Abstract:

Volatile compounds have an important role in the quality of agricultural products, and are increasingly taken into consideration in plant breeding programmes. Quantifying the levels of specific volatile compounds with biological relevance, as well as metabolomic studies, are essential to understand the diversity and the inheritance of agronomic traits in plants. Therefore, a Master degree in plant breeding should provide students with the competence to use advanced instrumental techniques for breeding programmes aimed at the improvement of quality. In our Master degree in Plant Breeding, several subjects require the support of analytical methods. To optimize the efforts of students during the learning process, it is essential that theoretical lessons are put into practice in practical sessions. Therefore, the knowledge of advanced analytical techniques is of paramount importance for a precise evaluation of the main volatile compounds, which increases the efficiency of breeding programs aimed to the improvement of aroma and flavour of fruits and vegetables. In the present work, we propose the introduction of a practical session in the mandatory subject “Instrumental Techniques”, consisting of the analysis in samples of a breeding programme of the volatile fraction by means of gas chromatography-mass spectrometry (GC-MS) facilities. For this practical lesson, peppers and related species (Capsicum sp.) used in a breeding programme for improving the aroma quality of peppers will be used. These materials show a plethora of aromas and volatile compounds. The lesson is divided into two sessions and includes the different steps of the analysis, including the preparation of the sample and extraction (head space solid phase microextration, HS-SPME), programming the GC temperature regime and obtaining the chromatogram. In the second lesson, chromatogram peaks will be identified by means of MS library and chemical standards. This lesson allows students to acquire the competence for the use of a high-technology chemical analysis system (HS-SPME extraction and GC-MS analysis) as well as to interpret the results and deal with real problems that they can learn how to fix. As a result, with this session our Plant Breeding Master students may enhance their competence for chemical analysis for compounds that are of interest for developing improved cultivars. Moreover this practical session can be adapted to the study and genetic improvement of many other vegetables of fruits, raw or processed, and may be also useful for other students from plant sciences or food technology.

Keywords:

Post-graduate studies, GC-MS, aroma, flavour, fruit quality, practical lessons.