Correct identifications are the key to all data on an organism. Fungi cultured or sequenced from a foodstuff may not always be the spoilage agents, and there are potential pit-falls in culturing and molecular identification. Molecular phylogenetics is resulting in major changes in fungal classification, and substantial changes in the rules on naming fungi were agreed in 2011. Different morphs of a single pleomorphic species can no longer have different scientific names, and stability is to be fostered through lists of protected names. The naming of fungi is becoming increasingly fit-for-purpose by taking advantage of the possibilities arising from advances in molecular and digital technologies. A list of the current names of 100 species of spoilage fungi is included.

Shewanella putrefaciens is an important specific spoilage organism (SSO) in seafood under low-temperature storage and can form biofilms on seafood processing-related contact surfaces, which exacerbates seafood spoilage and causes food safety problems. The characterization of and dynamic change in biofilms formed by Shewanella putrefaciens on three seafood processing-related contact surfaces were investigated in this study. An effective strategy to eliminate mature biofilms by acidic electrolysis water (AEW) was provided. Shewanella putrefaciens can form biofilms on glass, stainless steel and polystyrene, which are closely connected with surface properties such as hydrophilicity/hydrophobicity and surface roughness. AEW can be an excellent choice to clean mature biofilms formed by S. putrefaciens. AEW at a concentration of 3 g/L can remove almost all biofilms on the three common food contact materials tested. There is a bactericidal effect on the biofilm, reducing the possibility of secondary contamination. This study will contribute to promoting the application of AEW for controlling biofilms during seafood processing.

Plasma-activated water (PAW) is a novel and promising alternative to traditional food sanitizers. Recently, the inactivation efficacy of PAW has been demonstrated on a wide range of food products against foodborne pathogens, spoilage microorganisms, and harmful chemicals. The effectiveness of PAW relies on various factors related to the plasma generation mechanisms, the target microorganisms, and the food matrix. The inactivation mechanisms of PAW are attributed to the damage of cell integrity and intracellular components by various reactive oxygen and nitrogen species (RONS). Utilization of plasma-activated liquids and hurdle technologies can enhance the inactivation efficacy and diversify the application of this technology. Scaling-up of PAW is still at the very beginning stage and needs further studies before industrial application.

Scarce use of physically based models for simulating foodstuff rehydration is related, inter alia, to difficulties in determining their hydraulic characteristic curve (water content vs. matric potential under equilibrium conditions). Its direct determination is not feasible for foodstuffs as it requires extended contact time with water to reach equilibrium that may cause microbial spoilage, swelling and physical destruction of the sample. To circumvent these difficulties, an alternative indirect method for determining the characteristic curve over the entire water-content range is proposed. It is based on the hypothesis that the end-parts of this curve, the air-entry value and saturated water content for the wet-end and water sorption isotherm for the dry-end, are relatively easily determined. The predicted characteristic curve was successfully verified for a model food material by comparing it with an independently measured values. Then, it was utilized for simulated rehydration by solving the Richards equation.

Although polyvinyl alcohol (PVA) is a promising biodegradable packaging material, it presents some disadvantages for food packaging such as poor ultraviolet (UV) and water vapor barrier properties, low mechanical strength, poor water resistance, and lack of antimicrobial properties. To overcome these limitations, novel PVA/cellulose nanocrystals (CNC)/titanium dioxide (TiO₂) nanocomposites were developed, characterized, and demonstrated for potential food packaging applications. The mechanical strength, water vapor barrier, and UV barrier properties of PVA/CNC/TiO₂ 5 % film (5 wt% TiO₂ in the PVA/CNC matrix with 5 wt% of CNCs) increased by 55.8 %, 45.2 %, and 70,056.8 %, respectively, compared to those of a PVA film. In the antibacterial simulation test, PVA/CNC/TiO₂ 5 % film could limit the growth of microorganisms for 14 days. In packaging tests with fresh garlic, PVA/CNC/TiO₂ films effectively prevented weight loss and spoilage by external influences, indicating the potential of the PVA/CNC/TiO₂ nanocomposites for food-packaging applications.

A study evaluated the kinetics of color changes due to non-enzymatic browning of a constant (buffered) pH lysine-glucose model system during heating in a water activity range of 0.90-0.95. The results indicate that the rate of browning is dependent on temperature and pH, but not on water activity. The implications of these findings are discussed. Theoretical and mathematical treatments of the data are discussed. (wz)

We report on high-internal-phase, oil-in-water Pickering emulsions that are stable against coalescence during storage. Viscous, edible oil (sunflower) was emulsified by combining naturally derived cellulose nanocrystals (CNCs) and a food-grade, biobased cationic surfactant obtained from lauric acid and L-arginine (ethyl lauroyl arginate, LAE). The interactions between CNC and LAE were elucidated by isothermal titration calorimetry (ITC) and supplementary techniques. LAE adsorption on CNC surfaces and its effect on nanoparticle electrostatic stabilization, aggregation state, and emulsifying ability was studied and related to the properties of resultant oil-in-water emulsions. Pickering systems with tunable droplet diameter and stability against oil coalescence during long-term storage were controllably achieved depending on LAE loading. The underlying stabilization mechanism was found to depend on the type of complex formed, the LAE structures adsorbed on the cellulose nanoparticles (as unimer or as adsorbed admicelles), the presence of free LAE in the aqueous phase, and the equivalent alkane number of the oil phase (sunflower and dodecane oils were compared). The results extend the potential of CNC in the formulation of high-quality and edible Pickering emulsions. The functional properties imparted by LAE, a highly effective molecule against food pathogens and spoilage organisms, open new opportunities in food, cosmetics, and pharmaceutical applications, where the presence of CNC plays a critical role in achieving synergistic effects with LAE.

A cardinal model (CM) for the effects of temperature (range: 32–59 °C), pH (range: 5.0–8.5) and water activity (aw) (range: 0.980–0.995) on Bacillus coagulans DSM 1 growth rate was developed in brain heart infusion broth (BHI), using the Bioscreen C method and further validated in selected food products. The estimated values for the cardinal parameters Tmin, Topt, Tmax, pHmin, pHopt, pHmax, awmin and awopt were 23.77 ± 0.19 °C, 52.89 ± 0.01 °C, 59.37 ± 0.07 °C, 4.70 ± 0.02, 6.43 ± 0.02, 8.56 ± 0.01, 0.969 ± 0.0007 and 0.998 ± 0.0011, respectively. The growth behaviour of B. coagulans was studied in five commercial non-refrigerated ready-to-eat food products under static conditions at 53 °C in order to estimate the optimum specific growth rate for each tested food product. The developed models were validated in the five selected food products under four different dynamic temperature profiles by comparing predicted and observed growth behaviour of B. coagulans. The validation results indicated a good performance of the model for all tested products with the overall Bias factor (Bf) and Accuracy factor (Af) estimated at 1.00 and 1.12, respectively. The developed model can be considered an effective tool in predicting B. coagulans growth and spoilage risks of non-refrigerated ready-to-eat food products during distribution and storage.