This study introduces an innovative approach for the encapsulation and heat-triggered release of natural pigment, paprika oleoresin (PO) as a model pigment, by formulating oleogel-in-hydrogel bigels incorporating candelilla wax (CW). By varying the CW concentrations, the impact on the critical physicochemical properties of bigels was investigated. Increasing CW concentration from 2 to 8% elevated the sol-gel transition temperature (Tg) of the oleogels significantly, ranging from 45.83 ± 0.83 to 61.38 ± 0.51 °C ( < 0.05). Across all CW concentrations, high encapsulation efficiency over 95% was consistently observed. Conversely, reducing CW concentration increased droplet size within the bigels, varying from 13.19 ± 2.97 to 2.97 ± 0.60 μm ( < 0.05). Notably, these bigels exhibited distinct heat-triggered pigment release characteristics. In specific, the amount of released PO decreased with increased CW concentration, resulting in a lower ΔE* value. Correlation analysis highlighted CW's positive correlation with the Tg of the oleogel and bigel lightness, and its negative correlation with droplet size, cumulative pigment release content, release rate constant, redness, yellowness, and ΔE* of the bigel. These results indicate that controlling pigment release through CW-based bigels with thermoresponsive properties can enhance color stability and preserve the integrity of pigment during heat processing. This novel bigel system with heat-triggered release properties holds promise for wider application in the food industry. Overall, it addresses the critical need to stabilize and precisely regulate natural pigment release, which is important for both product quality and consumer satisfaction in the food industry.

中文翻译：

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基于小烛树蜡油凝胶和瓜尔胶水凝胶的新型双凝胶系统的开发和表征，用于热触发释放特性

本研究介绍了一种创新方法，通过配制掺入小烛树蜡 (CW) 的水凝胶大凝胶，对天然色素辣椒油树脂 (PO) 作为模型色素进行封装和热触发释放。通过改变 CW 浓度，研究了对 Bigels 关键物理化学性质的影响。将 CW 浓度从 2% 增加到 8% 显着提高了油凝胶的溶胶-凝胶转变温度 (Tg)，范围从 45.83 ± 0.83 到 61.38 ± 0.51 °C (< 0.05)。在所有 CW 浓度中，一致观察到超过 95% 的高封装效率。相反，降低 CW 浓度会增加双凝胶内的液滴尺寸，从 13.19 ± 2.97 变化到 2.97 ± 0.60 μm ( < 0.05)。值得注意的是，这些大凝胶表现出独特的热触发颜料释放特性。具体而言，释放的 PO 量随着 CW 浓度的增加而减少，导致 ΔE* 值降低。相关分析表明，CW与油凝胶和bigel明度的Tg呈正相关，与油滴尺寸、累积颜料释放含量、释放速率常数、红度、黄度和bigel的ΔE*呈负相关。这些结果表明，通过具有热响应特性的基于 CW 的双凝胶控制颜料释放可以增强颜色稳定性并在热处理过程中保持颜料的完整性。这种具有热触发释放特性的新型双凝胶系统有望在食品工业中得到更广泛的应用。总体而言，它满足了稳定和精确调节天然色素释放的迫切需求，这对于食品行业的产品质量和消费者满意度都很重要。