Calumba Kriza Faye, Zhong Qixin
Department of Food Science, University of Tennessee, Knoxville, TN, USA; Department of Food Science and Chemistry, University of the Philippines Mindanao, Philippines.
Department of Food Science, University of Tennessee, Knoxville, TN, USA.
Int J Biol Macromol. 2025 Sep;321(Pt 2):146358. doi: 10.1016/j.ijbiomac.2025.146358. Epub 2025 Jul 28.
Shellac is an enteric material with potential to deliver probiotics to the colon. This study explored shellac-based microgels to entrap Lactobacillus bulgaricus ATCC 11842, a probiotic strain used in the food industry but undetectable after simulated digestion. Dispersions with one, two, or all of shellac (5.0 % w/v), zein (2.0 % w/v), and sodium alginate (1.0 % w/v) were prepared at pH 7.7, mixed with probiotics, and sprayed to 2.5 % w/v calcium chloride at pH 3.0, 4.5, or 6.0 to form microgels. Wet microcapsules were collected by centrifugation and characterized for size, microstructure, FTIR spectra, and cell viability during simulated digestion and storage. Irregularly shaped microcapsules had a volume-weighted mean diameter of 84-354 μm. FTIR spectra revealed hydrogen bonding, electrostatic, and hydrophobic interactions in microcapsule formation. Similar viable cell density (7.08-9.40 log CFU/g) but different mass yield was obtained, with entrapment efficiencies of 42.1-112.6 % at pH 3.0, 46.2-95.3 % at pH 4.5, and 45.6-97.6 % at pH 6.0. The reduction was below 2 log CFU/g during 21-day storage at 4 °C and pH 4.5. However, only shellac-zein, shellac-zein-alginate, and shellac-alginate microcapsules fabricated at pH 4.5 had at least 5 log CFU/g viable cells after simulated digestion. This work supports shellac-based probiotic delivery in functional foods.
虫胶是一种肠溶材料，有潜力将益生菌递送至结肠。本研究探索了基于虫胶的微凝胶以包埋保加利亚乳杆菌ATCC 11842，这是一种食品工业中使用的益生菌菌株，但在模拟消化后无法检测到。在pH 7.7下制备含有虫胶（5.0% w/v）、玉米醇溶蛋白（2.0% w/v）和海藻酸钠（1.0% w/v）中的一种、两种或全部的分散体，与益生菌混合，并在pH 3.0、4.5或6.0下喷入2.5% w/v的氯化钙中以形成微凝胶。通过离心收集湿微胶囊，并对其在模拟消化和储存过程中的尺寸、微观结构、傅里叶变换红外光谱（FTIR）和细胞活力进行表征。不规则形状的微胶囊体积加权平均直径为84 - 354μm。FTIR光谱揭示了微胶囊形成过程中的氢键、静电和疏水相互作用。获得了相似的活细胞密度（7.08 - 9.40 log CFU/g）但不同的质量产率，在pH 3.0下包封效率为42.1 - 112.6%，在pH 4.5下为46.2 - 95.3%，在pH 6.0下为45.6 - 97.6%。在4°C和pH 4.5下储存21天期间，活菌数减少低于2 log CFU/g。然而，只有在pH 4.5下制备的虫胶-玉米醇溶蛋白、虫胶-玉米醇溶蛋白-海藻酸盐和虫胶-海藻酸盐微胶囊在模拟消化后具有至少5 log CFU/g的活细胞。这项工作支持了在功能性食品中基于虫胶的益生菌递送。
