Plant Extracts Inhibit the Formation of Hydroperoxides and Help Maintain Vitamin E Levels and Omega‐3 Fatty Acids During High Temperature Processing and Storage of Hempseed and Soybean Oils

Abstract

Oxidative stability of hempseed and soybean oils, was evaluated after heating at 180 °C, followed by a subsequent 14‐day storage at 38 °C. Natural plant extracts (Rosemary, Sage, and Thyme) were added to oils, to evaluate the carry‐over stabilizing potential. Heated oils exhibited a relatively faster (P < 0.05) onset of lipid oxidation, as depicted by the analysis of the peroxides and aldehydes formed during the lipid oxidation process, with hempseed oil being more susceptible to lipid oxidation than soybean oil. There were notable losses in ω‐3 PUFA and ω−6‐GLA during storage of heat treated hempseed oil (P < 0.05). Moreover, peroxide values measured from hempseed oil remained low after high‐temperature heating but progressed at a relatively greater rate than that observed in soybean during storage (P < 0.05). The addition of different plant extracts to oils did not prevent oxidation due to heating, but effectively inhibited the generation of hydroperoxides during subsequent storage (P < 0.05). This stabilizing effect was attributed to retention of tocopherols, in particular, γ‐tocopherol. Practical Application This research demonstrates the use of plant extracts like rosemary, sage and thyme, for improving the shelf‐life and nutritional stability of hempseed and soybean oil. We demonstrate the deterioration of fatty acid profiles and vitamin E levels in the oil on heating and subsequent storage, and show the efficacy of using plant extracts in slowing down these deteriorations. This research will be applicable in food industries using or producing oils for use in food during cooking, and also as dressing on already processed food products.

Comparing microfluidics and ultrasonication as formulation methods for developing hempseed oil nanoemulsions for oral delivery applications

“…Palmitic (C16:0), oleic (C18:1), linoleic (C18:2), and α-linolenic (C18:3), acids are the principle unsaturated and saturated fatty acids, respectively present in HSO; which also contained γ -linolenic acid. Previous investigations from our laboratory reported similar proportions of monounsaturated LA in HSO, but in lower quantities 13 . In our present study, we also detected small quantities of stearidonic and eicosenoic acids, also reported by others 14 .…”

“…Based on these previous results, we utilized an ultrasound process and microfluidic technology in this study to produce O/W NEs with hempseed oil (HSO) as the dispersed phase. Hempseed oil derived from Cannabis sativa L. has been shown to have nutritional value due to a notable content and ratio of omega-6 and omega-3 fatty acids, as well as the presence of γ-linolenic acid, stearidonic acid, tocopherols, tocotrienols, carotenes, minerals, β-sitosterols and terpenoids that collectively contribute to oxidative stability 12,13 . Moreover, of particular interest is the presence of non-psychoactive cannabinoid compounds, that include cannabidiolic acid (CBDA) and cannabidiol (CBD) found in HSO 14 .…”

Plant Extracts Containing Saponins Affects the Stability and Biological Activity of Hempseed Oil Emulsion System

“…Approaches such as encapsulating these active substances with a small amount of oil and delivering them via tunable low-oil concentration emulsion systems have been suggested [28,29]. In a previous study [30], we documented the use of plant extracts from rosemary, sage and thyme for inhibiting hydroperoxides and maintaining vitamin E levels in hempseed oil. In this study, we use plant extracts containing saponins from Saponaria officinalis and Quillaja saponaria for stabilization in a low-oil-content hempseed oil emulsion system.…”

Plant-Based (Hemp, Pea and Rice) Protein–Maltodextrin Combinations as Wall Material for Spray-Drying Microencapsulation of Hempseed (Cannabis sativa) Oil

“…One major problem with highly nutritive oils is the formation of oxidative products, which cause generation of undesirable flavors and rancidity [4]. Hempseed oil is more prone to oxidation due to its unsaturated fatty acid content, which could be inhibited by using stabilizers or plant extracts [5]. However, such additives may or may not be desirable for food industry due to labeling requirements and consumer concerns regarding chemical additives.…”