Abstract

Spray-dried whole pineapple juice powder containing a live probiotic was developed for reconstitution into a probioticated drink. The juice extracted from the pineapple pulp and peel was first fermented with the probiotic bacterium Lactobacillus plantarum WU-P19 and then spray-dried. The response surface method was used to optimize the spray-drying variables (the inlet air temperature and the concentration of maltodextrin additive in the juice) to produce a dry powder with acceptable physicochemical properties and probiotic survival for reconstitution into a drink. The optimally dried powder (product PWP-9; dryer inlet air temperature = 150 °C, maltodextrin additive content = 20 % w v^-1) had a viable probiotic count of 10^9.1 colony forming units (CFU) g⁻¹ and excellent sensory appeal. After in vitro simulated gastrointestinal digestion, the viability of the probiotic was 10^7.7 CFU g⁻¹. A 200 mL reconstituted drink based on PWP-9 fully met the daily nutritional requirements of vitamin B12 for an adult. After a 90-day refrigerated storage (4 °C) of PWP-9, the probiotic viability was stable at 10^8.12 CFU g⁻¹, but declined to 10^6.03 CFU g⁻¹ if storage was at 25 °C. The product PWP-9 was shelf-stable and could be reconstituted into a probioticated drink rich in vitamin B12.