In this study, a controlled release system of coacervated complexes consisting of lactoferrin (LF) and carboxymethyl tara gum (CMTG) was developed. Zeta potential and turbidity measurements were employed to optimize pH and the LF:CMTG ratio, and the results showed that pH 4.0 and a 5:1 ratio (LF:CMTG) were ideal for complex formation. These conditions promoted the encapsulation of vitamin D3, and the encapsulation efficiency (EE) was determined to be a function of the total concentration of biopolymers (TC%) and the core-to-wall ratio. The results showed that the highest EE (81%) was achieved for a TC of 1% and a ratio of 1:3. The particles had a spherical shape and an average size of 1.2 μm, which was influenced by the TC%. The thermal stability of the vitamin increased after microencapsulation, and Fourier transform infrared spectroscopy (FTIR) demonstrated the presence of biopolymers and vitamins in the microcapsules. The results of the in vitro simulation showed that the microcapsules enabled the vitamin to be released in the intestine with 35% bioaccessibility. Encapsulation of lipophilic bioactive compounds, such as vitamin D3, was achieved through complexes formed between LF and CMTG, which improved the stability and promoted the controlled release of the vitamin during gastrointestinal simulation in vitro.