Validation of process technologies for enhancing the safety of low‐moisture foods: A review

Abstract

The outbreaks linked to foodborne illnesses in low-moisture foods are frequently reported due to the occurrence of pathogenic microorganisms such as Salmonella Spp. Bacillus cereus, Clostridium spp., Cronobacter sakazakii, Escherichia coli, and Staphylococcus aureus. The ability of the pathogens to withstand the dry conditions and to develop resistance to heat is regarded as the major concern for the food industry dealing with low-moisture foods. In this regard, the present review is aimed to discuss the importance and the use of novel thermal and nonthermal technologies such as radiofrequency, steam pasteurization, plasma, and gaseous technologies for decontamination of foodborne pathogens in low-moisture foods and their microbial inactivation mechanisms. The review also summarizes the various sources of contamination and the factors influencing the survival and thermal resistance of pathogenic microorganisms in low-moisture foods. The literature survey indicated that the nonthermal techniques such as CO 2 , highpressure processing, and so on, may not offer effective microbial inactivation in low-moisture foods due to their insufficient moisture content. On the other hand, gases can penetrate deep inside the commodities and pores due to their higher diffusion properties and are regarded to have an advantage over thermal and other nonthermal processes. Further research is required to evaluate newer intervention strategies and combination treatments to enhance the microbial inactivation in low-moisture foods without significantly altering their organoleptic and nutritional quality.

Peanut Butter Food Safety Concerns—Prevalence, Mitigation and Control of Salmonella spp., and Aflatoxins in Peanut Butter

“…outbreaks, Salmonella spp. contamination in low moisture foods, peanut butter, among others, also tops the list of the most problematic and challenging food safety risks [28][29][30][31][32][33]. In the past it was erroneously assumed that peanut butter is not a high-risk food product in terms of microbial contamination [18,19,29].…”

“…Under favourable conditions of temperature, humidity, and pH, Salmonella spp. exhibits great versatility, adapting to different hosts and mediums such as soil and water [33,52]. It is also reported to be capable of undergoing a cyclic lifestyle characterised by passage through a host into the environment and back into a new host after several years [53].…”

“…In food ingredients, pre-exposure of Salmonella spp. to abiotic stressors increases the chances of developing cross-tolerances to several potential future stressors leading to even more virulent cells in the final food product [33]. Pre-exposure to abiotic stressors is common when peanuts are still in the shell during pre-harvest environments, in curing steps, and during roasting [35].…”

“…On the other hand, due to the oiliness of the peanut butter production plants, dry cleaning methods may even be problematic as well. In the absence of other validated non aqueous cleaning methods, for low moisture food plants, wet cleaning is sometimes generally restricted to situations only considered to be essential, in some cases only once a year [33]. There is also the general erroneous assumption that low moisture foods are at low risk of microbial contamination, as such some industrial plants and domestic peanut butter processing equipment may be used for longer periods without stopping for periodic cleaning and sanitizing [29].…”

“…In that case, the cross contamination of batches is highly likely. In the event of any associated foodborne outbreak which then might require the recall of all the associated products since the last date of cleaning of the facility, this can easily lead even to total bankruptcy of the concerned company [33]; such is the complexity of the problem Salmonella spp. contamination in a peanut butter processing plant.…”