TY - JOUR
T1 - Invited review
T2 - Starter lactic acid bacteria survival in cheese: New perspectives on cheese microbiology
AU - Wilkinson, Martin G.
AU - LaPointe, Gisèle
N1 - Publisher Copyright:
© 2020 American Dairy Science Association
PY - 2020/12
Y1 - 2020/12
N2 - The importance of starter cultures to cheese manufacture and ripening is well known. Starters are inoculated into cheese milk at a level of ∼106 cfu/mL either from a bulk culture or using commercial direct-to-vat cultures. Before ripening, starters grow in the milk to reach populations of 107 to 109 cfu/g of curd depending on processing variables such as cook temperature, inclusion of washing steps, degree of partitioning with curds and whey, and importantly salt addition rate. Inherent strain-related properties also determine final populations in the curd following manufacture and include temperature sensitivity, salt sensitivity, presence of prophage, autolytic and permeabilization properties (which are influenced by processing steps), presence and type of cell envelope proteinase, and metabolic activity. Ripening of important industrial cheese varieties such as Cheddar, Dutch, Swiss, and Italian-type cheese varieties is characterized by extended storage under temperature-controlled conditions enabling characteristic flavor and texture development to occur. Over ripening, microbiological, biochemical and enzymatic changes occur with a decline in starter viability, release of intracellular enzymes, hydrolysis of proteins, carbohydrates and lipids, and formation of a range of volatile and nonvolatile flavor components. Recent reports suggest that starter strains may be present during the later stages of ripening and therefore their potential role needs to be reconsidered. This review will focus on our current understanding of starter viability and vitality during cheese ripening and will also review the area of starter permeabilization, autolysis, and enzyme release.
AB - The importance of starter cultures to cheese manufacture and ripening is well known. Starters are inoculated into cheese milk at a level of ∼106 cfu/mL either from a bulk culture or using commercial direct-to-vat cultures. Before ripening, starters grow in the milk to reach populations of 107 to 109 cfu/g of curd depending on processing variables such as cook temperature, inclusion of washing steps, degree of partitioning with curds and whey, and importantly salt addition rate. Inherent strain-related properties also determine final populations in the curd following manufacture and include temperature sensitivity, salt sensitivity, presence of prophage, autolytic and permeabilization properties (which are influenced by processing steps), presence and type of cell envelope proteinase, and metabolic activity. Ripening of important industrial cheese varieties such as Cheddar, Dutch, Swiss, and Italian-type cheese varieties is characterized by extended storage under temperature-controlled conditions enabling characteristic flavor and texture development to occur. Over ripening, microbiological, biochemical and enzymatic changes occur with a decline in starter viability, release of intracellular enzymes, hydrolysis of proteins, carbohydrates and lipids, and formation of a range of volatile and nonvolatile flavor components. Recent reports suggest that starter strains may be present during the later stages of ripening and therefore their potential role needs to be reconsidered. This review will focus on our current understanding of starter viability and vitality during cheese ripening and will also review the area of starter permeabilization, autolysis, and enzyme release.
KW - autolysis
KW - cheese
KW - enzymes
KW - permeabilization
KW - ripening
KW - starters
UR - http://www.scopus.com/inward/record.url?scp=85092010304&partnerID=8YFLogxK
U2 - 10.3168/jds.2020-18960
DO - 10.3168/jds.2020-18960
M3 - Review article
C2 - 33010919
AN - SCOPUS:85092010304
SN - 0022-0302
VL - 103
SP - 10963
EP - 10985
JO - Journal of Dairy Science
JF - Journal of Dairy Science
IS - 12
ER -