Pages: (35-42 )
Abstract
Microbial community structure, compositional and physicochemical changes were investigated in samples of lime juice stored in plastic bottles at 27°C±2.0 oC on wooden and cemented surfaces at intervals of 72 hours over a period of one month. Control samples were stored on cemented surfaces but wrapped in aluminum foil to prevent direct penetrative effect of radiation from radon gas contained in cement. At the end of the study, Candida albicans was isolated from all the samples at population density of 1.2 x 104, 10.0 x 104 and 8.0 x 104 cfu/ml in the cement, wooden and aluminum foil -wrapped samples respectively. Samples on cement surface showed a reduction from 9180-6140 NTU, 1.88-1.28 and 2.26-2.24 while results for samples on wooden surface ranged from 5790-6740 NTU, 1.88 - 1.52 and 2.26 - 2.29 for turbidity, optical density (OD) and pH respectively. Results for the control samples ranged from 9870-5880 NTU, 1.88-1.38 and 2.26 - 2.28 for turbidity, OD and pH. Gas chromatographymass spectrometry (GC-MS) analysis indicated the aluminum foil-wrapped samples retained 91-99% of their fatty acid components and had less degradation of nutrients compared to the experimental samples. Results showed that lime essential oils which are used as flavoring agents in beverages, foods and pharmaceuticals are better preserved when lime juices are
stored in the dark and non-cemented surfaces away from effect of radioactive radon gas emitted from cemented surfaces.
Keywords: Radioactive elements, Radon gas, Lime juice, Cemented surface, wooden surface.,