Application of an electronic nose for determination of pre‐pressing treatment of rapeseed based on the analysis of volatile compounds contained in pressed oil

Abstract

The article presents an attempt to use an electronic nose together with a new three-parameter method for generation of a digital smellprint in order to specify the mode of processing of rapeseed based on the analysis of volatile compounds contained in cold-pressed rapeseed oil. Prior to the pressing process, the seeds were roasted or improperly stored to obtain oil samples with varied technological quality. The quality of pressed oils was evaluated by determination of the acid value. Furthermore, changes in oil colour were assessed with the use of an imaging colorimeter. Volatile compounds were determined with the use of gas chromatography and an electronic nose with a metal oxide semiconductor (MOS) sensor matrix. It was found that the mode of seed pre-treatment before pressing did not change the colour of the oil significantly. However, it influenced the profile of volatile organic compounds and changed their proportions. Ketones represented the largest proportion of volatile compounds determined for roasted samples and those pressed from seeds moistened up to 25% (w.b.). Alcohols dominated in samples moistened up to 10 and 12%, terpenes were the dominant volatile compounds in samples roasted at 140°C, and other volatile compounds dominated in samples moistened up to 10 and 20% (w.b.). In turn, esters and aromatic compounds accounted for the lowest proportion in the analysed samples. The results shown by the electronic nose were correlated with the presence of particular groups of volatile compounds in rapeseed oil.An enose for analysis of rapeseed oil R. Rusinek et al. 2162

Detection and Differentiation of Volatile Compound Profiles in Roasted Coffee Arabica Beans from Different Countries Using an Electronic Nose and GC-MS

“…To date, the maximum sensor response ∆R/R max , i.e., the maximum value of the change in e.g., the resistance of MOS or conducting polymer (CP) sensors, has been most commonly used for generation of smellprints. The authors developed a new method for generation of smellprints based on two additional parameters [15,17]: the time until achievement of the maximum response-the response time T R and the cleaning time T CL , which is the time of removal of molecules from the sensor's active surface, i.e., the time from achievement of the maximum response ∆R/R max to half of its value. The parameters established in the study were dependent on the type of volatile substances contained in the odor profile and the intensity of emissions of compounds.…”

“…In addition to these methods for evaluation of the aroma and chemical composition of biomaterials, electronic nose devices have been increasingly used in recent decades as fast, simple, and non-invasive tools for assessment of the quality of biological products. The dynamic development of the technology of manufacturing electrochemical transducers and techniques for analyses of large data sets has facilitated a wider use of the electronic nose for the analysis of volatile substances in many areas of life [14][15][16]. The term "electronic nose" defines an instrument consisting of a set of chemically sensitive sensors recognizing simple and complex odors and saving the information digitally in the memory of the device [17].…”

Rapid and Non-Destructive Detection of Compression Damage of Yellow Peach Using an Electronic Nose and Chemometrics

“…A new three-parameter method based on the impregnation time, cleaning time, and maximum response was proposed to electronic fingerprints, which could distinguish the rapeseed samples infected with microflora. In another study, this three-parameter method was used to assess the quality of cold-pressed rapeseed oil and then to determine the pre-pressing treatment of rapeseed [22]. The above studies show that e-nose was an efficient, rapid and non-destructive method to analyze the VOCs of samples and to determine the quality of samples.…”

“…The sensor array is the core component of the e-nose system that directly affects its sensitivity and accuracy. Metal oxide sensors are widely used in e-nose systems due to their low cost and high sensitivity [20][21][22]. E-nose has been used to detect the early spoilage and deterioration of blueberries [23], citrus [24], and apple juice [25] as well as the maturity of persimmon [26] and citrus [27].…”

A Versatile Capacitive Sensing Platform for the Assessment of the Composition in Gas Mixtures

“…Many gas sensors have been presented for the detection of low concentrations of volatile organic compounds (e.g., [4]), among which also gas sensor arrays for e.g., food monitoring [5,6]. However, many of these solutions are based on detection principles that are not possible or allowed in calorific gas detection.…”