Abstract:
Cow's milk is widely recognized as a vital source of nutrients and is
consumed by millions of people globally in various forms. However, in Sri
Lanka, there is a notable lack of comprehensive databases regarding milk
quality at the grassroots level, particularly concerning regional variations.
This study aimed to evaluate the quality parameters of raw milk collected
from fifty selected chilling centres across the Uva, North Western, North
Central, Eastern, and Central Provinces of Sri Lanka. Collected milk samples
were analyzed for fat content, solid non-fat (SNF) content, lactose content,
protein content, added water, freezing point, corrected lactometer reading,
pH, keeping quality (KQ), solubility index, and alcohol precipitation test to
determine the quality of incoming raw milk across different regions, which is
essential for ensuring that the milk used in production meets established
standards. Milk samples were analyzed by an Ultrasonic Milk Analyzer, pH
meter, alcohol test, and Resazurin dye reduction test. The results were
analyzed by mean comparison – T-test and process control charts were used
to monitor the variations in milk quality parameters over time. The analytical
results revealed that the mean values for the selected quality parameters
across the sampled regions as follows: pH 6.294±0.28, fat content
4.031±0.24%, SNF content 8.089±0.48%, protein content 3.206±0.19%,
lactose 4.732±0.30%, CLR value 26.35±1.71, added water 0.12±0.02%,
freezing point -0.5555±0.04 °C, solubility index 0.688±0.04 mg/L, and KQ
2.45±0.01. 83%, 14%, and 3% of samples out of selected milk samples were
identified as 77% (-), 72 %(-), and 68 %(-) respectively for the alcohol
precipitation test. This indicates the high microbial activity in grass-root milk
collection. Among the regions studied in this research, raw milk from the
Pothuvil and Gokaralla areas exhibited superior quality, meeting or
exceeding established standards.
