Physicochemical characterization of organogels prepared from menhaden oil or structured lipid with phytosterol blend or sucrose stearate/ascorbyl palmitate blend

Abstract

The purpose of this research was to produce organogels using two different organogelator blends and two different oil substrates and compare their physicochemical properties. A medium-long-medium (MLM)-type structured lipid (SL) containing 37.44 mol% MLM-type triacylglycerols (TAG) was produced by enzymatic modification of menhaden oil with ethyl caprate. Menhaden oil and SL were used as oil substrates to form organogels. One organogel was formed using a phytosterol blend of β-sitosterol and γ-oryzanol (molar ratios of 2 : 1, 1 : 1, and 1 : 2 at 4, 6, and 8% (w/w) in oil), and another was formed with a blend of sucrose stearate (HLB value: 2) and ascorbyl palmitate (SSAP) (molar ratios of 3 : 1, 1 : 1, and 1 : 3 at 8, 10, and 12% (w/w) in oil). Organogels were formed for all ratios except 2 : 1 and 3 : 1 for the phytosterol and SSAP blend, respectively. For both organogels, the 1 : 1 molar ratio was optimal. This ratio produced organogels with higher melting completion temperatures than menhaden oil and SL (13.6 and 14.3 °C). The SSAP blend had higher melting completion temperatures (72.3 and 72.4 °C) than the phytosterol blend (69.2 and 68.4 °C) for organogels formed using menhaden oil and SL, respectively. All 1 : 1 molar ratio blends exhibited β′ polymorphic form with short spacing peaks at 4.20, 3.97, and 3.71 Å. All organogels improved the oxidative stability of the menhaden oil and SL. These organogels have the potential for use as nutraceuticals or health beneficial low saturated fat alternatives to saturated and/or trans-fats.