Properties of Wax-Hempseed Oil Oleogels and Their Use for Margarines

Abstract

Hempseed oil (HSO) has many health benefits due to a high content of polyunsaturated fatty acids and many phytochemicals including antioxidants such as tocopherols, polyphenols, and squalene. Several previous studies reported that hemp seed oil contained higher concentrations of tocopherols, flavonoids and phenolics and had higher antioxidant activity than other vegetable oils. Vegetable oil-based oleogels have drawn great interest as alternatives to solid fats used in many food products. In this study, HSO oleogels were prepared using sunflower wax (SW), rice bran wax (RBW), beeswax, and candelilla wax. Properties of the oleogels were examined for firmness, crystal structures, and melting profiles, and were compared with refined soybean oil (SBO) oleogels. HSO oleogels except for RBW-HSO oleogels had lower firmness and weaker crystal network than SBO oleogels. RBW-HSO oleogels had similar firmness and crystal network, and higher melting and crystallization enthalpies than SBO oleogels. To understand the effect of polar compounds, polar compounds were removed from HSO, and oleogels were prepared and examined under the same conditions. Oleogels from HSO without polar compounds had greater firmness, higher melting and crystallization enthalpies, and stronger crystal network waxes than the original oleogels, except for RBW oleogels. It was concluded that, in general, polar compounds negatively affected the physical properties of wax-HSO oleogels. SW- and RBW-HSO oleogels, which had the highest firmness, were incorporated into a margarine formulation. Firmness and melting properties of these margarines were examined. In comparison with commercial spreads and margarines, 3% wax-HSO margarines had greater firmness than commercial spreads while the firmness of stick margarines could not be achieved even with 7% wax. Although further studies are needed to improve their properties, this study showed that wax-HSO oleogels have high potential as solid fat replacements in margarines and spreads.