Evaluation of malunggay-apple-pineapple juice as a potential functional food matrix for the viability of Lactobacillus plantarum BS25

Abstract

In a separate study, the local probiotic strain Lactobacillus plantarum BS25 was found to have cytotoxic activity against colorectal cancer cells. Moreover, the strain has been reported to confer health benefits upon consumption. This research aimed to develop a functional food matrix that can potentially sustain its probiotic viability. The study evaluated the probiotic viability of BS25 on MAP (malunggay-apple-pineapple juice), MAPm (malunggay-apple-pineapple with milk), and pure milk incubated under room and refrigerated (4?°?C) temperatures. The effects of pH, incubation temperature, and addition of milk was determined. The safety and acceptability of the food matrix was also assessed. Based on a pre-sensory evaluation, the high acceptability scores and preference compared to a commercialized product makes MAP a potential functional food product. However, population counts of BS25 showed that MAP was not able to sustain probiotic viability (>10?6 CFU/mL) after 20 days of incubation. The effect of initial pH to the survival of BS25 is dependent on the ability of the strain to maintain its population at a certain pH (optimum pH = 5.5 to 6.5). Incubation at refrigerated temperature extended BS25 survival because the lower temperature (4°C) slows metabolic activity. For the incorporation of milk, better survivability of BS25 was observed because of the supplementation of growth-promoting compounds. Based on the microbiological standard for fruit juices, the developed food matrix is considered safe only after a week, indicating immediate consumption. Finally, lowered acceptability scores of the inoculated matrix were recorded due to the acidification of drinks, indicating the need for improvements for long term sensory attributes.