402 Chilled foods processing applications and can range from hours(e.g. heat exchangers)to typically several days or weeks, and in practice is controlled by the application of a ' clean(Dunsmore et al. 1981). Periodic cleans are employed to return the surface-bound soil accumulation to an acceptable base level(plot B, ig. 14.1(b)and are achieved by increasing cleaning time and/or energy input, e.g. higher temperatures, alternative chemicals or manual scrubbing. A typical example of a periodic clean is the week-end clean down or ' bottoming 14.3 Sanitation chemicals In many instances, management view the costs of cleaning and disinfection as the price of the chemicals purchased, primarily because this is the only"invoice that they see. In reality, however, sanitation chemicals are likely to represent approximately only 5% of the true costs, with labour and water costs being the most significant. The purchase of a good quality formulated cleaning product, whilst being initially more expensive, will more than cover its costs by oth the standard of clean and cle Within the sanitation programme it has traditionally been recognised that cleaning is responsible for the removal of not only the soil but also the majority of the microorganisms present Mrozek(1982) showed a reduction in bacterial numbers on surfaces by up to 3 log orders whilst Schmidt and Cremling(1981) described reductions of 2-6 log orders The results of work at CCfrA on the assessment of well constructed and competently undertaken sanitation programmes on food processing equipment in eight chilled food factories is shown in Table 14.1. The results suggest that both cleaning and disinfection are equally responsible for reducing the levels of adhered microorganisms. It is important, therefore, not only to purchase quality cleaning chemicals for their soil removal capabilities but also for their potential for microbial removal Unfortunately no single cleaning agent is able to perform all the functions necessary to facilitate a successful cleaning programme; so a cleaning solution, or detergent, is blended from a range of typical characteristic components urfactants · inorganic alkalis Table 14.1 Arithmetic and log mean bacterial counts on food processing equipment before and after cleaning and after disinfection Before cleaning After cleaning After disinfection Arithmetic mean 867×104 2.5×103 g mean No of observations 3147processing applications and can range from hours (e.g. heat exchangers) to typically several days or weeks, and in practice is controlled by the application of a ‘periodic’ clean (Dunsmore et al. 1981). Periodic cleans are employed to return the surface-bound soil accumulation to an acceptable base level (plot B, Fig. 14.1(b)) and are achieved by increasing cleaning time and/or energy input, e.g. higher temperatures, alternative chemicals or manual scrubbing. A typical example of a periodic clean is the ‘week-end clean down’ or ‘bottoming’. 14.3 Sanitation chemicals In many instances, management view the costs of cleaning and disinfection as the price of the chemicals purchased, primarily because this is the only ‘invoice’ that they see. In reality, however, sanitation chemicals are likely to represent approximately only 5% of the true costs, with labour and water costs being the most significant. The purchase of a good quality formulated cleaning product, whilst being initially more expensive, will more than cover its costs by increasing both the standard of clean and cleaning efficiency. Within the sanitation programme it has traditionally been recognised that cleaning is responsible for the removal of not only the soil but also the majority of the microorganisms present. Mrozek (1982) showed a reduction in bacterial numbers on surfaces by up to 3 log orders whilst Schmidt and Cremling (1981) described reductions of 2–6 log orders. The results of work at CCFRA on the assessment of well constructed and competently undertaken sanitation programmes on food processing equipment in eight chilled food factories is shown in Table 14.1. The results suggest that both cleaning and disinfection are equally responsible for reducing the levels of adhered microorganisms. It is important, therefore, not only to purchase quality cleaning chemicals for their soil removal capabilities but also for their potential for microbial removal. Unfortunately no single cleaning agent is able to perform all the functions necessary to facilitate a successful cleaning programme; so a cleaning solution, or detergent, is blended from a range of typical characteristic components: • water • surfactants • inorganic alkalis Table 14.1 Arithmetic and log mean bacterial counts on food processing equipment before and after cleaning and after disinfection Before cleaning After cleaning After disinfection Arithmetic mean 1.32
106 8.67
104 2.5
103 log mean 3.26 2.35 1.14 No. of observations 498 1090 3147 402 Chilled foods