This paper is only available as a PDF. To read, Please Download here.
Abstract
The response to bacteriophage contamination of a free cell and an immobilized cell bioreactor was studied during continuous pH-controlled fermentation of milk with Lactococcus lactis ssp. lactis. After phage infection (1 × 105 pfu/ml), the phage population reached 1010 pfu/ml in a free cell bioreactor operated at a dilution rate of 0 .5/h and then declined to about 107 pfu/ml as a phage-resistant cell population became established in the system. In the immobilized cell bioreactor operated at dilution rates of 0.5 and 3/h, the phage population continuously increased until reaching 1010 pfu/ml where it remained throughout the 48 h of continuous culture. Conversely, phage populations decreased during the first 30 min following contamination at dilution rates of 10 and 15/h but subsequently increased. For all tested conditions in the immobilized cell bioreactor, the phage-resistant population increased to 102 to 104 cfu/ml, but the effluent milk contained mostly phage-sensitive cells. Analysis of bead populations showed the implantation of the phage as well as a limited population of phage-resistant cells. The effluent biomass from the immobilized cell bioreactor sharply reduced acidifying activity because this biomass was composed mainly of phage-sensitive cells and contained high phage populations.
Key words
Abbreviation key:
D (dilution rate), FCB (free cell bioreactor), ICB (immobilized cell bioreactor), PRC (phage-resistant cells)References
- Diffusion of lactose in kappa-carrageenan/locust bean gum gel beads with or without entrapped growing lactic acid bacteria.Biotechnol. Bioeng. 1991; 38: 1041
- Effect of agitation rate on cell release rate and metabolism during continuous fermentation with entrapped Lactobacillus casei subsp. casei.Biotechnol. Tech. 1992; 6: 265
- Continuous fermentation of a supplemented whey permeate with immobilized Streptococcus salivarius subsp. thermophilus.Int. Dairy J. 1992; 2: 1
- Comportement physiologique et stabilite des cellules immobilisees.Biofutur. 1994; 132: 22
- Growth of yeast contaminants in an immobilized lactic acid bacteria system.Lett. Appl. Microbiol. 1989; 8: 207
- Bacteriophage development in an immobilized lactic acid bacteria system.Biotechnol. Lett. 1988; 10: 463
- Immobilized cell technologies for the dairy industry.CRC Crit. Rev. Biotechnol. 1994; 14: 109
- Resistance of 17 mesophile lactic streptococcal bacteriophages to pasteurization and spray-drying.J. Dairy Res. 1980; 47: 131
Everson, T. C. 1991. Control of the phage in the dairy plant. Page 24 in IDF Bull. 263. Int. Dairy Fed., Brussels, Belgium.
- Progress in dairy starter culture technology.Food Technol. 1984; 38: 41
- Methods for monitoring bacteriophage in cheese factories.Aust. J. Dairy Technol. 1977; 32: 63
- Sources of lactic streptococcal phages in cheese plants.N.Z. J. Dairy Sci. Technol. 1987; 22: 93
- Frequencies of bacteriophage resistant and slow acid-producing variants of Streptococcus cremoris.Appl. Environ. Microbiol. 1983; 45: 1481
- Action of bacteriophages on lactic acid bacteria: consequences and protection.Milk Ind. 1978; 80: 22
- Response to phage infection of immobilized lactococci during continuous acidification and inoculation of skim milk.J. Dairy Res. 1994; 61: 537
- Development of a spiral mesh bioreactor with immobilized lactococci for continuous inoculation and acidification of milk.J. Dairy Sci. 1993; 76: 2856
- Fresh cheese production with continuous pre-fermented milk by a mixed culture of mesophilic lactic streptococci entrapped in Ca-alginate.Biotechnol. Lett. 1987; 9: 789
- Continuous pre-fermentation of milk by entrapped yoghurt bacteria. 1. Development of the process.Milchwissenschaft. 1988; 43: 621
SAS® User's Guide: Statistics, Version 6.08. 1990. SAS Inst., Inc., Cary, NC.
- Immobilized cells: a review of recent literature.Enzyme Microbial Technol. 1987; 9: 66
- Process performance of continuous inoculation and acidification of milk with immobilized lactic acid bacteria.J. Dairy Sci. 1995; 78: 1407
- Calcium alginate-immobilized cultures of lactic streptococci are protected from bacteriophages.J. Dairy Sci. 1987; 70: 1121
Article info
Publication history
Accepted:
January 18,
1996
Received:
July 10,
1995
Identification
Copyright
© 1996 American Dairy Science Association. Published by Elsevier Inc.
User license
Elsevier user license | How you can reuse 
Elsevier's open access license policy
Elsevier user license
Permitted
For non-commercial purposes:
- Read, print & download
- Text & data mine
- Translate the article
Not Permitted
- Reuse portions or extracts from the article in other works
- Redistribute or republish the final article
- Sell or re-use for commercial purposes
Elsevier's open access license policy
