Vera-Vázquez Francisco, Ramírez-Bribiesca Jacinto Efrén, Cruz-Monterrosa Rosy G, Crosby-Galvan María M, Barcena-Gama José Ricardo, Ramírez Diana Tamara, Mejía-Méndez Jorge L, Vallejo-Hernández Laura H, López-Mena Edgar R
Programa de Ganadería, Colegio de Postgraduados, Km. 36.5, Montecillo, Texcoco 56230, Estado de México, Mexico.
División de Ciencias Biológicas y de la Salud, Departamento de Ciencias de la Alimentación, Universidad Autónoma Metropolitana, Unidad Lerma, Av. Hidalgo Poniente 46, Col. La Estación, Lerma de Villada 52006, Estado de México, Mexico.
Polymers (Basel). 2023 Dec 29;16(1):106. doi: 10.3390/polym16010106.
The pigments consumed in grazing give the milk from dual-purpose cows raised in tropical conditions a yellowish color, affecting the quality and price of the milk. This study aimed to develop an economical method with supplementary pectin to antagonize the availability of carotenes by designing microparticles with shellac and palm oil as a viable alternative to protect pectin degradation against rumen microbes. Three preparations of microparticles based on citrus pectin were synthesized: unprotected (PnP), protected with palm oil (PwP), and protected with palm oil and shellac (PwPL) microparticles. Samples were roughly characterized by spectroscopy and electron microscopy techniques. The effect of PnP, PwP, and PwPL on blood metabolites and physicochemical characteristics of the milk of grazing lactating cows was evaluated through in vivo assays. The release of citrus pectin from microparticles was determined as uronic acids using solutions with distinct pH, whereas its degradation was studied using in situ tests. Results revealed that PnP, PwP, and PwPL are amorphous structures with sizes that range from 60 to 265 nm or 750 to 3570 µm and have surface charges that range from -11.5 to -50.2 mV. Samples exhibited characteristic peaks during FTIR analyses that corresponded to O-H, C=O, and COOCH groups and bands within the UV-vis region that indicated the absorption of pectin. The EDS analysis revealed the presence of carbon, oxygen, or calcium in samples. The release of uronic acids was higher at pH 2-3 with PwPL. The in situ degradability of PnP, PwP, and PwPL was 99, 28.4, and 17.7%, respectively. Moreover, PwPL decreased the blood concentration of glucose, cholesterol, and lactate. In contrast, 100 g of pectin per animal daily during the feed process reduced yellow coloring. In conclusion, designing particles protected with lipids and polymers as shellac is an economical method that resists degradation at pH levels greater than five.
在热带条件下饲养的兼用型奶牛所产牛奶，因采食的色素而呈现淡黄色，这会影响牛奶的品质和价格。本研究旨在开发一种经济的方法，通过设计以虫胶和棕榈油为原料的微粒来补充果胶，以对抗类胡萝卜素的可利用性，作为保护果胶不被瘤胃微生物降解的可行替代方法。合成了三种基于柑橘果胶的微粒制剂：未保护的（PnP）、用棕榈油保护的（PwP）和用棕榈油和虫胶保护的（PwPL）微粒。通过光谱学和电子显微镜技术对样品进行了大致表征。通过体内试验评估了PnP、PwP和PwPL对放牧泌乳奶牛血液代谢物和牛奶理化特性的影响。使用具有不同pH值的溶液将微粒中柑橘果胶的释放量测定为糖醛酸，而其降解则通过原位试验进行研究。结果表明，PnP、PwP和PwPL是无定形结构，尺寸范围为60至265纳米或750至3570微米，表面电荷范围为-11.5至-50.2毫伏。样品在傅里叶变换红外光谱分析中呈现出与O-H、C=O和COOCH基团相对应的特征峰，以及紫外可见区域内表明果胶吸收的谱带。能谱分析表明样品中存在碳、氧或钙。PwPL在pH 2-3时糖醛酸的释放量更高。PnP、PwP和PwPL的原位降解率分别为99%、28.4%和17.7%。此外，PwPL降低了血液中葡萄糖、胆固醇和乳酸的浓度。相比之下，在饲喂过程中每头动物每天摄入100克果胶可减少牛奶的黄色素沉着。总之，设计用脂质和聚合物如虫胶保护的微粒是一种经济的方法，可在pH值大于5时抵抗降解。
