The lactoperoxidase system (LP-system) is an acceptable chemical method
for raw milk preservation, especially in rural areas where
refrigeration facilities are absent to farmers. Milk production in most
African countries is dominated by small-scale traditional production
systems using low yielding local breeds. Therefore, processors who
operate in such situations must rely on small volumes of milk from many
farmers. Application of the LP-system prolongs the shelf life of raw
milk and also encourages grouping of farmers hence facilitating milk
collection by processors. The application of the LP-system is a recent
preservation method for milk in Cameroon whose efficiency has been
proven. Therefore, need arose for further studies on the influence of
this method on milk processing as well as the quality dairy products.
The LP-system was activated by adding 10 ppm sodium thiocyanate and 8.5
ppm sodium percarbonate to fresh milk. Yoghurt and Bambui cheese were
processed separately from treated and untreated (control) milk samples.
Yogurt was produced from both the treated and the control milk samples
at 2%, 3%, 4% and 5% (v/v) culture levels. Yogurt samples were analysed
for acidity, protein content and dry matter content while cheese was
analysed for butterfat and moisture content. Statistical tests were
conducted by Analysis of Variance using the Fisher's test. Simple
organoleptic assessments were conducted to compare yogurt and cheese
from the treated and the control milk. Activation of the LP-system
delayed lactic acid formation in yogurt during incubation and storage
leading to increased energy consumption during processing and an
improved keeping quality during storage. LPsystem treatment reduced the
overall organoleptic quality of yogurt while it improved on that of
Bambui cheese. Dry matter content and fat content of yogurt were not
significantly affected by LP-system treatment (P<0.05). LP-system
treatment did not also affect the moisture and fat content of cheese
but slightly improved on its yield
