Sonwai Sopark, Ponprachanuvut Punnee
Department of Food Technology, Faculty of Engineering and Industrial Technology, Silpakorn University.
J Oleo Sci. 2014;63(7):661-9. doi: 10.5650/jos.ess14036. Epub 2014 Jun 11.
Mango kernel fat (MKF) has received attention in recent years due to the resemblance between its characteristics and those of cocoa butter (CB). In this work, fatty acid (FA) composition, physicochemical and thermal properties and crystallization behavior of MKFs obtained from four varieties of Thai mangoes: Keaw-Morakot (KM), Keaw-Sawoey (KS), Nam-Dokmai (ND) and Aok-Rong (AR), were characterized. The fat content of the mango kernels was 6.40, 5.78, 5.73 and 7.74% (dry basis) for KM, KS, ND and AR, respectively. The analysis of FA composition revealed that all four cultivars had oleic and stearic acids as the main FA components with ND and AR exhibiting highest and lowest stearic acid content, respectively. ND had the highest slip melting point and solid fat content (SFC) followed by KS, KM and AR. All fat samples exhibited high SFC at 20℃ and below. They melted slowly as the temperature increased and became complete liquids as the temperature approached 35°C. During static isothermal crystallization at 20°C, ND displayed the highest Avrami rate constant k followed by KS, KM and AR, indicating that the crystallization was fastest for ND and slowest for AR. The Avrami exponent n of all samples ranged from 0.89 to 1.73. The x-ray diffraction analysis showed that all MKFs crystallized into a mixture of pseudo-β', β', sub-β and β structures with β' being the predominant polymorph. Finally, the crystals of the kernel fats from all mango varieties exhibited spherulitic morphology.
近年来,芒果核脂肪(MKF)因其特性与可可脂(CB)相似而受到关注。在本研究中,对从泰国四个芒果品种:Keaw-Morakot(KM)、Keaw-Sawoey(KS)、Nam-Dokmai(ND)和Aok-Rong(AR)中获得的MKF的脂肪酸(FA)组成、物理化学和热性质以及结晶行为进行了表征。KM、KS、ND和AR芒果核的脂肪含量(干基)分别为6.40%、5.78%、5.73%和7.74%。FA组成分析表明,所有四个品种的主要FA成分均为油酸和硬脂酸,其中ND和AR的硬脂酸含量分别最高和最低。ND的滑动熔点和固体脂肪含量(SFC)最高,其次是KS、KM和AR。所有脂肪样品在20℃及以下均表现出较高的SFC。随着温度升高,它们缓慢熔化,当温度接近35℃时完全变成液体。在20℃静态等温结晶过程中,ND的阿弗拉米速率常数k最高,其次是KS、KM和AR,这表明ND的结晶最快,AR最慢。所有样品的阿弗拉米指数n在0.89至1.73之间。X射线衍射分析表明,所有MKF均结晶为假β'、β'、亚β和β结构的混合物,其中β'为主要多晶型物。最后,所有芒果品种核脂肪的晶体均呈现球晶形态。