An increased public knowledge of the health benefits of unsaturated fats has resulted in a surge of different cooking oils. Intense advertising of various oil brands claiming to provide the best dietary recommendations often leaves buyers unclear of what their best choices are. Herein, we describe a research-based project for upper-level undergraduate students, where they can use interdisciplinary concepts in organic chemistry, biochemistry, analytical chemistry, and instrumental analysis to integrate them in a nutrition lab. The experiment was tested over two years in the Instrumental Analysis class, where each student analyzed a liquid oil used for cooking or salad dressings. Ten cooking oils were selected: sunflower, safflower, avocado, sesame, peanut, corn, canola, grapeseed, soybean, and a mixture of sunflower and coconut oils. Six different olive oil products were also compared according to their country of origin, fertilizer used (organic or regular), and type of oil (extra virgin, extra light, 100% pure). The fatty acids (FAs) were first derivatized to their volatile methyl esters (FAMEs) using a microwave-assisted, base-mediated transesterification reaction and then quantified by GC–MS. After pooling the class data, students were exposed to the practical aspects of food analysis while gaining more understanding of their dietary choices.

Growing health awareness has resulted in the increased use of dietary supplements derived from plants and marine sources, leaving consumers unsure of their best options. There were three objectives of the present study. The first was to design and evaluate an efficient derivatization procedure. The second was to perform a comparative analysis of liquid oils and their corresponding capsules of hemp, chia, and flax seeds. The final objective was to determine the fatty acid (FA) composition of six fish oil products and compare it to the one provided on the label. For the FA profiling, we implemented two efficient, one‐step, sustainable methods with high percentage recovery for the synthesis of FA methyl esters (FAME), which use base catalysis and microwave‐assisted heating. Our results found no difference in nutritional value between liquid oils and capsules of the seed supplements, with flaxseed and chia offering a higher, beneficial n‐3:n‐6 ratio compared to hemp oil. Four of the fish oils analyzed contained significantly less eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) than their reported label, and the other two not only agreed with the manufacturers' declaration but were able to fulfill the daily adequate intake (AI) with fewer capsules.