Carotenoids are potent antioxidants, but they are highly unstable and susceptible during processing and storage. Encapsulation technologies protect against degradation and are capable of releasing individual or combination of bioactive substances during processing as well as development of various functional food products. Moreover, encapsulating agents can be used to increase the stability of carotenoids and form a barrier between the core and wall materials. Suitable encapsulating agents, temperature, and drying methods are the most important factors for the encapsulation process. In this report, we reviewed the current status of encapsulation of carotenoids from different fruits, vegetables, spices, seaweeds, microorganisms, and synthetic sources using various types of encapsulating agents through spray drying and freeze drying. We also focused on the degradation kinetics and various factors that affect the stability and bioavailability of encapsulated carotenoids during their processing and storage.

Consumers currently demand more nutritious food, which is minimally processed and naturally produced. Flavonoids are one of the major plant metabolites found throughout the plant kingdom, especially in fruits and vegetables. Flavonoids exert tremendous positive effects on health and protect against various diseases. Fruits and vegetables are difficult to store for a long period, owing to their perishable nature even at low temperatures. Therefore, processing is necessary to prolong their shelf lives and increase nutritional values. Thermal processing has been used in the food sector since ancient times. However, nonthermal processing has become more attractive to consumers and product developers recently, owing to the retention of beneficial health properties after nonthermal processing. The present review will address the effects of thermal and nonthermal processing methods such as blanching, drying, high-pressure processing, ultrasound, pulsed electric field, and ultraviolet irradiation on total and individual flavonoid content in fruits and vegetables. In addition, this text will elucidate the stability characteristics as well as bioavailability, cytotoxicity, and transformations of flavonoids during thermal and nonthermal treatments.