Physicochemical analysis, microbial survivability, and shelf life study of spray‐dried synbiotic guava juice powder

Abstract

In this work the survival of Lactobacillus plantarum in guava juice upon spray-drying process using maltodextrin (MD) and inulin (INU) as drying carriers was evaluated. The microbial viability, color, water activity (Aw), and rehydration time in spray-dried lacto-fermented guava juice powder were evaluated at room temperature (25°C) and refrigerated conditions (4°C) for 45 days. Spray drying was done at inlet temperature of drying air 120°C, feed flow rate 5 ml/min, hot air flow 3.0 m3/min, pressurized air flow 30 L/min, and outlet temperature at 75°C. Results indicated that the highest survival rates of 80% for 45 days and 85% up to 15 days were observed at 4°C and 25°C, respectively, for powders obtained using 10% MD + 10% INU blend. Highest yield and lowest rehydration time were obtained by 20% MD. Aw was maintained low and no color difference in the product was seen in any of the formulations. Practical Applications The practical applications of this research will help in catering the growing demand for functional foods with nondairy food matrix containing both prebiotics and probiotics (known as synbiotic). In the present work a source of prebiotic-guava and lactobacillus strain as a probiotic was used to formulate a, synbiotic beverage which was then spray dried in optimized method. Such unique combinations improve the nutritional attributes and bring forth health benefits of fruit juices, and delivers health potential from both sources (fruit juices and probiotics). This spray-dried synbiotic powder will be a preferred choice for lactose-intolerant people. The synbiotic not only help in immunomodulatory functions but also help in efficient functioning of gut microbiota which is scientifically related to many body vitals. The most critical practical challenge of preserving the needed microbial viability over shelf life is also dealt with in the present work. This consumer friendly form not only offers an ease of commercial transport but a closely packed form of deliverables for combating micronutrient deficiency.