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. Tests were carried out from 50 to 60 °C on spores or conidia, depending on the strain, either by immersing inoculated strips (aluminium, tin-plate, HDPE, PET) in HP, or by directly inoculating cells in the sanitizing medium. In both tests, T. bacillisporus proved the most resistant strain, followed by A. hiratsukae, C. globosum and A. brasiliensis at all temperatures tested. In test without a supporting material, D values of T. bacillisporus varied from 6 to 23 s. In test with metallic or plastic strips, D values of T. bacillisporus were higher on plastic materials, compared to those obtained on metallic ones up to 53 °C, whereas at higher temperatures D values proved similar. For A. hiratsukae, D values were similar if different materials were compared, except for D50 on aluminium and HDPE, which proved slightly higher (3.1-3.4 s) than those obtained on tin-plate and PET (2.7-2.8 s). Analogously, ascospores of C. globosum behaved in a similar way if different materials were compared, except for D50 values that varied in a wide range (from 2.9 s on tin-plate to 4.0 s on HDPE). A. brasiliensis was rapidly inactivated by the synergistic effect of heat and hydrogen peroxide, so for this strain it was not possible to calculate any D value. Based on the results obtained in this paper, tested ascospore-forming moulds proved to be sensibly more resistant to HP than other heat-sensitive strains tested, their D values always being significantly higher, regardless of the strain considered and the supporting material assessed. Ascospore-forming moulds could be furtherly investigated, as for practical purposes they seemed most suitable as target microorganisms than heat-sensitive microorganisms such as Aspergillus brasiliensis ATCC 16404, their use during bio-validations of sanitizing processes on machineries used for refrigerated products (pH > 4.5) or non-refrigerated acid products (pH ≤ 4.5) leading to more performing results.

中文翻译：

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食品工业中包装和机械的消毒：过氧化氢对丝状真菌的子囊孢子和分生孢子的影响。

在食品工业中，使用过氧化氢（HP）对包装和灌装机进行灭菌是一种普遍的做法。通常通过对选定的测试微生物进行灭活测试来测试其有效性，这些测试微生物在任何情况下都没有考虑到食品也可能会被可能抵抗HP的微生物破坏。因此，这项工作的目的是评估不同的形成孢子的霉菌（Talaromyces bacillisporus，平曲霉，Chaetomium globosum）对HP的抵抗力，以便找到对这种化学胁迫的最强抵抗力，并进行比较它们的抗性与其他霉菌一样，包括测试微生物巴西曲霉ATCC16404。在50至60°C的温度下对孢子或分生孢子进行测试，具体取决于菌株，通过将接种条（铝，马口铁，HDPE，PET）浸入HP中，或将细胞直接接种在消毒介质中。在这两个测试中，在所有测试温度下，芽孢杆菌均显示出最强的抗性，其次为平底曲霉，球孢梭菌和巴西假单胞菌。在不使用支撑材料的测试中，T。bacillisporus的D值从6到23 s不等。在金属条或塑料条的测试中，与在最高53°C的金属条上获得的T. bacillisporus的D值相比，在塑料材料上更高，而在更高的温度下D值被证明是相似的。如果对不同材料进行比较，则对于平头曲霉，D值相似，除了铝和HDPE上的D50值（3.1-3.4 s）略高于马口铁和PET上的D50（2.7-2.8 s）。类似地，C的子囊孢子。如果比较不同的材料，则globosum的行为类似，只是D50值变化范围很大（从镀锡板上的2.9 s到HDPE上的4.0 s）。由于热和过氧化氢的协同作用，巴西巴西杆菌迅速失活，因此对于该菌株，无法计算任何D值。根据本文获得的结果，经测试的形成子孢子的霉菌比其他对热敏感的菌株具有更高的耐HP性，其D值始终显着更高，而与所考虑的应变和评估的支撑材料无关。可以进一步研究形成子囊孢子的霉菌，因为从实际出发，它们似乎比热敏感微生物（如巴西曲霉ATCC 16404，