ABSTRACT

 The study evaluated effect of ginger rhizome addition on physicochemical and sensory properties of pineapple juice. Wholesome pineapple and ginger rhizome were procured from Ndioru market in Umuahia, Abia State. Ginger-pineapple juice were produced from three (3) formulations (90 % pineapple juice: 10 % ginger extract, 80 % pineapple juice: 20 % ginger extract, 70 % pineapple juice: 30 % ginger extract) while 100 % pineapple juice served as the control. The ginger-pineapple juice was analysed for physicochemical properties, vitamin, mineral and sensory properties based on standard methods. The statistical analysis was carried out using one-way ANOVA at 95 % confidence level. Findings showed that the physicochemical properties ranged from 3.62 to 3.92, 14.55 to 16.73 °Brix, 0.78 to 0.97 %, 1.13 to 1.33 g/cm3 and 63.48 to 64.37 for pH, TS, TTA, density and °Brix respectively. The vitamin composition ranged from 0.13 to 0.34 mg/100 g, 0.36 to 2.52 mg/100 g, 0.17 to 0.26 mg/100 g, 60.71 to 158.32 and 1.06 to 2.65 for vitamin Bi, B3, Be, C and E respectively. The mineral composition ranged from 46.20 to 52.41 mg/100 g, 473.71 to 486.76 mg/100 g, 40.83 to 43.81 mg/100 g. 0.34 to 0.75 mg/100 g and 3.42 to 5.13 mg /100 g for magnesium, potassium, phosphorous, iron and manganese respectively. Rhizopus stolinofer and Aspergillus niger were isolated after 3 days of incubation in 100 % pineapple juice and 90 % pineapple juice: 10 % ginger extract respectively , there was moderate growth of Aspergillus niger in 80 % pineapple juice: 20 % ginger extract. No growth was recorded in 70 % pineapple juice: 30 % ginger extract in fungi culture. Staphylococcus aureus was isolated after 24 hours in 100 % pineapple juice and 90 % pineapple juice: 10 % ginger extract respectively, Enterococci was isolated after 24 hours in 80 % pineapple juice: 30 % ginger extract and no growth was observed in 70 % pineapple juice: 30 % ginger extract for bacterial culture, Staphylococcus aureus was isolated in 100 % pineapple juice and 90 % pineapple juice: 10 % ginger extract respectively while Enterococci was isolated in 70 % pineapple juice: 30 % ginger extract for biochemical/ sugar fermentation test. The sensory properties of the ginger-pineapple juice samples ranged from 6.55 to 7.60, 5.45 to 8.00, 6.45 to 7.65, 5.95 to 8.20 and 6.35 to 8.25 for appearance, taste, aroma, mouth feel and general acceptability respectively. Sensory results showed that all the samples were well accepted and consumers indicated there willingness to accept the samples for normal consumption