherwise they would have to be disposed of as waste. The valuation of the different fractions not only has repercussions in improving the profitability of the fruit and vegetable processing industries, but also, this type of action based on the full use of fruits and vegetables helps to reduce environmental pollution, through the minimization of the different residues. This action aims to provide a broader vision of the technological possibilities for the use of this waste and its possible transformation into high value-added products.