ANTIOXIDANT AND SENSORY EVALUATION OF LIME PRESERVED FRUIT JUICE

ABSTRACT

The major challenge influencing economic value of fruit juice is the relative short shelf life and chemical preservatives content such as potassium sorbate and sodium benzoate, which are used industrially. These preservatives have long term negative health impact after consumption. Hence the need to search for an alternative and sustainable mode of preservation. The aim of this research was to access the preservative efficacy of lime on fruit juice by determining the phytochemical vitamin C, lycopene and sensory properties of the juice. Pineapple, lime and watermelon fruits were purchased from an open market in Benin City and processed into juice. Then treated by pasteurizing, with freeze dried lime extract of different concentrations. Then the untreated samples were used as control. pH, titrable acidity (TA) and vitamin C content of the treated and untreated fruit juice samples were assessed using methods described by AO AC at 24hrs interval for 72hrs. Also lycopene content, and sensory evaluation was assessed using standard methods. The pH and titratable acidity (TA) did not increase significantly from day 0- 48hrs for lime preserved juice. The pH and TA ranged from 3.47±0.001 to 2.47 ± 0.01 and 2.14±0.00 to 1.10±0.00 respectively. The vitamin C content and beta-lycopene content ranged from 0.60±0.00 to 0.13±0.00 and 4.67±0.04 to 1.65±0.03 respectively. Also the sensory assessment scored 8.50±0.40 based on appearance and 6.55±0.61 based on smell and 7.00±0.55 based on overall impression. The findings have revealed that the freeze dried lime extract was able to improve the shelf life of fruit juice for 48hrs.