Edible coatings and films have been researched for more than three decades due to their ability to be incorporated with different functional ingredients or compounds as an option to maintain the postharvest quality of fruits and vegetables. The aim of this study was to evaluate the effect of three types of chitosan-based (CH) edible coatings obtained from medium and high molecular weight chitosan, containing ascorbic or acetic acid and sea buckthorn or grape seed essential oils on the physical–chemical and microbiological properties of organic strawberries and apple slices during cold storage at 4 °C and 8 °C. Scanning electron microscope images showed both a smooth structure and a fracture and pore structure on strawberry coatings and a dense and smooth structure on the apple slices coatings. Further, the edible coatings managed to reduce the microbial load of yeasts and molds of the coated strawberries during the storage period. Overall, the treatments preserved the ascorbic acid, total polyphenol content, and antioxidant activity for all the tested samples compared to the control sample, throughout the storage period. In addition, the water activity (a_w) of the coated samples presented lower values (0.96–0.98) than the control samples. The obtained results indicate that the developed chitosan-based edible coatings could maintain the postharvest parameters of the tested samples, also leading to their shelf-life prolongation.

The food industry nowadays is facing new challenges in terms of sustainability and health implications of packaging and processing techniques. Due to their desire for new and natural products coupled with changes in lifestyle, consumers are looking for food products that have been less processed but possess longer shelf life and maintain nutritional and sensorial proprieties during storage. These requirements represent real challenges when dealing with highly perishable food products, such as fruits and vegetables. Thus, in recent years, edible coatings have been intensively developed and studied because of their capacity to improve the quality, shelf life, safety, and functionality of the treated products. Edible coatings can be applied through different techniques, like dipping, spraying, or coating, in order to control moisture transfer, gas exchange, or oxidative processes. Furthermore, some functional ingredients can be incorporated into an edible matrix and applied on the surface of foods, thus enhancing safety or even nutritional and sensory attributes. In the case of coated fruits and vegetables, their quality parameters, such as color, firmness, microbial load, decay ratio, weight loss, sensorial attributes, and nutritional parameters, which are very specific to the type of products and their storage conditions, should be carefully monitored. This review attempts to summarize recent studies of different edible coatings (polysaccharides, proteins, lipids, and composites) as carriers of functional ingredients (antimicrobials, texture enhancers, and nutraceuticals) applied on different minimally processed fruits and vegetables, highlighting the coating ingredients, the application methods and the effects on food shelf life and quality.

The preservation of food represents one of the greatest challenges in the food industry. Active packaging materials are obtained through the incorporation of antimicrobial and/or antioxidant compounds in order to improve their functionality. Further, these materials are used for food packaging applications for shelf-life extension and fulfilling consumer demands for minimal processed foods with great quality and safety. The incorporation of antimicrobial peptides, such as nisin, has been studied lately, with a great interest applied to the food industry. Antimicrobials can be incorporated in various matrices such as nanofibers, nanoemulsions, nanoliposomes, or nanoparticles, which are further used for packaging. Despite the widespread application of nisin as an antimicrobial by directly incorporating it into various foods, the use of nisin by incorporating it into food packaging materials is researched at a much smaller scale. The researchers in this field are still in full development, being specific to the type of product studied. The purpose of this study was to present recent results obtained as a result of using nisin as an antimicrobial agent in food packaging materials, with a focus on applications on products of animal origin. The findings showed that nisin incorporated in packaging materials led to a significant reduction in the bacterial load (the total viable count or inoculated strains), maintained product attributes (physical, chemical, and sensorial), and prolonged their shelf-life.

Possible contamination by Staphylococcus aureus of the production environment and of the meat of a canned meat production factory was analysed. A total of 108 samples were taken from nine critical control points, 13 of them were positive for S. aureus. None of the isolates produced enterotoxins. To determine how much time can elapse between can seaming and sterilisation in the autoclave without any risk of enterotoxin production by S. aureus, the growth and enterotoxin production of three enterotoxin A producing strains of S. aureus (one ATCC strain and two field strains) in canned meat before sterilisation was investigated at three different temperatures (37, 20 and 10 °C). Two types of meat were used, one with and one without sodium nitrite. In the canned products, the spiked bacteria spread throughout the meat and reached high levels. Enterotoxin production was shown to start 10 hours after incubation at 37 °C and after 48 h after incubation at 20 °C; the production of enterotoxin was always detected in the transition between the exponential and the stationary growth phase. At 10 °C, the enterotoxin was never detected. The statistical analysis of the data showed that the difference between the two different types of meat was not statistically significant (p value > 0.05). Since it is well known that following heat treatment, staphylococcal enterotoxins, although still active (in in vivo assays), can be undetectable (loss of serological recognition) depending on the food matrix and pH, it is quite difficult to foresee the impact of heat treatment on enterotoxin activity. Therefore, although the bacteria are eliminated, the toxins may remain and cause food poisoning. The significance of the results of this study towards implementing good manufacturing practices and hazard analysis critical control points in a canned meat factory are discussed with reference to the management of pre-retorting steps after seaming.

Foodborne pathogens represent one of the most dangerous threats to public health along the food chain all over the world. Over time, many methods were studied for pathogen inhibition in food, such as the development of novel packaging materials with enhanced properties for microorganisms’ growth inhibition (coatings, films) and the use of emerging technologies, like ultrasound, radio frequency or microwave. The aim of this study was to evaluate the current trends in the food industry for pathogenic microorganisms’ inhibition and food preservation in two directions, namely technology used for food processing and novel packaging materials development. Five technologies were discussed in this study, namely high-voltage atmospheric cold plasma (HVACP), High-Pressure Processing (HPP), microwaves, radio frequency (RF) heating and ultrasound. These technologies proved to be efficient in the reduction of pathogenic microbial loads in different food products. Further, a series of studies were performed, related to novel packaging material development, by using a series of antimicrobial agents such as natural extracts, bacteriocins or antimicrobial nanoparticles. These materials proved to be efficient in the inhibition of a wide range of microorganisms, including Gram-negative and Gram-positive bacteria, fungi and yeasts.

Research background. Recently, consumers have been increasingly interested in highly nutritional and health-promoting products in the form of functional foods that are produced using environmentally friendly processes as part of the circular economy. Therefore, much research has been carried out related to the valorisation of waste generated during the processing of food, especially fruit and vegetables, commonly referred to as by-products. These by-products consist of peels, seeds, stems or pomace, which have been shown to have valuable nutritional properties (high content of polyphenols, vitamins, antioxidants, etc.). Experimental approach. Considering these aspects, the aim of this study is to characterise three types of by-products of apple processing, namely peel, pulp pomace and whole fruit pomace, from a nutritional point of view. The total content of polyphenols, antioxidant activity, ascorbic acid (vitamin C) and phenolic content were determined in nine apple varieties from two harvest years (2020 and 2021) during 9 months of storage. Results and conclusions. The results showed that apple peel had good nutritional properties, in contrast to the pulp or the whole fruit, which are often removed during apple processing. Therefore, the analysed by-products are suitable candidates for application in the food industry for the development of new products enriched with bioactive compounds. Novelty and scientific contribution. In this study, nine varieties of organic apples were analysed and the nutritional parameters were determined. The phenolic compounds of the studied apple by-products were analysed for possible reuse of apple processing waste.