Listeria monocytogenes, a member of the genus Listeria, is widely distributed in agricultural environments, such as soil, manure and water. This organism is a recognized foodborne pathogenic bacterium that causes many diseases, from mild gastroenteritis to severe blood and/or central nervous system infections, as well as abortion in pregnant women. Generally, processed ready-to-eat and cold-stored meat and dairy products are considered high-risk foods for L. monocytogenes infections that cause human illness (listeriosis). However, recently, several listeriosis outbreaks have been linked to fresh produce contamination around the world. Additionally, many studies have detected L. monocytogenes in fresh produce samples and even in some minimally processed vegetables. Thus L. monocytogenes may contaminate fresh produce if present in the growing environment (soil and water). Prevention of biofilm formation is an important control measure to reduce the prevalence and survival of L. monocytogenes in growing environments and on fresh produce. This article specifically focuses on fresh produce–associated listeriosis outbreaks, prevalence in growing environments, contamination levels of fresh produce, and associated fresh produce safety challenges.

Lactobacilli are employed in probiotic food preparations and as feed additives in poultry and livestock, due to health benefits associated with their consumption. The objective of this study was to evaluate and compare the probiotic potential of ten lactobacilli strains isolated from commercial dairy food products and animal rumen contents in New Zealand. Genetic identification of the isolates revealed that all belonged to the genus Lactobacillus, specifically the species L. reuteri, L. rhamnosus and L. plantarum. All isolates did not show any haemolytic behaviour. Isolates of dairy origin showed better tolerance to low pH stress. On the other hand, rumen isolates exhibited a higher tolerance to presence of bile salts. All isolates exhibited resistance to aminoglycoside antibiotics, however most were sensitive to ampicillin. Isolates of rumen origin demonstrated a higher inhibitory effect on Listeria monocytogenes, Enterobacter aerogenes and Salmonella menston. Bacterial adherence of all isolates increased with a decrease in pH. This screening study on lactobacilli isolates has assessed and identified potential probiotic candidates for further evaluation.

A globalized food trade, extensive production and complex supply chains are contributing toward an increased number of microbiological food safety outbreaks. Moreover, the volume of international food trade has increased to become very large. All of these factors are putting pressure on the food companies to meet global demand in order to be competitive. This scenario could force manufacturers to be lenient toward food safety control intentionally, or unintentionally, and result in a major foodborne outbreak that causes health problems and economic loss. The estimated cost of food safety incidents for the economy of the United States is around $7 billion per year which comes from notifying consumers, removing food from shelves, and paying damages as a result of lawsuits. Most other countries similarly have economic losses. Much of these losses represent lost markets, loss of consumer demand, litigation and company closures. Concrete steps are needed to improve safety of foods produced for local or overseas markets to avoid unexpected food scandals and economic losses.

Fresh fruits and vegetables are nutritionally well-recognised as healthy components in diets. The microbiological foodborne outbreaks associated with the consumption of fresh produce have been increasing. Salmonella spp., Escherichia coli O157:H7, Staphylococcus aureus, Campylobacter spp. and Listeria monocytogenes are the most common pathogens that contaminate fresh produce. This review discusses recent foodborne outbreaks linked to fresh produce, factors that affect microbiological contamination and measures that could be adopted to reduce the foodborne illnesses. © 2016 Society of Chemical Industry.

The functional food sector has shown tremendous growth in recent years with the application of probiotic bacteria as "food additives". The utilization of probiotic bacteria in food presents many challenges related to their growth, survival, viability, stability and functionality in food processing, storage and consumption as well as changes of sensory characteristics of probiotic foods. Although dairy foods are currently the most common food carrier to deliver probiotics, an increasing number of non-dairy food matrices exhibit potential for delivery of probiotics. This review provides more recent insight into the emergence of non-dairy probiotics products, the interactions between probiotics and different food matrices and the challenges in developing such products. Some of the technical issues are also reviewed and discussed. These issues include the efficacy of probiotic bacteria in non-chilled, low pH or high water activity foods; the potential loss of bacterial viability, additionally unwanted fermentation and changes of the sensory characteristics of food products which may result in poor microbiological quality and low acceptability to consumers.