RESULTS: Pineapple juice vinegar, which had the highest total phenolic acid content, also exhibited the greatest in vitro antioxidant capacity compared to coconut juice and nipah juice vinegars. Following acute and sub-chronic in vivo toxicity evaluation, no toxicity and mortality were evident and there were no significant differences in the serum biochemical profiles between mice administered the vinegars versus the control group. In the sub-chronic toxicity evaluation, the highest liver antioxidant levels were found in mice fed with pineapple juice vinegar, followed by coconut juice and nipah juice vinegars. However, compared to the pineapple juice and nipah juice vinegars, the mice fed with coconut juice vinegar, exhibited a higher population of CD4+ and CD8+ T-lymphocytes in the spleen, which was associated with greater levels of serum interleukin-2 and interferon-γ cytokines.
CONCLUSIONS: Overall, the data suggested that not all vinegar samples cause acute and sub-chronic toxicity in vivo. Moreover, the in vivo immunity and organ antioxidant levels were enhanced, to varying extents, by the phenolic acids present in the vinegars. The results obtained in this study provide appropriate guidelines for further in vivo bioactivity studies and pre-clinical assessments of vinegar consumption. © 2017 Society of Chemical Industry.
METHODS: A full factorial design (23) was applied to study the effects of mango-pineapple ratio (x1), immersion time in sugar solution (x2), and concentration of sugar solution (x3) in the production of mango-pineapple jelly spheres using frozen reverse spherification. The responses studied were the physicochemical properties (color, total soluble solids, and texture) and sensory evaluation of mango-pineapple jelly spheres.
RESULTS: Mango-pineapple ratio had a positive effect on a* and b* while having a negative effect L* value on the jelly sphere. Total soluble solids of jelly spheres were influenced by both immersion time in sugar solution and concentration of sugar solution. Immersion time in sugar solution had a positive effect on the peak force of the compression cycle and deformation at peak load while having a negative effect on the total soluble solid of jelly spheres. On the other hand, the concentration of sugar solution had a positive effect on the sensory evaluation in terms of flavor, texture, and overall acceptability. The desirability function approach was used to optimize the factors, and an overall desirability of 0.89 for all responses was achieved with 1.28:1 mango-pineapple ratio, 30 mins immersion time in sugar solution, and 22°Brix sugar solution. A proximate analysis of the optimized mango-pineapple jelly spheres had an energy content of 73.18 kcal/100 g and showed nutrient values of 81.11% moisture, 0.10% ash, 0.46% protein, 0% fat, 0.97% total dietary fiber, and 17.35% digestible carbohydrate.
CONCLUSIONS: The development of the optimal mango-pineapple jelly sphere allows food producers to produce a dessert that is low in calories, with a good appearance and consumer acceptability.
RESULTS: The key volatile compounds and aroma profile of six pineapple varieties grown in Malaysia were investigated by gas chromatography-olfactometry (GC-O), gas-chromatography-mass spectrometry and qualitative descriptive sensory analysis. A total of 59 compounds were determined by GC-O and aroma extract dilution analysis. Among these compounds, methyl-2-methylbutanoate, methyl hexanoate, methyl-3-(methylthiol)-propanoate, methyl octanoate, 2,5-dimethyl-4-methoxy-3(2H)-furanone, δ-octalactone, 2-methoxy-4-vinyl phenol, and δ-undecalactone contributed greatly to the aroma quality of the pineapple varieties, due to their high flavour dilution factor. The aroma of the pineapples was described by seven sensory terms as sweet, floral, fruity, fresh, green, woody and apple-like.
CONCLUSION: Inter-relationship between the aroma-active compounds and the pineapples revealed that 'Moris' and 'MD2' covaried majorly with the fruity esters, and the other varieties correlated with lesser numbers of the fruity esters. Hierarchical cluster analysis (HCA) was used to establish similarities among the pineapples and the results revealed three main groups of pineapples.