Phenolic compound profile of probiotic (Lacticaseibacillus rhamnosus LR5) fortified vegetable tablet and probiotic survival in the simulated gastrointestinal tract.

The objectives of this research were to study the changes of phenolic compounds in vegetable (yellow VS green) tablets with/without probiotics (Lacticaseibacillus rhamnosus LR5) supplementation by using high performance liquid chromatography and probiotic survivability through the simulated gastrointestinal tract. The green vegetable tablets with/without probiotics had a greater (p ≤ 0.05) phenolic content compared to the yellow ones. There were no significant differences of most phenolic compound contents between probiotic-supplemented vegetable tablets and non-probiotic supplemented ones (p > 0.05). The contents of ferulic acid, epicatechin, tannic acid and rutin for both vegetable tablets tended to decrease through passing the stomach (1 and 2 h) and small intestine (2 and 4 h), however, the content of catechin in the yellow vegetable tablets tended to increase. The results also showed that the survival of Lacticaseibacillus rhamnosus LR5 slightly decreased through the simulated gastrointestinal tract. The vibrations from FTIR appeared in the wave length of 4000-3100, 3000-2800 and 1652-1545 cm-1, which accounted for the change in the N-H bonds of the amine group, changes in the structure of fatty acids and the change of carbonyl groups, respectively. This work highlighted the opportunity of application of probiotics in food products; especially non-dairy foods for consumer with dairy allergy.

Spray-drying microencapsulation using whey protein isolate and nano-crystalline starch for enhancing the survivability and stability of Lactobacillus reuteri TF-7.

Decrease of survivability and stability is a major problem affecting probiotic functional food. Thus, in this study, Lactobacillus reuteri TF-7 producing bile salt hydrolase was microencapsulated in whey protein isolate (WPI) or whey protein isolate combined with nano-crystalline starch (WPI-NCS) using the spray-drying technique to enhance the survivability and stability of probiotics under various adverse conditions. Spherical microcapsules were generated with this microencapsulation technique. In addition, the survival of L. reuteri TF-7 loaded in WPI-NCS microcapsules was significantly higher than WPI microcapsules and free cells after exposure to heat, pH, and simulated gastrointestinal conditions. During long-term storage at 4, 25, and 35 °C, WPI-NCS microcapsules could retain both survival and biological activity. These findings suggest that microcapsules fabricated from WPI-NCS provide the most robust efficiency for enhancing the survivability and stability of probiotics, in which their great potentials appropriate to develop as the cholesterol-lowering probiotic supplements.