Sterilization of food packaging by UV-C irradiation: Is Aspergillus brasiliensis ATCC 16404 the best target microorganism for industrial bio-validations?

In food industries UV-C irradiation is used to achieve decontamination of some packaging devices, such as plastic caps or laminated foils, and of those smooth surfaces that can be directly irradiated. Since its effectiveness can be checked by microbial validation tests, some ascospore-forming molds (Aspergillus hiratsukae, Talaromyces bacillisporus, Aspergillus montevidensis, and Chaetomium globosum) were compared with one of the target microorganisms actually used in industrial bio-validations (Aspergillus brasiliensis ATCC 16404) to find the species most resistant to UV-C. Tests were carried out with an UV-C lamp (irradiance = 127 μW/cm; emission peak = 253.

Effect of peracetic acid on ascospore-forming molds and test microorganisms used for bio-validations of sanitizing processes in food plants.

Industrial sterilization of packaging and filling machineries by peracetic acid (PAA) is a widespread practice. In our study we assessed the resistance to PAA of three ascospore-forming molds (Chaetomium globosum ATCC 6205; Talaromyces bacillisporus SSICA 10915; Aspergillus hiratsukae SSICA 3913) compared to that of Aspergillus brasiliensis ATCC 16404 and Bacillus atrophaeus DSM 675, that are currently used as test microorganisms during industrial bio-validations of food packaging and machineries. Tests were carried out at 40 °C using 1,000 mg/l of PAA, with or without a supporting material (aluminium, tin-plate, PET).

Sanitization of packaging and machineries in the food industry: Effect of hydrogen peroxide on ascospores and conidia of filamentous fungi.

In the food industry, sterilization of packaging and filling machines by hydrogen peroxide (HP) is a widespread practice. Its effectiveness is usually tested by means of inactivation tests on selected test microorganisms that were any case chosen without taking into account that food products could be also spoiled by microorganisms presumably resistant to HP. For this reason, the aim of this work was to assess the resistance of different ascospore-forming moulds (Talaromyces bacillisporus, Aspergillus hiratsukae, Chaetomium globosum) to HP, in order to find the most resistant to this kind of chemical stress, and to compare their resistance with that registered for other moulds, including test microorganism Aspergillus brasiliensis ATCC 16404.

Aspergilli with Neosartorya-type ascospores: heat resistance and effect of sugar concentration on growth and spoilage incidence in berry products.

This study focused on four different heat resistant aspergilli: two strains of Aspergillus hiratsukae (≡Neosartorya hiratsukae), one strain of Aspergillus neoglaber (≡Neosartorya glabra), and one strain of Aspergillus thermomutatus (≡Neosartorya pseudofischeri), all isolated from spoiled pasteurized products. Their heat-resistance, the sugar concentration limiting their germination and growth in berry-based media, and a possible relation between the contamination levels of the raw materials used and the spoilage incidence in strawberry jams were assessed. Heat resistance data obtained from thermal death curves showed that the D values of the strains tested ranged between 3.

Occurrence and ecological distribution of Heat Resistant Moulds Spores (HRMS) in raw materials used by food industry and thermal characterization of two Talaromyces isolates.

In this study, screening of some raw materials used to produce pasteurized products was carried out to determine the occurrence and ecological distribution of heat-resistant fungi. The search for Heat Resistant Mould Spores (HRMS) resulted in the isolation of a limited number of fungal genera: Arthrinium, Aspergillus with either Eurotium-type or Neosartorya-type ascoma, Byssochlamys, Hyphodermella, Monascus, Penicillium, Rasamsonia, Talaromyces and Thermoascus. Sexual aspergilli constituted an overwhelming percentage of the mycobiota, totaling 93.

Monitoring the mycobiota of three plants manufacturing Culatello (a typical Italian meat product).

This study reports the composition of the mycobiota growing on the surface of Culatello (a typical Italian meat product) and occurring in the environments of three processing plants. Samples were collected in both winter and summer. A total of 84 culatelli and 14 samples from the plant environment were examined.

Heat-resistance of Hamigera avellanea and Thermoascus crustaceus isolated from pasteurized acid products.

Products containing sugar or fruit derivatives are usually subjected to a pasteurization process that can anyway be ineffective to kill ascospores from heat-resistant molds. Although the most occurring and economically relevant heat-resistant species belong to Byssochlamys, Neosartorya, Talaromyces, and Eupenicillium genera, an increasing number of uncommon heat-resistant isolates have been recently detected as spoiling microorganisms in such products. Since Hamigera spp.