Abstract
Radiant energy under vacuum (REV) as a rapid dehydration method was employed to dehydrate Lactobacillus salivarius 417 along with different concentrations of skim milk powder as protective medium. Two optimization methods: response surface methodology and random centroid analysis (RCO) were applied and compared to optimize the dehydration parameters for maximum viability—microwave power, absolute pressure in the drying chamber, and protective agent concentration. The study showed that both methods were suitable for the process optimization. Microwave power, concentration of skim milk powder, and absolute pressure had a significant effect on final viability while the speed of sample rotation in vertical axis had no effect (P < 0.05). The result also indicated that a microwave power of <250 W, 10–15% concentration of skim milk powder, and <1 mmHg absolute pressure was needed to achieve viability of equal or greater than 80% in L. salivarius. The RCO-optimized REV process yielded higher viability than the reference freeze drying method and was completed in less than an hour as compared to 64 h for freeze drying.
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Abadias, M., Benabarre, A., Teixido, N., Usall, J., & Vi, I. (2001). Effect of freeze drying and protectants on viability of the biocontrol yeast Candida sake. International Journal of Food Microbiology, 65, 173–182.
Adinarayana, K., Ellaiah, P., Srinivasulu, B., Bhavani, R., & Adinarayana, G. (2003). Response surface methodological approach to optimize the nutritional parameters for nomycin production by Streptomyces marinensis under solid-state fermentation. Process Biochemistry, 38, 1565–1572.
Ahmad, S., Yaghmaee, P., Durance, T. D. (2007). Survival of probiotic bacteria and food yeast dehydrated with microwave energy under vacuum. 41st Annual Microwave Symposium Proceedings, 30–34.
Association of Official Analytical Chemists. (2002). Official methods of analysis of AOAC International (17th edition). Gaithersburg: AOAC International.
Berny, J. F., & Hennebert, G. L. (1991). Viability and stability of yeast cells and filamentous fungus spores during freeze-drying: effects of protectants and cooling rates. Mycologia, 83, 805–815.
Carvalho, A. S., Silva, J., Ho, P., Teixerira, P., Malcata, F. X., & Gibbs, P. (2004). Effects of various sugars added to growth and drying media upon thermotolerance and survival throughout storage of freeze-dried Lactobacillus delbrueckii ssp. bulgaricus. Biotechnology Progress, 20, 248–254.
Champagne, C. P., Garnder, N., Brochu, E., & Beaulieu, Y. (1991). The freeze drying of lactic acid bacteria. Canadian Institute of Food Science and Technology Journal, 24, 118–128.
Cheynier, V., Feinberg, M., Chararas, C., & Ducauze, C. (1983). Application of response surface methodology to evaluation of bioconversion experimental conditions. Applied and Environmental Microbiology, 45, 634–639.
Conrad, P. B., Miller, D. P., Cielenski, P. R., & De Pablo, J. J. (2000). Stabilization and preservation of Lactobacillus acidophilus in saccharide matrices. Cryobiology, 41, 17–24.
De Giulio, B., Orlando, P., Barba, G., Coppola, R., De Rosa, M., Sada, A., et al. (2005). Use of alginate and cryo-protective sugars to improve the viability of lactic acid bacteria after freezing and freeze-drying. World Journal of Microbiology & Biotechnology, 21, 739–746.
Durance, T. D., Yaghmaee, P., Ahmad, S., Zhang, G. (2007). Method for dehydrating biological material. PCT/CA2007/000134.2007.
Kim, S. S., Shin, S. S., Chang, K. S., Kim, S. Y., Noh, B. S., & Bhomik, S. R. (1997). Survival of lactic acid bacteria during microwave vacuum drying of plain yoghurt. Lebensmittel-Wissenschaft und Technologie, 30, 573–577.
Koh, S. P., Tan, C. P., Lai, O. M., Arifin, N., Yusoff, M. S. A., & Long, K. (2010). Enzymatic synthesis of medium- and long-chain triacylglycerols (MLCT): optimization of process parameters using response surface methodology. Food and Bioprocess Technology, 3, 288–299.
