This study analyzed biofilms composed of Escherichia coli and Staphylococcus aureus on a stainless steel surface, in the presence of food residues (milk and meat exudate), at 25 and 35 °C, with the objective of simulating the real conditions of industrial processing of these foods. The biofilm formed on the surface was determined by quantifying the colonies and scanning electron microscopy. In addition to milk and meat exudate, three different culture media were used, one specific for each bacterium and a common environment for the growth of both bacteria (Mueller Hinton agar, MH). Such conditions were favorable for the biofilm formation of both bacteria, with predominance of the Gram‐negative species in the multispecies biofilm. The food residues favored the formation of the biofilm in both temperatures, especially the meat exudate at 35 °C, when compared to the MH broth. Therefore, substrate and temperature directly influenced the microbial composition of the biofilm. Practical applications This study demonstrates the influence of industrial residue (substrate) on temperature in the composition of a biofilm. As it was evaluated two distinct bacteria, one Gram‐positive and another Gram‐negative, that can be present in several industrial food processing, it can be observed that the substrate and the temperature may favor the development of a species. This fact is extremely relevant so that a correct hygiene process can be applied and it is necessary to know the composition of the biofilm on a certain surface to combat it more effectively.

Some filamentous fungi are able to grow in food and produce toxic metabolites. It occurs mainly in grains, cereals, oilseeds and some by-products. The growth of fungi in a particular food is governed largely by a series of physical and chemical parameters. The production of toxic metabolites is not confined to a single group of molds irrespective of whether they are grouped according to structure, ecology, or phylogenetic relationships. Mycotoxins can be carcinogenic and cause several harmful effects to both human and animal organisms, in addition to generating large economic losses. The major mycotoxins found in food are the aflatoxins, fumonisins, ochratoxins, patulin, zearalenone, and trichothecenes, generally stable at high temperatures and long storage periods. Considering the difficult prevention and control, international organizations for food safety establish safe levels of these toxins in food destined for both human and animal consumption. Good agricultural practices and control of temperature and moisture during storage are factors which contribute significantly to inhibit the production of mycotoxins. The use of some fungistatic products, such as essential oils and antioxidants, as well as physical, mechanical, chemical, or thermal processing, represents important methods to have the concentration of mycotoxins reduced in food.

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The study evaluated the conservation of strawberries treated with crude plant extracts (barbatimão, sibipiruna, guarana, and catuaba) against fungal deterioration and physicochemical characteristics. MIC of 0.125; 0.0156; 0.25 and 0.0312g/mL were found for barbatimão, sibipiruna, guaraná and catuaba, respectively, against B. cinerea. Treated samples showed no fungal deterioration during 11 days. Analyzes of weight loss, soluble solids, titratable acidity, and pH variation were performed. Sibipiruna showed lower values of mass loss, and the greatest occurred for the catuaba extract. Barbatimão did not change soluble solids and stood out with catuaba in the color parameters L and a*. Small changes in pH were observed with time. Soluble solids maintained values between 6.47 o Brix and 9.90 o Brix for catuaba and sibipiruna extracts at zero and six days. Principal component analysis did not show a strong correlation between the variables. The extracts become alternatives for strawberry conservation, increasing conservation and maintaining physicochemical characteristics.