Science des Aliments et Formulation, Gembloux Agro-Bio Tech, ULiège, Gembloux, Belgium.
J Food Sci. 2021 Feb;86(2):343-356. doi: 10.1111/1750-3841.15589. Epub 2021 Jan 14.
Oleogels and oleogelation routes have been extensively studied in the past decade; however, the industry has not yet implemented this technique due to price, availability, and clean label. The objective of this study was to evaluate the synergism of binary oleogels structured by monoglycerides (MG) and high melting point triacylglycerols (HF) with and without high-intensity ultrasound (HIU) according to their physical properties. MG:HF (0:6, 1:5, 2:4, 3:3, 4:2, 5:1, and 6:0) oleogels were produced by mixing at 70 °C with a stirring of 350 rpm for 5 min, followed by a cooling and storage at 20 °C for 24 hr. A 20-kHz HIU was applied for 10s, 30s, or 10s using three pulses (10sON/10sOFF) during the cooling step via a macro tip (12.7 mm) and 50% amplitude (56 W) in the presence of few -crystals. Samples were evaluated according to their hardness, oil-binding capacity (OBC), microstructure, melting behavior, viscoelasticity, and flow behavior. The best physical properties were found in the MG6:HF0 oleogel, with a hardness of 1.2 N, elasticity of 5.5 kPa, viscosity of 99 Pa⋅s and 99% OBC. These properties were reduced with the decrease of MG in the blend. The sonication did not improve the MG6:HF0, instead it affected its properties negatively. However, sonication showed a positive effect on the blends of MG and HF. The hardness was improved at least threefold and OBC around 20%, these effects were already observed using only 10s sonication. Sonocrystallization induced secondary nucleation and changed the crystalline material only in blends containing HF indicating the better effect of the sonocrystallization on oleogels in the presence of high-melting points triacylglycerols. PRACTICAL APPLICATION: Oleogels are a valuable alternative in food industry to replace trans and reduce saturated fatty acids content in many food products. The combination of a binary structuration and use of high-intensity ultrasound that is a physical green technology will give the food industry information on how to improve the physical properties of oleogels without increasing the amount of oleogelators, giving a future alternative to clean label and sensory claims of oleogels applications.
过去十年中，油凝胶和油凝胶化途径得到了广泛的研究；然而，由于价格、可用性和清洁标签等因素，该行业尚未采用该技术。本研究的目的是评估由单甘油脂（MG）和高熔点三酰基甘油（HF）组成的二元油凝胶在有无高强度超声（HIU）的协同作用，根据其物理性质。MG：HF（0:6、1:5、2:4、3:3、4:2、5:1 和 6:0）油凝胶通过在 70°C 下以 350rpm 的搅拌速度混合 5min 制备，然后冷却并在 20°C 下储存 24hr。在冷却过程中，使用一个宏观探头（12.7mm）施加 20kHz 的 HIU，持续 10s、30s 或 10s，使用三个脉冲（10sON/10sOFF），并在存在少量晶体的情况下使用 50%的振幅（56W）。根据样品的硬度、油结合能力（OBC）、微观结构、熔融行为、粘弹性和流动行为进行评估。在 MG6:HF0 油凝胶中发现了最佳的物理性能，其硬度为 1.2N，弹性为 5.5kPa，粘度为 99Pa·s，OBC 为 99%。这些性质随着混合物中 MG 的减少而降低。超声处理并没有改善 MG6:HF0，反而对其性质产生了负面影响。然而，超声处理对 MG 和 HF 的混合物有积极的影响。硬度提高了至少三倍，OBC 提高了约 20%，仅使用 10s 的超声处理即可观察到这些效果。超声结晶诱导了二次成核，并仅在含有 HF 的混合物中改变了结晶材料，这表明在存在高熔点三酰基甘油的情况下，超声结晶对油凝胶的效果更好。实际应用：油凝胶是食品工业中一种有价值的替代品，可以替代反式脂肪，降低许多食品中饱和脂肪酸的含量。二元结构的组合和高强度超声的使用（一种物理绿色技术）将为食品工业提供信息，说明如何在不增加油凝胶剂用量的情况下改善油凝胶的物理性质，为清洁标签和油凝胶应用的感官要求提供未来的替代方案。
