Cold plasma treatment is a promising intervention in food processing to boost product safety and extend the shelf‐life. The activated chemical species of cold plasma can act rapidly against micro‐organisms at ambient temperatures without leaving any known chemical residues. This review presents an overview of the action of cold plasma against molds and mycotoxins, the underlying mechanisms, and applications for ensuring food safety and quality. The cold plasma species act on multiple sites of a fungal cell resulting in loss of function and structure, and ultimately cell death. Likewise, the species cause chemical breakdown of mycotoxins through various pathways resulting in degradation products that are known to be less toxic. We argue that the preliminary reports from cold plasma research point at good potential of plasma for shelf‐life extension and quality retention of foods. Some of the notable food sectors which could benefit from antimycotic and antimycotoxin efficacy of cold plasma include, the fresh produce, food grains, nuts, spices, herbs, dried meat and fish industries.

Understanding of the amorphous glassy state of food systems is often crucial in determining physicochemical characteristics and predicting stability of dehydrated and frozen foods. At the glass transition temperature (T g ) of food components, transformation from the amorphous glassy state to the liquid-like rubbery state occurs. T g and ice-melting temperatures (T m ) of food systems are used to construct their state diagrams, in which the different physical states/phases and state/phase transitions of food components are presented in relation to temperature and concentration. A state diagram may be used to identify the appropriate processing and storage conditions of food systems. An overview of determination methods is carried out for glass transition temperature, ice-melting temperature and conditions of maximum-freeze-concentration (glass transition temperature of maximum-freeze-concentrated solution, T g 0 and onset of ice-melting temperature, T m 0 ) for food systems. The data as T g , T m , T g 0 and T m 0 are necessary for construction of state diagrams of foods. The advantages and limitations of the determination methods are discussed. Combined data for glass transition temperature, ice-melting temperature and conditions of maximum-freeze concentration for selected food systems are presented in this study. The effect of food composition on glass line, freezing/melting curve and maximum-freezeconcentration conditions is evaluated. The significance of the state diagrams in predicting the physical, chemical and microbial stability in foods is briefly examined. Glass transition concept and state diagrams are useful for describing the physical and structural stability of food systems at specific conditions, yet they are not considered as the only determining factors of chemical, biochemical and microbial stability of food systems.

A number of recent outbreaks related to pathogens in low-moisture foods have created urgency for studies to understand the possible causes and identify potential treatments to improve low-moisture food safety. Thermal processing holds the potential to eliminate pathogens such as Salmonella in low-moisture foods. Water activity (a w ) has been recognized as one of the primary factors influencing the thermal resistance of pathogens in low-moisture foods. But most of the reported studies relate thermal resistance of pathogens to a w of low-moisture foods at room temperature. Water activity is a thermodynamic property that varies significantly with temperature and the direction of variation is dependent on the product component. Accurate methods to determine a w at elevated temperatures are needed in related research activities and industrial operations. Adequate design of commercial thermal treatments to control target pathogens in low-moisture products requires knowledge on how a w values change in different foods at elevated temperatures. This paper presents an overview of the factors influencing the thermal resistance of pathogens in low-moisture foods. This review focuses on understanding the influence of water activity and its variation at thermal processing temperature on thermal resistance of pathogens in different low-moisture matrices. It also discusses the research needs to relate thermal resistance of foodborne pathogens to a w value in those foods at elevated temperatures.

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