Ricotta whey supplemented with gelatin and collagen for the encapsulation of probiotic lactic acid bacteria

The aim of the present study was to evaluate the viability of probiotic bacteria Lactobacillus acidophilus (LA-5)® and Bifidobacterium lactis (BB-12)® encapsulation using spray drying (SD) with ricotta whey supplemented with gelatin and hydrolyzed collagen as encapsulating material. Following previous experiments, these gelatin:collagen ratios were defined: 7:3 (gelatin:collagen) for L. acidophilus LA-5 and 9:1 for B. lactis BB-12, which had reduced bacterial counts of 0.46 and 1.26 log Colony-Forming Units (CFU)/g, respectively. There was a viability loss of 0.70 log CFU/g and 0.34 log CFU/g for LA-5 and BB-12, respectively, throughout storage (30 days, 25 ºC). When exposed to the simulated gastric juice, encapsulated LA-5 and BB-12 had higher survival rates (89.91 and 95.83%, respectively) than non-encapsulated microorganisms under the same conditions (54.78 and 57.27%, respectively). In the presence of bile salts, encapsulated LA-5 and BB-12 had survival of 77.44% and 51.05%, respectively, while free cells showed rates of over 99%. After 30 days, these rates decreased to 71.07 and 50.60%, for encapsulated LA-5 and BB-12, respectively. Therefore, ricotta whey associated to gelatin and hydrolyzed collagen can be considered a potential encapsulating agent for the SD of probiotic dairy bacteria.