Stobbs Jarvis A, Ghazani Saeed M, Tu Kaiyang, Pensini Erica, Fameau Anne-Laure, Marangoni Alejandro G
Department of Food Science, University of Guelph, Guelph, Ontario N1G2W1, Canada.
Environmental and Earth Sciences Department, Canadian Light Source Inc, Saskatoon, Saskatchewan S7N2V3, Canada.
Cryst Growth Des. 2025 Jun 4;25(12):4621-4635. doi: 10.1021/acs.cgd.5c00575. eCollection 2025 Jun 18.
We report a practical application of using 1,2-dimyristoyl--glycero-3-phosphoethanolamine (DMPE) to temper dark chocolate. Building upon prior research where 1,2-dimyristoyl--glycero-3-phosphocholine (DMPC) was used to direct CB crystallization into the desired Form V polymorph, we investigated whether DMPE could achieve superior results without the structural defects observed with DMPC-tempered chocolate. Chocolate samples containing 0.1 wt % DMPE were prepared and compared to chocolates tempered with DMPC, as well as commercially tempered and statically cooled controls. Small-angle X-ray scattering (SAXS) revealed that the DMPE addition induced the formation of the Form V polymorph, with no detectable amounts of Form IV polymorph, which is often associated with reduced shelf life and fat bloom in chocolate products. Unlike the DMPC-tempered samples, the DMPE chocolate exhibited no blooming or structural defects such as cracks upon prolonged storage. Small-angle neutron scattering (SANS) experiments showed no evidence of micelle formation by DMPE, suggesting a mechanism distinct from that of DMPC. Fourier transform infrared (FTIR) spectroscopy and attenuated total reflectance imaging indicated no significant chemical interactions between DMPE and the main triacylglycerol (TAG) in CB, 1-palmitoyl-2-oleoyl-3-stearoyl--glycerol (POS). We propose that DMPE acts as a unique tempering particle, which facilitates the formation of the stable Form V polymorph and the correct chocolate microstructure through physical interactions with the crystallizing TAGs on its surface. Moreover, DMPE addition also prevents localized material contraction and bloom development due to the absence of induced lattice strain. Crystallization kinetics of the cocoa butter component of chocolate shows an acceleration of crystallization induced by DMPE at 28 °C, relative to both the native refined cocoa butter and the refined cocoa butter containing DMPC. Polarized light micrographs supported this observation. Isolated seed crystals from cocoa butter showed an enrichment in POS and POP in DMPE chocolate, and a characteristic Form V polymorphism for these seeds, in contrast to both native refined cocoa butter and refined cocoa butter with DMPC, where Form IV was identified at the onset of crystallization. The addition of DMPE to chocolate simplifies the tempering process, potentially reducing production costs and energy consumption, and enhancing the quality and stability of the final product, benefiting both artisanal chocolatiers and large-scale manufacturers.
我们报告了使用1,2 - 二肉豆蔻酰 - sn - 甘油 - 3 - 磷酸乙醇胺（DMPE）来调制黑巧克力的实际应用。基于之前使用1,2 - 二肉豆蔻酰 - sn - 甘油 - 3 - 磷酸胆碱（DMPC）将可可脂（CB）结晶引导为所需的V型多晶型的研究，我们研究了DMPE是否能在不出现DMPC调制巧克力所观察到的结构缺陷的情况下取得更好的效果。制备了含有0.1 wt% DMPE的巧克力样品，并与用DMPC调制的巧克力以及商业调制和静态冷却的对照样品进行比较。小角X射线散射（SAXS）表明，添加DMPE诱导形成了V型多晶型，未检测到IV型多晶型，IV型多晶型通常与巧克力产品保质期缩短和起霜有关。与DMPC调制的样品不同，DMPE巧克力在长时间储存后没有出现起霜或诸如裂缝等结构缺陷。小角中子散射（SANS）实验表明没有证据表明DMPE形成了胶束，这表明其机制与DMPC不同。傅里叶变换红外（FTIR）光谱和衰减全反射成像表明DMPE与CB中的主要三酰甘油（TAG），即1 - 棕榈酰 - 2 - 油酰 - 3 - 硬脂酰 - sn - 甘油（POS）之间没有显著的化学相互作用。我们提出DMPE作为一种独特的调制颗粒，通过与在其表面结晶的TAGs进行物理相互作用，促进了稳定的V型多晶型的形成和正确的巧克力微观结构。此外，由于没有诱导晶格应变，添加DMPE还防止了局部材料收缩和起霜的发展。巧克力中可可脂成分的结晶动力学表明，相对于天然精炼可可脂和含有DMPC的精炼可可脂，在28°C时DMPE诱导了结晶加速。偏光显微镜照片支持了这一观察结果。从可可脂中分离出的籽晶在DMPE巧克力中显示出POS和POP的富集，以及这些籽晶的特征性V型多晶型，这与天然精炼可可脂和含有DMPC的精炼可可脂形成对比，在后者中结晶开始时鉴定出IV型。向巧克力中添加DMPE简化了调制过程，有可能降低生产成本和能源消耗，并提高最终产品的质量和稳定性，这对手工巧克力制造商和大规模制造商都有利。
