author(s)
Qamar Liaqat, Said Wahab, Irfan Ullah, Naeem Ullah, Usman Ali and Murtaza Ali

abstract
The study was conducted to estimate the effect of antimicrobial agents for example sodium benzoate and potassium sorbate separately and in combination with different concentration for preservation of pear nectar. The samples were packed in 250 ml transparent plastic bottles at room temperature for storage period of 90 days. The treatments were P0 (pear nectar with no preservative), P1 (pear nectar + 0.1% sodium benzoate), P2 (pear nectar + 0.1% potassium sorbate), P3 (pear nectar + 0.05% sodium benzoate), P4 (pear nectar + 0.05% potassium benzoate) and P5 (pear nectar + 0.05% sodium benzoate and 0.05% potassium sorbate). Samples of pear nectar were evaluated for total soluble solids, ascorbic acid, %acidity, pH, reducing and non-reducing sugar and sensory evaluation (color, flavor, taste and overall acceptability). pH decrease from 4.03 to 3.60, total soluble solids increase 14.90 to 16.03, % acidity 0.93 to 1.02,ascorbic acid decrease 7.04 to 5.15, reducing sugar increase 18.03 to 18.28, non-reducing sugar decrease 3.88 to 3.40, color decrease 8.10 to 5.57, flavor 8.20 to 5.75, taste 8.10 to 5.60 and overall acceptability decreased 7.18 to 5.02 during period of storage. The results shows that storage period and treatments had significant effect (p<0.05) on phsico chemical and sensory evaluation of pear nectar. The nectar sample P5 was found best followed by P1, while P0 show the poor results.