Product development of gac fruit juice incorporated with lime juice

Gac fruit is widely cultivated in Thailand. It has elevated amounts of phytochemical compounds such as lycopene and β-carotene, with the aril section being the richest in these compounds. Lime juice is a healthy drink that is generally consumed for its nutritive value. The purpose of this study was to carry out an assessment to identify the appropriate proportion of lime for blended lime and gac fruit juice processing. This research consisted of four experiments. Fresh gac fruit juice (as a control sample; 0% and blended gac fruit juice with 5%, 10% and 15% concentrations of lime juice were analysed. Physical properties were examined, including brightness and colour (L*, a* and b* values), as well as chemical properties such as total acidity percentage, pH, vitamin C, total soluble solids, β-carotene, antioxidant inhibition percentage (DPPH assay) and lycopene. For the assessment of microbiological properties, a total plate count was carried out. A sensory evaluation for colour, odour, flavour, mouthfeel as well as overall acceptability was performed by thirty untrained panelists using the 9-point hedonic scale. Concerning the physical properties, it was determined that an increase in the amount of lime juice caused an escalation in external colour, odour and sediments. Analysis of the chemical properties revealed that all treatments were significantly different (p<0.05), except for β-carotene and total soluble solids. The chemical properties showed that lycopene, antioxidant inhibition percentage (as DPPH assay) and β-carotene were within the ranges of 647.32- 650.48 µg/g, 4.23-4.65% and 441.95-444.16 µg/g, respectively; they were not significantly different except for the antioxidant inhibition percentage and β-carotene. An increase in the amount of lime juice caused an increase in the external appearance of vitamin C sediments and total acidity percentage. The findings of the microbiological analysis demonstrated that the total plate count met the standard regulations, while the sensory evaluation revealed that the flavour, mouthfeel and overall acceptability for experiment no. 3 (10% of lime juice) obtained the highest values of 7.37, 6.90 and 7.33, respectively.