An Electrochemical Impedance Spectroscopy-Based Technique to Identify and Quantify Fermentable Sugars in Pineapple Waste Valorization for Bioethanol Production

Electrochemical Impedance Spectroscopy (EIS) has been used to develop a methodology able to identify and quantify fermentable sugars present in the enzymatic hydrolysis phase of second-generation bioethanol production from pineapple waste. Thus, a low-cost non-destructive system consisting of a stainless double needle electrode associated to an electronic equipment that allows the implementation of EIS was developed. In order to validate the system, different concentrations of glucose, fructose and sucrose were added to the pineapple waste and analyzed both individually and in combination. Next, statistical data treatment enabled the design of specific Artificial Neural Networks-based mathematical models for each one of the studied sugars and their respective combinations. The obtained prediction models are robust and reliable and they are considered statistically valid (CCR% > 93.443%). These results allow us to introduce this EIS-based technique as an easy, fast, non-destructive, and in-situ alternative to the traditional laboratory methods for enzymatic hydrolysis monitoring. Financial support from the Spanish Government and European FEDER funds (MAT2012-38429-C04-04) and FPI-UPV Program are gratefully acknowledged. Conesa Domínguez, C.; García Breijo, E.; Loeff, E.; Seguí Gil, L.; Fito Maupoey, P.; Laguarda Miró, N. (2015). An Electrochemical Impedance Spectroscopy-Based Technique to Identify and Quantify Fermentable Sugars in Pineapple Waste Valorization for Bioethanol Production. Sensors. 15(9):22941-22955. https://doi.org/10.3390/s150922941 FAOSTAT—Food and Agriculture Organization of the United Nations. Statistics Divisionhttp://faostat.fao.org Reinhardt, A., & Rodriguez, L. V. (2009). INDUSTRIAL PROCESSING OF PINEAPPLE â TRENDS AND PERSPECTIVES. Acta Horticulturae, (822), 323-328. doi:10.17660/actahortic.2009.822.40 Ketnawa, S., Chaiwut, P., & Rawdkuen, S. (2012). Pineapple wastes: A potential source for bromelain extraction. Food and Bioproducts Processing, 90(3), 385-391. doi:10.1016/j.fbp.2011.12.006 Nigam, J. (1999). Continuous ethanol production from pineapple cannery waste. Journal of Biotechnology, 72(3), 197-202. doi:10.1016/s0168-1656(99)00106-6 Tanaka, K., Hilary, Z. D., & Ishizaki, A. (1999). Investigation of the utility of pineapple juice and pineapple waste material as low-cost substrate for ethanol fermentation by Zymomonas mobilis. Journal of Bioscience and Bioengineering, 87(5), 642-646. doi:10.1016/s1389-1723(99)80128-5 Ruangviriy