Microbial spore production

These effects are less apparent to the manufacturer than to the end user of the polymer dispersion, but they must not be overlooked. Both the foul odours, particularly from hydrogen sulphide, and the actual presence of microbial spores can have a serious effect on man. Hydrogen sulphide levels in contaminated products have never been shown to reach toxic concentrations but even very small amounts can render a product unsaleable. In both of these examples there are strict guidelines on occupational exposure. In the case of microbial spores, overexposure can lead to respiratory disorders and asthmatic symptoms. 

Firstly the container itself may not be biologically clean. If stored in unsuitable conditions, microorganisms may be present before the product is filled into it. Plastic containers will often attract microbial spores and dusts electrostatically and these can lead to contamination of the product when it is filled into the container. When the container is filled and the lid is applied, condensation may irrigate the lid and form a pool of diluted, under-protected product on the product s surface in which contaminants can grow. It is therefore important that biocide is used that has broad spectrum activity against bacteria, yeast and the mould fungi as well as some degree of headspace protection and is stable in the product for the duration of the product s life. 

Equipment and processes for thermal preservation depend on the physical form ol the food and its pll. Foods having a pH < 4.5 often can be sterilized, for commercial purposes, at or near a temperature of I00°C. Commercial sterility lor these products means lhat the product will not spoil owing to microbial growth as long as the pH remains at or below 4.5 The spores of Bacillus <-oagulans are an important exception. This latter microbe is found in tomato products, and these products are often adjusted lo a pH of 4.0 or lower, or given an additional heal treatment. 

Container Cleanliness of Marketing Product The previous cleanliness of containers filled with the product will depend on their transportation exposure, composition, and storage conditions. Glass containers usually carry at least mold spores of different microorganisms, especially if they are transported in cardboard boxes. Other containers and closures made with aluminum, Teflon, metal, or plastic usually have smooth surfaces and are free from microbial contamination but may contain fibers or insects [45], Some manufacturers receive containers individually wrapped to reduce contamination risks and others use compressed air to clean them. However, the cleanliness of wrapped containers will depend on the provider s guarantee of the manufacturing process and compressed-air equipment may release vapors or oils that have to be tested and validated [6],... 

Environmental scientists have generally defined exposure and health effects on a pollutant-by-pollutant basis. In indoor environments these include multiple air pollutants (i.e., 20-50 different VOCs, including formaldehyde and other aldehydes), microbial products (including spores, cell fragments, viable organisms, and secretion products), and reactive agents such as ozone, fibers, and others. The American Thoracic Society defined six important categories listed in Table 4. 

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