## 5 Microencapsulated Bioactive Compounds: Application in Food Systems  
The overall success of microencapsulation in terms of bioactivity or functional effects of the bioactive compounds can only be accessed by using them in real food systems. Sometimes, it is seen that the better encapsulation efficiency does not always result in better bioactivity due to undesirable release kinetics of active ingredients. The characteristics of microcapsules such as higher or optimum encapsulation efficiency, stability, morphology, and molecular interactions between core and wall materials are important, but the actual behavior of these microcapsules in the real food systems must be ensured to draw a conclusion. Thus, after optimizing the microencapsulation process, it is mandatory to ensure that the bioactive compound has its characteristics in real food systems. Antioxidant potential, antimicrobial effect, flavor enhancement, and food stabilization are some important functions of many bioactive compounds which are used for the development of food products (Figure 3). The antioxidant activity of bioactive compounds either in free form or in encapsulated form can be judged by the free radical scavenging activity and DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (3-ethylbenzothazoline-6-sulphonic acid assay), TEAC (Trolox equivalent antioxidant activity), and FRAP (ferric reducing ability of plasma) assays [190, 191, 192]. Total phenolic content also indicates the antioxidant potential of extracts containing natural bioactive compounds. Microbial inhibition tests are conducted to analyze the antimicrobial effect and a critical sensory evaluation is followed for assessing the sensory profile of food products that are being developed using these microcapsules containing bioactive compounds. The release kinetics of natural bioactive compounds, as well as their degradation rate, are also analyzed to see the positive or negative effects of microencapsulation on the active ingredients of these compounds. There are several food industries with potential products for the inclusion of microencapsulated ingredients, including dairy products, meat products, bakery products. and beverages (Table 2). [PERSON] et al. [193] studied the encapsulation of thymol essential oil in sodium caseinate and reported that encapsulated essential oil was more effective than free form (unencapsulated) for inhibiting food-borne pathogens (_Listeria_) in milk. It might be due to enhanced distribution and solubility through encapsulation. [PERSON] et al. [194] encapsulated eug and thymol in zein/casein complex nanoparticles; the authors reported that encapsulated essential oils showed higher bactericidal activity than unencapsulated essential oils. Controlled release of eugenol and thymol was also seen in the encapsulated samples. [PERSON] et al. [195,196] investigated the encapsulation of essential oils in cyclodext to provide long-term effects by increasing their retention, as well as controlling their release in the food matrix. They found higher ABTS scavenging capacity, a reduction in the volatility, and a lesser degradation of essential oil microcapsules during the storage period [196]. [PERSON] et al. [72] encapsulated vitamin B\({}_{12}\) in water-in-oil-in-water double emulsions to produce functional cream for cheese milk standardization. They observed higher encapsulation efficiency (96%) and a lower loss of vitamins during in vitro gastric digestion. The encapsulation of vitamin B\({}_{12}\) in double emulsions also reduced its losses in the whey portion and increased the retention from 6.3 to more than 90% in the cheese samples. The encapsulation of vitamin E using octenyl succinin anhydride modified starches has been carried out by [PERSON] et al. [66]. It was concluded that the capsules could be used in drug and beverage applications. [PERSON] et al. [197] used dextrin for the encapsulation of polyunsaturated fatty acids to control their release and to improve their stability. [PERSON] et al.