Improving the survival of Lactobacillus plantarum NRRL B-1927 during microencapsulation with ultra-high-pressure-homogenized soymilk as a wall material

George Cavender; Nan Jiang; Rakesh K Singh; Jinru Chen; Kevin Mis Solval

doi:10.1016/j.foodres.2020.109831

Improving the survival of Lactobacillus plantarum NRRL B-1927 during microencapsulation with ultra-high-pressure-homogenized soymilk as a wall material

Food Res Int. 2021 Jan:139:109831. doi: 10.1016/j.foodres.2020.109831. Epub 2020 Oct 26.

Authors

George Cavender¹, Nan Jiang², Rakesh K Singh³, Jinru Chen², Kevin Mis Solval⁴

Affiliations

¹ Department of Food Science and Technology, The University of Georgia, Athens, GA 30602, USA; Currently at Cooperative Research and Extension Division, Lincoln University, Jefferson City, MO 65101, USA.
² Department of Food Science and Technology, The University of Georgia, Griffin, GA 30223, USA.
³ Department of Food Science and Technology, The University of Georgia, Athens, GA 30602, USA.
⁴ Department of Food Science and Technology, The University of Georgia, Griffin, GA 30223, USA. Electronic address: kmissolval@uga.edu.

PMID: 33509456
DOI: 10.1016/j.foodres.2020.109831

Abstract

Probiotic foods and supplements have been shown to offer multiple potential health benefits to consumers. Dried probiotic cultures are increasingly used by the food industry because they are easily handled, transported, stored, and used in different applications. However, drying technologies often expose probiotic cells to extreme environmental conditions that reduces cell viability. Hence, this study aimed to evaluate the effect of using ultra high-pressure homogenization (UHPH) on soymilk's microencapsulating ability, and the resultant effect on the survivability of probiotic Lactobacillus plantarum NRRL B-1927 (LP) during drying. Liquid suspensions containing LP (~10⁹ CFU/g of solids) were prepared by suspending LP cultures in soymilk which had been either treated with UHPH at 150 MPa or 300 MPa or left untreated. LP suspensions were then dried by concurrent spray drying (CCSD), mixed-flow spray drying (MXSD) or freeze-drying (FD). Cell counts of LP were determined before and after microencapsulation. Moisture, water activity, particle size and morphology of LP powders were also characterized. LP powders produced with 300 MPa treated soymilk had 8.7, 6.4, and 2 times more cell counts than those produced with non-UHPH treated soymilk during CCSD, MXSD, and FD, respectively. In the 300 MPa treated samples, cell survival (%) of LP during drying was the highest in MXSD (83.72) followed by FD (76.31) and CCSD (34.01). Using soymilk treated at higher UHPH pressures resulted in LP powders with lower moisture content, smaller particle sizes and higher agglomeration. LP powders produced via MXSD showed higher agglomeration and fewer signs of thermal damage than powders produced via CCSD. This study demonstrates that UHPH improves the effectiveness of soymilk as a microencapsulant for probiotics, creating probiotic powders that could be used in plant-based and non-dairy foods.

Keywords: Particle size; Probiotics; Soymilk; Spray drying; Ultra-high-pressure homogenization.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Desiccation
Freeze Drying
Lactobacillus plantarum*
Probiotics*
Soy Milk*