Dairy processing and technology Milk Science International (69) 2016 15 Method for the determination of product losses in dairy processes
The chemical oxygen demand (COD) in the wastewater of the dairy industry is high. A high COD demand has two problems: First, it could
lead to problems with the sewage treatment plant; second, it means a loss of product. It is well-known that approximately 90 % of the
COD load is milk components, but it is difficult to specify how much effluents occur from the different processes. Thus, it is necessary to
develop a method to determine product losses. This paper shows a possibility of determining product losses and provides information on
where, why and how many COD-loaded wastewaters occur. Here, the first rinse water of the cleaning process in a dairy is collected and the
COD is analysed. In relation to the COD of the pure product, one can determine the product loss. The presented method was reproducible
with a variation coefficient of < 3.6 %, except for cream, which had a variation coefficient of approximately 6.5 %. This method allows for
the optimization of processes and the reduction of the COD load of wastewater.
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