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Abstract Background As a natural bioproduct obtained from beekeeping, propolis – with its antimicrobial and antioxidative properties – can be used in food production. Scope and approach This review discusses methods for obtaining propolis extracts (EP), application of propolis in antimicrobial and antioxidative protection of food, and the influence of propolis on the physical, chemical, and sensory properties of food. In addition, the allergenic potential of propolis is presented, together with the legal status of propolis application in food production. Key findings and conclusions In food production, EP are used primarily in ethanol, or water/ethanol, because of its low wax content and high content of bioactive compound. The addition of EP enhances the microbial durability and quality of foods during storage. EP are added directly to foods, or are administered superficially through immersing foods in EP or by applying special EP coats. These procedures reduce pathogen counts or completely eliminate pathogens that are transferred by foods and the saprophytic microbiota of meat, fishes, fruits, vegetables, fruit juices, and milk. Propolis can be used as an antioxidant, particularly in meat and fish products, and can confer protection of the antioxidative properties of fruits and juices during storage. Moreover, it contributes to the physical and chemical properties of food, thereby maintaining the quality of food during storage. A disadvantage of propolis is its unique flavor and aroma, which may negatively alter the sensory properties of foods to which it is added. Highlights • Current strategies for the use of propolis in food technology are presented. • Propolis enhances the microbial durability and quality of foods during storage. • Propolis can be used as an antioxidant in food products. • Propolis contributes to maintaining the physical and chemical properties of food. [ABSTRACT FROM AUTHOR]

Drying is one of the most important steps in processing of edible insects biomass for their potential utilisation in food applications. In this study, the impact of pulsed electric field (PEF) pre-treatment (at E = 1.07 kV/cm and W spec = 5 and 20 kJ/kg) on infrared-assisted air drying kinetics of black soldier fly (Hermetia illucens) and yellow mealworm (Tenebrio molitor) larvae has been evaluated. Moreover, microbial load and physical quality parameters of dried matter have been analyzed. The results show that PEF enhances the kinetics of water evaporation from insects biomass, especially in the range of the moisture ratio (MR) from 1.0 to 0.2. For instance, in the case of having been drying H. illucens larvae for 20 min, MR equalled 0.86, 0.75, and 0.72 for the untreated sample, 5 kJ/kg PEF-treated and 20 kJ/kg PEF-treated one, respectively. The effect of the PEF treatment was less visible in the case of H. illucens larvae and for low MR values. The PEF pre-treatment did not affect the water binding properties of dried insect biomass, regardless of species. However, the PEF pre-treated matter exhibited the same or even higher hygroscopic properties than the untreated ones. The difference in optical properties between untreated and PEF-treated samples was marginal. Nevertheless, for microbial contamination, 20 kJ/kg PEF treatment reduced the total number of microorganisms by 0.5–1.0 log cycle in comparison to the dried matter that had not been pre-treated. Nevertheless, the total number of microorganisms was too high to be feasible for food production purposes which would require additional operations to ensure food safety. The interest in utilisation of insects as an alternative source of macronutrients for food and feed is growing tremendously. Drying is one of the most popular first steps in further processing technology applicable to insect biomass. Since air drying is one of the longest and the most energy consuming unit operation, there is a need to seek alternative methods that can be coupled with pre-treatment to enhance the process kinetics. In this paper, the combination of infrared drying of two species of insects preceded by pulsed electric field treatment has been discussed. • PEF treatment enhanced the IR drying kinetics of both analyzed insects' biomass. • Only PEF at 5 kJ/kg changed some of the water binding properties. • PEF promoted browning for H.ilucens but reduced it for T.molitor IR dried biomass. • PEF treated dried insects exhibited better microbial quality than untreated samples. [ABSTRACT FROM AUTHOR]