EP-4736845-A1 - SPRAY DRIED SYNBIOTIC MICROCAPSULES OF ENHANCED STORAGE STABILITY AND PROBIOTIC ACTIVITY

Abstract

The present invention concerns novel synbiotic microcapsules of enhanced storage stability at room temperature. The symbiotic microcapsules are produced in a single step by spray drying, and present a microcapsule composition consisting essentially of a probiotic, and a mixture of a prebiotic preferably inulin, maltodextrin, and a protective colloid selected from the group consisting of gum Arabic, starch, rice starch, modified starches, pectin, xanthan gum and mixtures thereof. The invention also proposes a spray drying process easy to operate and providing excellent encapsulation and efficiency yields. The synbiotic microcapsules have proven to effectively protect the encapsulated probiotic during gastrointestinal transit and to provide a probiotic effect on in vitro and in vivo essays.

Inventors

• GARFIAS-NOGUEZ, Cynthia
• RAMÍREZ-DAMIÁN, Morayma
• SÁNCHEZ-PARDO, María Elena
• BERMÚDEZ-HUMARÁN, Luis
• ALAMILLA-BELTRÁN, Liliana

Assignees

• Institut National de la Recherche pour l'Agriculture, l'Alimentation et l'Environnement
• Institut National des Sciences et Industries du Vivant et de L'Environnement
• Université Paris-Saclay
• Instituto Politecnico Nacional

Dates

Publication Date

20260506

Application Date

20241105

Claims (15)

1. Synbiotic microcapsules, wherein such microcapsules are obtained by spray-drying and comprise a composition consisting essentially of a probiotic and a mixture of: - a prebiotic selected from the group consisting of fructooligosaccharides (FOS), galactooligosaccharides (GOS), xylooligosaccharides (XOS), and arabinoxylans and mixtures thereof; - maltodextrin, and - a protective colloid selected from the group consisting of gum Arabic, starch, modified starches, pectin, xanthan gum and mixtures thereof.
2. Synbiotic microcapsules according to claim 1, wherein the prebiotic is inulin.
3. Synbiotic microcapsules according to one of the preceding claims, presenting a moisture content of 4% to 6%w/w, and a water activity ≤ 0.4, preferably ≤0.35.
4. Synbiotic microcapsules according to one of the preceding claims, wherein the prebiotic is inulin and the protective colloid is gum Arabic or is mainly composed of gum Arabic.
5. Synbiotic microcapsules according to one of the preceding claims, wherein the microcapsules present enhanced storage stability at room temperature such that an initial viability counting of such symbiotic microcapsules decreases less than 4 log CFU/g after 12 months storage at 25°C, at preferably no more than 3 log CFU/g.
6. Synbiotic microcapsules according to one of the preceding claims, wherein the composition presents the following content in w/v % when present in aqueous solution: 1 - 10% of prebiotic, more preferably 2-8%, more preferably 3-7 %; 5 - 15% of maltodextrin, preferably 5-10% 5 - 15% of protective colloid, preferably 5-10%; and wherein the total solid content in such aqueous solution, excluding the probiotic, is 20 - 30 %w/v, preferably 20-25% w/v.
7. Synbiotic microcapsules according to one of the preceding claims, wherein the composition presents the following content in w/v % when present in aqueous solution: 3 - 7 % of inulin as prebiotic, preferably 4-6%; 5 - 15% of maltodextrin, preferably 5-10%; 5 - 10% of gum Arabic as protective colloid, and wherein the total solid content in such aqueous solution, excluding the probiotic, is 20-25% w/v.
8. Synbiotic microcapsules according to one of the preceding claims, wherein such probiotic is a lactic acid bacteria, a bifidobacteria or a mixture thereof, and wherein such probiotic is preferably Lacticaseibacillus rhamnosus, Levilactobacillusbrevis , Lactiplantibacillus plantarum or a mixture thereof.
9. Synbiotic microcapsules according to one of claims 1 to 8 for use in the treatment and/or prevention of chronic inflammatory bowel diseases, such as ulcerative colitis.
10. Synbiotic microcapsules according to one of claims 1 to 8 for use in the treatment and/or prevention of gastrointestinal diseases and disorders including colorectal cancer, and/or for their use as probiotics, antioxidants, antimicrobials and/or antiinflammatories.
11. Synbiotic microcapsules for use according to one of claims 9 to 10, comprising Lactiplantibacillus plantarum as probiotic.
12. Food product, nutraceutical or medicament with a composition including synbiotic microcapsules according to one of claims 1 to 8.
13. Process for obtaining synbiotic microcapsules according to one of claims 1 to 8, comprising the following actions: a) Preparing an aqueous dispersion including all the microcapsule composition components, and b) Air spray-drying such aqueous suspension.
14. Process according to claim 13, wherein in b) air spray- drying is performed with an inlet temperature of 130°C to 170°C, preferably 145°C-165°C, and an outlet temperature of 65°C to 85°C, preferably 70°C-80°C.
15. Process according to one of claims 13 or 14, wherein in b) air spray- drying is performed using a dosing speed of 8 to 27 mL/min, and/or an atomizing pressure of 1 to 2 bar, and/or using natural air as heating fluid.

