C apsicum fruits as functional ingredients with antimicrobial activity: an emphasis on mechanisms of action.

Capsicum spp. fruits (CFs) are a basic ingredient in the diet and have been used as active ingredients in the pharmaceutical, cosmetic, and food products, due to their antioxidant, anti-inflammatory, antiseptic, and antimicrobial properties. The antimicrobial activity is the most studied property due to its effectiveness against pathogenic species, however, few studies have focused on the mechanisms of action involved. Therefore, this review discusses the effects generated by the CFs compounds on the viability and metabolism of microorganisms, highlighting the mechanisms by which these compounds exert their antimicrobial effects. The information provided shows that CFs are mainly source of capsaicinoids and phenolic compounds responsible for the inhibition of bacteria, yeasts, and fungi, through an increase in the permeabilization of the membrane and cell wall. Also, these compounds show an antiviral effect associated with the inactivation of virus binding proteins, preventing their replication and infection. Despite this, there is still a lack of information about the mechanisms that regulate the interactions between CFs compounds and food-important-microorganisms. Therefore, future research should focus on new antimicrobial compounds from CFs for their subsequent use against novel infectious agents, mainly virus of importance in health such as SARS-CoV-2.

Systematic Review and Meta-analysis: Salmonella spp. prevalence in vegetables and fruits.

In this study, a systematic review and a meta-analysis were conducted to analyse recent worldwide information about the prevalence of Salmonella spp. in vegetables and fruits to estimate the effect of the different processes such as washing, cutting or disinfection, and place of sampling. A systematic search was conducted for articles from 2014 to 2020 published to date regarding prevalence of Salmonella spp. in vegetables and fruits, without excluding material by location, or author. It was possible to determine eight categories for vegetables and fruits in comparison with the meta-analysis which showed five categories due to data availability. Results showed prevalence for Salmonella spp. of 0.1%, 0.2%, 13.7%, 0.1%, and 0% for fruits, leafy vegetables, mixed vegetables related to ready-to-eat salads (RTE), tubercles, and tomatoes, respectively. Moreover, categories such as fruits, tubercles, and tomatoes as associated with different types of preparations and places of sampling (Retail stores, fresh products wholesale, street markets, distribution centers, farms, and processing plants) did not present a significant combined effect on the prevalence of Salmonella spp. Likewise, leafy, and mixed vegetables showed differences associated with a type of processing, where leafy fresh unprocessed vegetables had a significant positive effect on the prevalence of the pathogen regarding the RTE products. These findings may be useful for the construction of a quantitative model of risk assessment as a means to characterize the differences among the sort of vegetable, fruit, type of processing, and place of sampling.

Microencapsulation of Vanilla Oleoresin (V. planifolia Andrews) by Complex Coacervation and Spray Drying: Physicochemical and Microstructural Characterization.

Vanilla is one of the most popular species in the world. Its main compound, vanillin, is responsible for its characteristic aroma and flavor and its antioxidant and biological properties. Vanillin is very unstable in the presence of oxygen, light, and humidity, which complicates its use and preservation. Therefore, to solve this problem, this study aimed to develop vanilla oleoresin microcapsules. Vanilla oleoresin was obtained with supercritical carbon dioxide and microencapsulated by complex coacervation and subsequent spray drying (100 °C/60 °C inlet/outlet temperature). The optimal conditions for the complex coacervation process were 0.34% chitosan, 1.7% gum Arabic, 5.29 pH, and an oleoresin:wall material ratio of 1:2.5. Fourier Transform Infrared Spectroscopy (FT-IR) analysis of the coacervates before and after spray drying revealed the presence of the functional group C=N (associated with carbonyl groups of vanillin and amino groups of chitosan), indicating that microencapsulation by complex coacervation-spray drying was successful. The retention and encapsulation efficiencies were 84.89 ± 1.94% and 69.20 ± 1.79%. The microcapsules obtained from vanilla oleoresin had high vanillin concentration and the presence of other volatile compounds and essential fatty acids. All this improves the aroma and flavor of the product, increasing its consumption and application in various food matrices.