**3.5 Major milk quality related constraints**

Milk quality related constraints ranked during group discussions with dairy cooperatives are presented in Table 2. The major milk quality related constrains include: limited


Table 2. Major milk quality related problems ranked using pair-wise comparison during group discussions

Microbial Properties of Ethiopian Marketed Milk and Milk Products and

**4.2 Microbial properties of milk and milk products** 

different parts of the country are briefly summarized below.

TBC: Total Bacterial Count; YMC: Yeast and Mould Count

can be partly explained by lactic acid bacteria.

further storage (Gonfa *et al.*, 2001).

into the milk.

Associated Critical Points of Contamination: An Epidemiological Perspective 307

same samples that ranged from the lowest 5.46 to the highest 6.14 with an overall mean value of 5.87. The relatively low pH of *Ergo*, ranging from 4.3 to 4.5 retards the growth of undesirable microorganisms, such as pathogens and spoilage bacteria, and enables its

The microbial content of milk indicates the hygienic levels during milking that include cleanliness of the milking utensils, proper storage and transport as well as the wholesomeness of the udder of the individual cow (Spreer, 1998). The most commonly used microbial quality tests for milk and milk products include determination of total bacterial count (TBC) or standard plate count (SPC) and colifom count (CC). Estimation of yeast and mould counts is also useful for evaluating sanitary practices (O'Connor, 1994). Microorganisms can enter milk via the cow, air, feeds, milk handling equipment and the milker. Once they get into the milk their numbers increase rapidly. It is therefore more effective to exclude microorganisms than trying to control their growth once they get access

There are varieties of traditionally fermented dairy products in Ethiopia, for which the exact type of desirable lactic acid bacteria responsible for fermentation is unknown due mainly to uncontrolled and spontaneous fermentation. Most of these products are produced by smallholder producers where access to the required dairy infrastructure is limited. Results of the present study and selected reports of relevant earlier research efforts on the microbial properties of locally produced milk and milk products that have been carried out in

**Source No of Obs. TBC** *Enterobacteriaceae* **Coliform YMC**  Overall mean 630 8.35 5.10 4.53 8.32 Whole milk 135 9.10 5.49 4.58 - Ergo 105 9.49 4.95 4.51 8.38 Butter 105 6.67 4.95 4.58 8.32 Arera 75 9.35 4.94 4.65 - Ayib 105 7.01 4.84 4.42 8.26 Skim milk 105 9.37 5.34 4.44 -

Table 3. Overall bacterial and yeast and mould counts (log10) per ml/g of milk and milk

Although there are slight variations between sample sources (locations/producer groups) in microbial counts, the figures observed in the present study are generally much higher than acceptable limits (Table 3). TBC is generally high in samples of whole milk, *Ergo* and skim milk. Counts of *Enterobacteriaceae* and coliform counts are higher than acceptable limits: *Enterobacteriaceae* <1 and coliform <10 cfu/ml for pasteurized milk, and coliform <100 cfu/ml for raw milk intended for direct consumption (Council Directives 92/46/EEC, 1992). The higher count in milk indicates substandard hygienic conditions practiced during production and subsequent handling. The high count in fermented milk products, however,

product samples collected from different sources (sites and producer groups)

awareness on hygienic handling of milk and milk products, which could mainly be attributed to inefficient extension services; shortage of capital to purchase recommended equipment (milk containers, and processing and packaging materials); lack of clean water for sanitation purpose and poor condition of barn or milking area that is directly related to shortage of capital and limited awareness of its implication on milk quality.