Leslie, S. B., Israeli, E., Llighthart, B., Crowe, J. H., & Crowe, L. M. (1995). Trehalose and sucrose protect both membranes and proteins in intact bacteria during drying. Applied and Environmental Microbiology, 61, 3592–3597.
Linders, L. J. M., de Jong, G. I. W., Meerdink, G., & van’t Riet, K. (1997). Carbohydrates and the dehydration inactivation of Lactobacillus plantarum: the role of moisture distribution and water activity. Journal of Food Engineering, 31, 237–250.
Ming, L. C., Rahim, R. A., Wan, H. Y., & Ariff, A. B. (2009). Formulation of protective agents for improvement of Lactobacillus salivarius I 24 survival rate subjected to freeze drying for production of live cells in powderized form. Food and Bioprocess Technology, 2(4), 431–436.
Montgomery, D. C. (1991). Design and analysis of experiments (3rd ed.). New York: John Wiley & Sons.
Morgan, C. A., Herman, N., White, P. A., & Vessey, G. (2006). Preservation of microorganisms by drying; a review. Journal of Microbiological Methods, 66, 183–193.
Nakai, S. (1981). Comparison of optimization techniques for application to food product and process development. Journal of Food Science, 47(144–152), 157.
Nakai, S. (1990). Computer-aided optimization with potential application in biorheology. Journal of Japanese Biorheology Society, 4, 143–152.
Nakai, S., Dou, J., Lo, V., & Scaman, C. H. (1998). Optimization of site-directed mutagenesis. 1. New random-centroid optimization program for Windows useful in research and development. Journal of Agricultural and Food Chemistry, 46, 1642–1654.
Neter, J., Kutner, M. H., Nachtsheim, C. J., & Wasserman, W. (1996). Applied linear statistical models. Chicago: McGraw-Hill.
Random Centroid Optimization (RCO). (2007) Instructions of the RCO program. In: S. Nakai (Ed.). Canada: Faculty of Food and Land systems, University of British Columbia.
Scaman, C. H., & Durance, T. D. (2005). Combined microwave vacuum drying. In Emerging technologies for food processing (1st ed.). London: Elsevier.
Thammavongs, B., Corroler, D., Panoff, J. M., Auffray, Y., & Boutibonnes, P. (1996). Physiological response of Enterococcus faecalis JH2-2 to cold shock: growth at low temperatures and freezing/thawing challenge. Letters in Applied Microbiology, 23, 398–402.
To, B. C. S., & Etzel, M. (1997). Survival of Brevibacterium linens (ATCC 9174) after spray drying, freeze drying, or freezing. Journal of Food Science, 62, 167–170.
Uzunova-Doneva, T., & Donev, T. (2000). Influence of the freezing rate on the survival of strains Saccharomyces cerevisiae after cryogenic preservation. Journal of Culture Collection, 3, 78–83.
Visick, J. E., & Clark, S. (1995). Repair, refold, recycle: how bacteria can deal with spontaneous and environmental damage to proteins. Molecular Microbiology, 16, 835–845.
Yaghmaee, P., & Durance, T. D. (2005). Destruction and injury of Escherichia coli during microwave heating under vacuum. Journal of Applied Microbiology, 98, 498–506.
Zayed, G., & Roos, Y. H. (2004). Influence of trehalose and moisture content on survival of Lactobacillus salivarius subjected to freeze-drying and storage. Process Biochemistry, 39, 1081–1086.
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The authors thank the Natural Sciences and Engineering Research Council of Canada (NSERC) student fellowship and are grateful for the NSERC research grant.
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Ahmad, S., Yaghmaee, P. & Durance, T. Optimization of Dehydration of Lactobacillus salivarius Using Radiant Energy Vacuum. Food Bioprocess Technol 5, 1019–1027 (2012). https://doi.org/10.1007/s11947-010-0437-y
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DOI: https://doi.org/10.1007/s11947-010-0437-y