Storage stability of food-grade recombinant Lactococcus lactis NZ3900-fermented milk expressing K-ras mimotopes

• Published in: Journal of food measurement & characterization 2024-03, Vol.18 (3), p.2184-2195
• Main Authors: How, Yu Hsuan, Teo, Michelle Yee Mun, In, Lionel Lian Aun, Yeo, Siok Koon, Bhandari, Bhesh, Pui, Liew Phing
• Format: Article
• Language: English
• Subjects: Acidification; Acidity; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Colorectal carcinoma; Engineering; Fermentation; Fermented food; Fermented milk products; Food Science; Lactococcus lactis; Milk; Original Paper; Physicochemical properties; Shelf life; Skim milk; Stability analysis; Storage stability; Sucrose; Survivability; Syneresis; Vaccines
• ISSN: 2193-4126; 2193-4134
• DOI: 10.1007/s11694-023-02316-6

K-ras mimotope expressed by Lactococcus lactis NZ3900 is a potential live oral vaccine developed to target specific K-ras mutations in colorectal cancer. However, the storage and delivery of live oral vaccines through the harsh gastrointestinal environment remains a challenge. Hence, this study was aimed to evaluate the storage stability of Lactococcus lactis NZ3900 expressing K-ras mimotopes in fermented milk. The L. lactis NZ3900 expressing K-ras mimotopes was incorporated into skim milk for fermentation. The L. lactis -fermented milk was added with sucrose and stored for 42 days at 4 °C. The L. lactis NZ3900-fermented milk without sucrose was served as control. On day 28 of storage, L. lactis NZ3900-fermented milk with sucrose displayed high viability (8.05 log 10 CFU/mL), acceptable post-acidification activity (0.91% titratable acidity, pH 4.11), comparable physicochemical properties (13,949 mPa s viscosity, 71.4% syneresis, 5.83°Brix, Δ E = 1.68) with K-ras mimotope expression, and high survivability after simulated sequential digestion (82.5%). This suggests that fermented milk with sucrose is a suitable delivery carrier for this live oral vaccine.