Oil-in-water (O/W) emulsions of okara oil-caseinate (1:2; 1:3 and 1:4 O/W ratios) were used to encapsulate Lactobacillus plantarum CIDCA 83114. Once encapsulated, microorganisms were freeze-dried or spray-dried, and observed by scanning electronic and confocal microscopies. A physical characterization of the dehydrated capsules was carried out by determining their moisture content, water activity, particle size, polydispersity index and zeta potential. Determining the induction times and peroxide values provided information about their susceptibility to oxidation. In turn, bacterial stability was analyzed by plate counting before and after freeze-drying and spray-drying, and during storage at 4 °C.

Spray-dried emulsions had lower Z-sizes and polydispersity indexes, higher induction times and lower peroxide values than the freeze-dried ones, thus resulting better systems to protect L. plantarum CIDCA 83114. In addition, the culturability of spray-dried bacteria did not decrease neither after spray-drying nor up to 60 days of storage at 4 °C.

The results showed that the better physical-chemical stability of spray-dried capsules determined the greater stability of microorganisms. This demonstrates the importance of defining adequate emulsions' formulations for an efficient encapsulation of microorganisms, with promising applications in the development of novel functional foods.

豆渣酪蛋白油（1：2； 1：3和1：4 O / W比例）的水包油（O / W）乳液用于封装植物乳杆菌CIDCA83114。一旦封装，微生物就被冷冻干燥。或喷雾干燥，并通过扫描电子显微镜和共聚焦显微镜观察。通过确定其水分含量，水活度，粒径，多分散指数和ζ电位来进行脱水胶囊的物理表征。测定诱导时间和过氧化物值提供了有关它们对氧化的敏感性的信息。依次地，在冷冻干燥和喷雾干燥之前和之后以及在4℃下的储存过程中，通过平板计数来分析细菌的稳定性。

喷雾干燥的乳剂比冷冻干燥的乳剂具有更低的Z值和多分散指数，更长的诱导时间和更低的过氧化物值，因此形成了更好的保护植物乳杆菌CIDCA 83114的系统。喷雾干燥后和在4°C下最多保存60天，都不会降低。

结果表明，喷雾干燥胶囊的更好的物理化学稳定性决定了微生物的更大的稳定性。这证明了为有效地封装微生物定义适当的乳剂配方的重要性，并在开发新型功能性食品方面具有广阔的应用前景。