Departament of Food Science, Federal University of Lavras, P.O. Box 3037, 37200-900 Lavras, MG, Brazil.
Biomaterial Engineering, Federal University of Lavras, P.O. Box, 37200-900 Lavras, MG, Brazil.
Food Res Int. 2023 Apr;166:112611. doi: 10.1016/j.foodres.2023.112611. Epub 2023 Feb 17.
Anthocyanins from grape peel extract have several biological properties and can act as a natural colorant and antioxidant agent. However, these compounds are susceptible to degradation by light, oxygen, temperature, and the gastrointestinal tract. Thus, this study produced microstructured lipid microparticles (MLMs) containing anthocyanins by the spray chilling technique and evaluated the particle stability. trans-free fully hydrogenated palm oil (FHPO) and palm oil (PO) were used as encapsulating materials in the ratios 90:10, 80:20, 70:30, 60:40, and 50:50, respectively. The concentration of grape peel extract was 40 % (w/w) in relation to the encapsulating materials. The microparticles were evaluated for thermal behavior by DSC, polymorphism, FTIR, size distribution and particle diameter, bulk density, tapped density, flow properties, morphology, phenolic compounds content, antioxidant capacity, and retention of anthocyanins. Furthermore, the storage stability of the microparticles was investigated at different temperatures (-18, 4, and 25 °C), and the anthocyanins retention capacity, kinetic parameters (half-life time and degradation constant rate), total color difference, and visual aspects were evaluated during 90 days of storage. The resistance of MLMs to the gastrointestinal tract was also evaluated. In general, higher FHPO concentrations increased the thermal resistance of the MLMs and both showed defined peaks of β' and β forms. The FTIR analysis showed that the MLMs preserved the original forms of their constituent materials even after atomization, with interactions between them. The increase in the PO concentration directly affected the increased mean particle diameter, agglomeration, and cohesiveness, as well as lower bulk density, tapped density, and flowability. The retention of anthocyanins in MLMs ranged from 81.5 to 61.3 % and was influenced by the particle size, with a better result observed for the treatment MLM_90:10. The same behavior was observed for the phenolic compounds content (1443.1-1247.2 mg GAE/100 g) and antioxidant capacity (1739.8-1660.6 mg TEAC/100 g). During the storage, MLMs made with FHPO to PO ratios of 80:20, 70:30, and 60:40 showed the highest stability for anthocyanin retention and color changes at the three temperatures (- 18 °C, 4 °C, and 25 °C). The gastrointestinal simulation in vitro revealed that all treatments were resistant to gastric phase and maintained a maximum and controlled release in the intestinal phase, demonstrating that FHPO together with PO are effective to protect anthocyanins during gastric digestion, and can improve the bioavailability of this compound in the human organism. Thus, the spray chilling technique may be a promising alternative for the production of anthocyanins-loaded microstructured lipid microparticles with functional properties for various technological applications.
葡萄皮提取物中的花色苷具有多种生物特性，可用作天然着色剂和抗氧化剂。然而，这些化合物容易受到光、氧、温度和胃肠道的降解。因此，本研究采用喷雾冷却技术制备了含有花色苷的微结构脂质微粒（MLMs），并评价了粒子的稳定性。全反式部分氢化棕榈油（FHPO）和棕榈油（PO）分别以 90:10、80:20、70:30、60:40 和 50:50 的比例作为包封材料。葡萄皮提取物的浓度为 40%（w/w）相对于包封材料。通过 DSC、多晶型、FTIR、粒径分布和粒径、堆积密度、振实密度、流动性能、形态、酚类化合物含量、抗氧化能力和花色苷保留率对微粒子进行评价。此外，还在不同温度（-18、4 和 25°C）下研究了微粒子的储存稳定性，并在 90 天的储存期间评估了花色苷的保留能力、动力学参数（半衰期和降解常数速率）、总色差和外观。还评价了 MLMs 对胃肠道的抵抗力。一般来说，较高的 FHPO 浓度增加了 MLMs 的热稳定性，两者都显示出明确的β'和β形式的峰。FTIR 分析表明，即使在雾化后，MLMs 也能保持其组成材料的原始形式，并相互作用。PO 浓度的增加直接影响平均粒径、团聚和内聚性的增加，以及堆积密度、振实密度和流动性的降低。MLMs 中花色苷的保留率在 81.5%至 61.3%之间，受粒径影响，处理 MLM_90:10 的效果更好。酚类化合物含量（1443.1-1247.2mgGAE/100g）和抗氧化能力（1739.8-1660.6mgTEAC/100g）也表现出相同的行为。在储存过程中，FHPO 与 PO 的比例为 80:20、70:30 和 60:40 的 MLMs 在三种温度（-18°C、4°C 和 25°C）下表现出花色苷保留和颜色变化的最高稳定性。体外胃肠道模拟表明，所有处理均能抵抗胃相，并在肠相中保持最大和控制释放，表明 FHPO 与 PO 一起可有效保护花色苷在胃消化过程中，并能提高该化合物在人体中的生物利用度。因此，喷雾冷却技术可能是一种有前途的方法，可用于生产具有各种技术应用功能特性的花色苷负载微结构脂质微粒。
