EVALUATION OF RAW COW MILK PRESERVATION USING EXTRACTEDMANGO SEED KERNELS AND ROSEMARY LEAVESPOWDER, ETHIOPIA

Abstract

The study aimed to evaluate the raw cow milk preservation using extracted mango seed kernels and rosemary (Azmerino) leaves powder, Ethiopia. Mango seed kernels were collected from local juice-making waste, while rosemary leaves were purchased from DebreBerhan market. The crude extracts were isolated from two plant species using Soxhlet extraction method and characterized for the presence of bio-active compounds quantitatively. Fresh raw milk samples collected aseptically from DebreBirhan University dairy farm.The raw cow milk was divided into 10 equal parts: the first part was left without any treatment to serve as a control group, whereas the remaining nine parts were treated at different concentrations (0.5, 1.0 and 1.5%) of ethanol extract of mango seed kerenls extract, rosemary leaves extract and equal mix of the both extracts mixed with 100 ml of milk at room temperature.The DPPH free radical scavenging assay was used to determine the antioxidant capacity of various extracts, and the absorbance was measured at 517 nm. Mango seed kernels powder extract had the highest total phenolic content (TPC) value of 97.4 mg GAE/g, while rosemary leaves powder extract had the lowest at 49.2 mg GAE/g.Similarly, Mango seed kernels and rosemary leaves powder extracts had the total flavonoid content (TFC) value of 36.7 and 34.4 mg CE/g, respectively.The parameters considered for this study was titratable acidity, pH, Total Aerobic Mesophilic Bactria Count, Total Coliform Count and Total Yeast and Mold Count after 0, 24, 48 and 72 hours. The results of the current study showed the values of titratable acidity and pH recorded at 1.5% mango kernel extract up to 48 hours were 0.17 and 6.52, respectively. The lowest total aerobic mesophilic bacterial and total coliform counts of 7.96 and 4.30logcfu/ml respectively were observed at 1.5% mango kernel extract up to 48 hours. However, both bacterial counts were observed in the current study was beyond the acceptable consumption limit of Ethiopia standard agency (5.30 to 6.00 log cfu/ml), so the milk reaches to the collection centerbeteewn 24 and 48 hours. The result showed that are titratable acidity, pH, Total Aerobic Mesophilic Bactria Count and Coliform Count) significant differences (P<0.05). In conclusion, ethanol extract kernels were higher antimicrobial activity than rosemary leaves extract as result ethanol extracts performed well in milk preservation. Generally, Mango seed kernels powder extracts had the longest shelf life that compared from rosemary and mixed plant extracts tested for milk samples.Further study by increasing proportion up to 2% of mango seed kernels extracts effect on physical and microbial effect of milk is essential.