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This study focuses on the impact of different wall materials on the physicochemical properties of microwave-assisted encapsulated anthocyanins from Ipomoea batatas. Using the powder characterization technique, purple sweet potato anthocyanin (PSPAs) powders were analysed for moisture content, water activity, dissolution time, hygroscopicity, color and morphology. PSPAs were produced using different wall materials: maltodextrin (MD), gum arabic (GA) and a combination of gum arabic and maltodextrin (GA + MD) at a 1:1 ratio. Each of the wall materials was homogenized to the core material at a core/wall material ratio of 5 and were microencapsulated by microwave-assisted drying at 1100 W. Results indicated that encapsulated powder with the GA and MD combination presented better quality of powder with the lowest value of moisture content and water activity. With respect to morphology, the microcapsule encapsulated with GA + MD showed several dents in coating surrounding its core material, whereas other encapsulated powders showed small or slight dents entrapped onto the bioactive compound. Colorimetric analysis showed changes in values of L, a*, b*, hue and chroma in the reconstituted powder compared to the initial powder.

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This chapter reviews literature concerning reports on the failure mechanisms that are commonly experienced in the techniques that have been developed to predict life expectancy of polymeric composite materials. It summarizes the main degradation mechanisms in polymeric composite materials, techniques used for estimating the life expectancy of polymers, standards for life prediction, and the properties of cellulose-based polymeric composites. The case study demonstrated the effects of incorporating cellulose derived from several resources to the properties of sand-cement block. The compressive strength of sand-cement block incorporated with bacterial cellulose was evaluated for three different periods. Results showed that bacterial cellulose nanofibers enhance the durability of bricks by increasing their compressive strength up to 27% and reducing the permeability and density of the sand-cement block. In conclusion, accelerated methodology is useful as a potential tool or vehicle for shelf life prediction of composite polymeric materials.