Description

TECHNICAL FIELD The present invention concerns new spray dried synbiotic microcapsules and a process for microencapsulation thereof. In particular, the invention proposes new microcapsules comprising a mixture of probiotics and prebiotics (i.e. synbiotic) exhibiting enhanced storage stability without the need for refrigeration. The invention also proposes a spray drying process providing excellent encapsulation and efficiency yields. The synbiotic microcapsules have proven to effectively protect the encapsulated probiotic during gastrointestinal transit and to provide a probiotic effect on in-vitro and in-vivo essays. STATE OF THE ART Probiotics are live microorganisms that, when administered in adequate amounts, offer health benefits to the host (FAO/WHO, 2002). Among these, lactic acid bacteria (LAB) such as lactobacilli, streptococci, and enterococci, along with bifidobacteria, are the most extensively studied genera of probiotics. These microbes not only enhance sensory qualities and produce organic acids and bacteriocins during food fermentation, but also significantly benefit intestinal functions. They contribute to balancing intestinal microbiota, regulating intestinal transit, maintaining acid-base balance in the colon, and modulating immune responses. Additionally, they exhibit antimicrobial, antioxidant, and anti-inflammatory effects. For example, probiotics are being studied as alternative treatment to chronic inflammatory bowel disease (IB) like ulcerative colitis, which presents a complex multifactorial etiopathogenesis and wherein progression is primarily characterized by dysregulated immune responses and dysfunctions in the intestinal barrier which some probiotic can help to restore. The beneficial impacts of probiotics often stem from their ability to survive in the gastrointestinal tract, adhere to epithelial surfaces, and modulate immune systems. To ensure the efficacy of probiotics, strategies aiming to enhance the viability of these bacteria are being explored. Among them, encapsulation has emerged as one of the main techniques. This process involves encasing the probiotic microorganism in a protective coating matrix that remains stable and resistant until it releases its content in specific environments. This encapsulating strategy enhances protection of probiotics during manufacturing, storage, and passage through the gastrointestinal tract. The international patent application WO 2019/144979 discloses a method of coating and encapsulation for probiotics which allows for extended and stable storage of such products without the need for refrigeration. A two-step method is proposed wherein a probiotic core is first carried out using a fluid bed and a binder solution (gum Arabic) with stabilizing materials (trehalose, vitamin E acetate, and whole milk powder). In a second step, the obtained granules are coated by spraying a film-forming solution consisting of polyvinyl alcohol in water. With a total process time of around 300 minutes, this process and formulation allows obtaining probiotic microcapsules with a viability of up to 109 CFU/g after 12 months. However, the processing time is long and the formulation requires several ingredients, including stabilizers and a coating polymer. Spray drying is an alternative method for microencapsulating probiotics in a single step. Spray drying involves atomizing a probiotic suspension or solution-comprising both bacteria and the encapsulating material-into fine droplets within a hot air stream. This causes rapid solvent evaporation, resulting in the formation of microencapsulated solid particles. However, during spray-drying process, the membrane of probiotic cells gets damaged, and as a result, they are vulnerable to heat and dehydration. Careful set-up of the process parameters and proper formulation is therefore needed to protect the probiotics during air drying. The international patent application WO 2015/063090 gives an example of a spray drying microencapsulation method for lactic acid bacteria using GEA Niro Mobile Minor spray drying. An inlet temperature of 66°C and an outlet temperature of 39°C were used, with nitrogen as the heating fluid. Maltodextrin 12 DE, inulin, trehalose dihydrate, and sodium ascorbate were utilized, with a total solid's percentage of 51%. In particular, it is suggested to keep the sprayed particles for maximum 20 minutes in the spray dryer, and to convey the sprayed dried material to a secondary cyclone separator by means of a cooling gas. They achieved a bacterial concentration of 2.0E+1 1 CFU/g ±15% with drying yields of 90%, moisture content of 7.5% and water activity of about 0.24. After three weeks, viability decreased to 8E+10 CFU/g. Although the formulation and process allow a high encapsulation efficiency, the microcapsules lose an order of magnitude in just three weeks. Moreover, the method uses nitrogen as heating fluid (elevating production costs) and the formulation requires stabilizers. Arepally et