Chemical analysis of fatty acids and volatile substances of selected types of nuts and seeds

Bachelor of Science Morine Akuro Ndah

Master's thesis

Abstract:

Abstract Lack of comprehensive data on the chemical composition of some nuts and seeds has made proper dietary recommendation difficult. Thus, there is the growing need to understand what this nut offers to individual diets. Additionally, the diversity of nuts and seeds has made it more expedient to explore deep into what makes each nut and seed unique to be able to effectively classify them for use and get the best of what such nuts and seeds offer rather than just eating it for fun. The aim of the work was to analyse the fatty acids and volatile compounds of selected nuts and seeds such as rondelles (Afrostyrax lepidophyllus), Njangsang (Ricinodendron heudelotii), tiger nut Cyperus esculentus), and sacha inchi or caso nuts Plukenetia volubilis) from Cameroon. To achieve this, the Soxhlet Extraction method for the oil extraction was used, while the GC-MS was used for analysis. It was discovered that tiger nuts had 9 fatty acids comprising of Oleic acid (76.19%), Palmitic acid (11.35%), and Stearic acid (8.01%) as the major ones. In addition, sacha inchi peanuts had 7, with mainly Linolenic acid (94.57%). Furthermore, two varieties of njansang were used i.e., njansang (R. heudelotii var. africanum.) and njansang (R. heudelotii var. heudelotii). It was discovered that both varieties are rich in polyunsaturated fatty acids comprising of were Eleostearic acid (51.7-54.83%), Linoleic acid (28.68-32%), and Linolenic acid (10.04%), Stearic acid (7.07%).and Palmitic acid (4.7%). While Rondelles had 14 fatty acids with palmitic acid (57.88%), Lauric acid (19.43%), and Myristic acid (3.89%) For the volatile components, 27 volatile components were identified in tiger nuts,comprising mainly of Benzene, 1-ethyl-2-methyl-1-methyl-3-(1-methylethyl) (24.22%), and γ-terpinene (23.83). Furthermore, 12 in sacha inchi peanut comprising mainly of m-Cymene (43.56%), γ-Terpinene (36.5%). Additionally, njansang (R. heudelotii var. africanum) had 23 with pentanal (29.64%), 2-hexenal (12.19%), 2- heptenal (12.14%), as leading quantities. While (R. heudelotii var. heudelotii) contained 32, with same major compounds as heudelotii var. africanum). Finally, Rondelles had 6 components identified, Bis(methylthiomethyl) disulfide (74.19%), major ones.

Keywords

nuts, seeds, FAME, GC-MS, Soxhlet extraction

Language used: English

Date on which the thesis was submitted / produced: 28. 4. 2024

Thesis defence

• Supervisor: doc. Ing. Klára Urbanová, Ph.D.
• Reader: Pavel Nový, Ph.D.

Czech University of Life Sciences Prague

Faculty of Tropical AgriSciences

Master programme:
Agri-food Systems and Rural Development