Enrichment of Argan [Argania spinosa (L.) Skeels] Oil with Saffron (Crocus sativus L.) Stigma Powder and Induced Changes in Oil Quality Attributes

Abstract

Argan oil (AO) is a globally reputed vegetable oil thanks to its nutritional and cosmetic value. AO oxidation induces changes that result in a low quality. In this research, we aimed at fortifying AO using saffron stigmas powder (SSP) and assessing its quality. Dried and grounded saffron stigmas were added to AO at three different concentrations (0.2, 0.5, and 1%). All enriched AOs were stored for six consecutive months under two conditions, namely, light and darkness. Quality indices including free fatty acids (FFA), peroxide value (PV), and specific extinction coefficients K232 and K270 as well as profiling of fatty acids, sterols, and tocopherols were monitored on a monthly basis. Our outcomes reveal that the addition of SSP improved AO oxidation parameters by significantly decreasing ( <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" id="M1"> <a:mi>p</a:mi> <a:mo>&lt;</a:mo> <a:mn>0.05</a:mn> </a:math> ) FFA, PV, K232, and K270 of enriched AO (EAO) as compared to unenriched AO (UAO) especially when AO samples are stored in darkness. Such decrease of oxidation parameters was SSP dose-dependent as a general trend. However, AO enrichment did not induce significant changes ( <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" id="M2"> <c:mi>p</c:mi> <c:mo>&lt;</c:mo> <c:mn>0.05</c:mn> </c:math> ) in fatty acid and sterol profiles. Furthermore, the quality parameter values of EAO and UAO did not exceed the limits set by the Moroccan standard throughout the storage period. Sensory analysis results indicate that EAO showed a low rancidity but high scores of saffron smell, flavor, and color as compared to UAO especially with SSP 1%. In conclusion, AO enrichment using SSP could be used to improve AO oxidative stability and its nutritional value.