How can agricultural resources be better revaluated?

Last Friday, July 21st, was held in the conference room of the Higher Technical School of Agronomic Engineering and the Natural Environment (ETSIAMN) of the Universitat Polit?cnica de Val?ncia??(UPV), the reading of the PhD thesis in Science, Technology and Food Management of our colleague Claudia Conesa Dom?nguez; the result, outstanding Cum Laude. The thesis, titled "Technological developments for the improvement and control of the process of obtaining bioethanol from agro-food waste", was directed by the professors Dr. Pedro Fito Maupoey, Dr. Nicol?s Laguarda Mir? and Dr. Luc?a Segu? Gil. The members of the panel were Dr. Fidel Toldr? of the Instituto de Agroqu?mica y Tecnolog?a de Alimentos?(IATA - CSIC, Valencia), Dr. Daniel V?zquez of the Instituto Nacional de Tecnolog?a Agropecuaria?(INTA - Concordia, Argentina) and Dr. Urszula Tylewicz of the?Universit? di Bologna (Cesena, Italy). In addition, it was the occasion, through a clear presentation, to deepen the use of agricultural waste and the control of the processes of obtaining bioethanol by electrochemical techniques. One of the species that has worked on was an example of tropical pineapple, which generates abundant waste during the process of industrialization, and another one, a crop with a lot of local importance, persimmon. Here is the summary of the thesis and the results:As stated by the United Nations Department of Economic and Social Affairs, the first half of the present century will experience a significant increase in global energy demand due to the expected growth of world population and global economic development. On the other hand, recent reports from the Intergovernmental Panel on Climate Change definitely evidence the link between the continued use of fossil fuels and the increasing concentration of greenhouse gases into the atmosphere being responsible for climate change. In this context, a global commitment is needed in the search for cleaner, environmentally friendly and sustainable energy sources, such as second-generation bioethanol from agro-industrial waste. Thus, this PhD Thesis aims to advance in the agro-industrial waste recovery of fruits such as pineapple and persimmon. Specifically, different strategies for enhancing the bioethanol production process were evaluated. Additionally on-line monitoring of the saccharification step and final alcohol content in the studied wastes were taken into consideration. Thus, different technologies were studied to improve the enzymatic hydrolysis performance in pineapple waste. First, hydrolytic performances of commercial enzymes produced by the filamentous fungi?Aspergillus niger?and?Trichoderma reesei?were compared. Next, the use of microwave pretreatments, alone or combined with an alkali treatment, was evaluated to improve the saccharification performance. On the other hand, ?Rojo Brillante? persimmon waste was studied as a potential source of high added value products. Finally, electrochemical impedance spectroscopy based techniques were evaluated for monitoring saccharification and quantifying ethanol in pineapple waste. Results showed that?A. niger?cellulase is an effective alternative to that obtained from?T. reesei?for the saccharification of industrial pineapple waste, especially when combined with hemicellulase. On the other hand, microwave pretreatments at appropriate power and exposure times significantly improved the enzymatic hydrolysis performance. This improvement was particularly remarkable when microwaves were combined with an alkali treatment. On the other hand, industrial persimmon waste was shown to be a low-cost source of bioethanol and antioxidant compounds, mainly carotenoids. Finally, electrochemical impedance spectroscopy was validated as an easy, fast, non-destructive, inexpensive and alternative methodology to the traditional laboratory ones for monitoring saccharification and fermentation processes. This validation was achieved by combining impedance spectroscopy with mathematical models based on artificial neural networks, being robust, reliable, adaptive and easily implementable in electronic systems. To conclude, the present PhD Thesis has provided substantial progress towards agro-industrial waste recovery processes. In fact, several technological developments have been implemented in order to increase the saccharification yield in pineapple waste. Moreover, high added value products have been obtained from persimmon residue. Likewise, these processes can be accurately controlled on-line by electrochemical impedance spectroscopy based techniques combined with specific mathematical models,? representing a significant advance in this field. ? Pictures1 -?Claudia Conesa?during the reading of ther PhD thesis2 - Few of the reading assistants3 - SPE3 Team of Valencia; on the right hand side,?Mar?a Rodr?guez?(Biblioteca de Horticultura) and?Alicia Namesny?on the left hand side?(Poscosecha).