Risks and new challenges in the food chain: Viral contamination and decontamination from a global perspective, guidelines, and cleaning.

Even during the continuing world pandemic of severe acute respiratory syndrome coronavirus 2 (SARS CoV-2), consumers remain exposed to the risk of getting infected by existing, emerging, or re-emerging foodborne and waterborne viruses. SARS-CoV-2 is different in that it is transmitted directly via the airborne route (droplets and aerosols) or indirect contact (surfaces contaminated with SARS-CoV-2). International food and health organizations and national regulatory bodies have provided guidance to protect individuals active in food premises from potential occupational exposure to SARS-CoV-2, and have recommended chemicals effective in controlling the virus. Additionally, to exclude transmission of foodborne and waterborne viruses, hygiene practices to remove viral contaminants from surfaces are applied in different stages of the food chain (e.g., food plants, food distribution, storage, retail sector, etc.), while new and enhanced measures effective in the control of all types of viruses are under development. This comprehensive review aims to analyze and compare efficacies of existing cleaning practices currently used in the food industry to remove pathogenic viruses from air, nonfood, and food contact surfaces, as well as from food surfaces. In addition, the classification, modes of transmission, and survival of food and waterborne viruses, as well as SARS-CoV-2 will be presented. The international guidelines and national regulations are summarized in terms of virucidal chemical agents and their applications.

New food safety challenges of viral contamination from a global perspective: Conventional, emerging, and novel methods of viral control.

Food- and waterborne viruses, such as human norovirus, hepatitis A virus, hepatitis E virus, rotaviruses, astroviruses, adenoviruses, and enteroviruses, are major contributors to all foodborne illnesses. Their small size, structure, and ability to clump and attach to inanimate surfaces make viruses challenging to reduce or eliminate, especially in the presence of inorganic or organic soils. Besides traditional wet and dry methods of disinfection using chemicals and heat, emerging physical nonthermal decontamination techniques (irradiation, ultraviolet, pulsed light, high hydrostatic pressure, cold atmospheric plasma, and pulsed electric field), novel virucidal surfaces, and bioactive compounds are examined for their potential to inactivate viruses on the surfaces of foods or food contact surfaces (tools, equipment, hands, etc.). Every disinfection technique is discussed based on its efficiency against viruses, specific advantages and disadvantages, and limitations. Structure, genomic organization, and molecular biology of different virus strains are reviewed, as they are key in determining these techniques effectiveness in controlling all or specific foodborne viruses. Selecting suitable viral decontamination techniques requires that their antiviral mechanism of action and ability to reduce virus infectivity must be taken into consideration. Furthermore, details about critical treatments parameters essential to control foodborne viruses in a food production environment are discussed, as they are also determinative in defining best disinfection and hygiene practices preventing viral infection after consuming a food product.

Enrichment of higher molecular weight fractions in inulin.

Inulin (general formulas GFn and Fm, with G = anhydroglucose and F = anhydrofructose) naturally occurs as a homologous series of oligo- and polysaccharides with different chain lengths. For reasons of growing interest in the food and pet food industries, the short chain inulins have to be separated from their long chain analogues because their properties (digestibility, prebiotic activity and health promoting potential, caloric value, sweetening power, water binding capacity, etc.) differ substantially. To study these properties in relation to the number average degree of polymerization (DPn), ultrafiltration, specific crystallization from aqueous solution, and precipitation from solvent/water mixtures were used to enrich native chicory and dahlia inulin in the higher molecular weight fractions. Depending on the membrane module used, the DPn of chicory inulin (DPn = 8.1) and dahlia inulin (DPn = 29) could be increased by ultrafiltration to a maximum value of, respectively, 22 and 43. With crystallization from aqueous solutions (25 degrees C), similar results were obtained but at a much higher yield. Finally, long chain inulin could be precipitated from aqueous solutions in the presence of high concentrations of methanol, ethanol, and acetone. Acetone demonstrated to be the best solvent system to increase the DPn, followed by ethanol and methanol. However, for safety reasons and food purposes, ethanol was evaluated to be the best choice. With ethanol, the DPn could be raised to 25 for chicory inulin and up to 40 for dahlia inulin.