Sensor systems, electronic tongues and electronic noses, for the monitoring of biotechnological processes

Abstract

Production of biofuel is based on the conversion by microorganisms of complex organic substrates into the methane or ethanol, which are consequently used as energy sources. Real time monitoring of the fermented media composition is of paramount for the effectiveness of the whole process. However, despite the fact that products worth billions of dollars are produced through fermentation processes annually, analytical instruments used for these processes' monitoring remain relatively primitive. Established laboratory techniques produce exhaustive information about media composition but analysis is often quite time-consuming, expensive, requires skilled personnel and hardly can be automated. Lack of on-line sensors for the fermentation monitoring is commonly stressed in the literature. One of the techniques particularly suitable for this purpose is chemical sensors. Such features as low prices, relatively simple instrumentation, minimal sample preparation and easy automation of measurements make chemical sensors an attractive tool for industrial process control. However, practical use of chemical sensors in complex media is often hindered by their insufficient selectivity. For example, only pH and oxygen probes are routinely used in bio-reactors. One of the emerging approaches permitting to overcome the selectivity problems is the use of systems instead of discrete sensors. Such systems for liquid and gas analysis were named electronic tongues and electronic noses correspondingly. They are capable to perform both quantitative analysis (components' concentrations) and classification or recognition of multicomponent media. This review presents recent achievements in the R&D and applications of electronic tongues and noses to the monitoring of biotechnological processes.

Evaluation of an electronic nose for the early detection of organic overload of anaerobic digesters

“…Already in 2000, the e-nose technology was applied to the monitoring of the anaerobic digestion process [19]. Indeed, e-nose technology is a potential solution to deliver fast information about reactor status to biogas plant operators as this technology is functional for online process monitoring [12,20]. An attempt to monitor pure culture of methanogenic bacteria with an e-nose has already been realized by Brandgård et al [21], which could estimate methanogens growth.…”

On-line monitoring of food fermentation processes using electronic noses and electronic tongues: A review

“…The main features of such applications are summarized in Table 1. Additionally, three interesting reviews on applications of e-nose technologies have recently appeared covering -among others-fermentations in general [12,13] and in brewery in particular [14].…”

“…Moreover, some of them are included in the interesting review devoted to the use of sensor systems for the monitoring of biotechnological process [12].…”

Olive Oil Traceability

“…There are several reviews on the subject of e-nose and e-tongue technology, including reviews on e-noses (Di Giacinto et al, 2010;Wilson and Baietto, 2009), biomimetic/biotechnology e-nose and/or e-tongue sensing systems (Rudnitskaya and Legin, 2008;Ghasemi-Varnamkhasti et al, 2010)], applications for e-noses and e-tongues (Scampicchio et al, 2008), neural networks for e-noses (Lu et al, 2000), pattern recognition techniques (Berrueta et al, 2007); meat quality assessment by e-nose (GhasemiVarnamkhasti et al, 2009) and computational methods for analysis of e-nose data (Jurs et al, 2000). This review will concentrate on the recent literature on applications of e-noses and etongues in the food industry.…”