Characterization of Nanoencapsulated Food Ingredients || Confocal laser scanning microscopy (CLSM) of nanoencapsulated food ingredients

摘要： Encapsulation is a process of entrapping bioactive compounds (e.g., antioxidants, antimicrobials, essential fatty acids, probiotics, vitamins, etc.) within a protecting wall material such as lipid-based or biopolymeric carriers. Encapsulation can help to enhance the stability and bioaccessibility as well as controlled release of bioactive materials and mask unwanted properties of encapsulated ingredients. Nanoparticles have a diameter range from 0.1 nm to 1 μm and show great potential to develop new products and applications in food and packaging industries. The performance of nanocarriers formed by encapsulation processes fundamentally depends on various technical aspects such as carrier wall thickness, morphology, and quality. Therefore, measuring and monitoring of coating thickness and morphology of the nanocarriers is an essential process to control the nanoencapsulation procedure. An excessively thick coating layer would lead to delayed release of bioactive materials, increase of coating time, and consequently, encapsulation costs, while an excessively thin capsule would cause interruption in the release and stability of nanoparticles. Spectroscopic and microscopic techniques are important tools for analyzing the morphology, structure, and coating thickness of nanoparticles. Different electron microscopies have been introduced to investigate nano- and micro-carriers. Scanning electronic microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), near-IR spectra, laser-induced breakdown spectroscopy (LIBS), and confocal laser scanning microscopy (CLSM) are some of these light and microscopic methods.