Browsing by Subject "kaasukromatografia"

Indoor gardening is continuously increasing among consumers. Consumers and greenhouse entrepreneurs are looking for ways to optimize growing conditions for their plants to produce high quality and good yield. So far, the effects of LED lights on the plant biomass production and on the composition of volatile aroma compounds have been investigated. However, the effects of different lights on the taste and odor of homegrown herbs is yet to be discovered. The aim of this study was to investigate how different light conditions would affect the composition of compounds that are mainly responsible for the specific flavor of selected model plants. The main goal was to investigate what type of volatile compounds could be obtained in plants grown under different light conditions. The second goal was to investigate how non-volatile saliva soluble compounds could be modified due to the different growing conditions. Coriander and dill were selected as model plants. Coriander is globally utilized herb while dill is one of the most used herbs in the Nordic countries. Due to their strong flavor, both of these herbs divide consumer opinions and therefore investigation of their flavor modification is important. Coriander and dill were grown in domestic smart gardens manufactured by Plantui Oy. Used light conditions included control, green and blue light. Control light composed of a combination of blue, green and red light. Light source was LED lights. The herbs were grown at +22 °C and at humidity of 56.5 %. Used nutrients were ready-made mixtures by Plantui Oy. The composition of artificial saliva was optimized with commercial coriander and dill for the investigation of flavor compounds. Coriander and dill samples were extracted with the developed artificial saliva after which the volatile compounds were analyzed by a combination of gas chromatography and mass spectrometry (GC-MS) and non-volatile compounds by a combination of liquid chromatography and mass spectrometry (LC-MS). Principal component analysis (PCA) was utilized to investigate the composition of volatile compounds while partial least squares-discriminant analysis (PLS-DA) was used to investigate the differences in the non-volatile compounds. Used light conditions altered the chemical composition of herb leaves. Also, light conditions had a visible effect on plant growth. For example, herbs grown in blue light germinated weakly and produced less biomass. The profile of volatile compounds in corianders grown under green and blue light differed from those grown under control light. For dill, the profiles differed only for the samples grown under blue light. Majority of the volatile compounds were components of the essential oils of herbs and compounds that enhance stress tolerance. When looking at saliva soluble non-volatile compounds, coriander grown under blue light was different from the one grown under control light while for dill a difference was observed both under blue and green light. Based on the results, special light recipes can be developed to modify the flavor of coriander and dill. Further research is still needed, especially on the effects of light conditions in plant cell signaling and thereby on the morphological changes in plants and as a consequence on their flavor compounds.