Functional Ingredients from Dairy Fermentations 361ment in the sensory properties of the cheese
due to elevated diacetyl concentrations.
Based on these studies, Lundstedt (1962) pat-
ented the process for application in creaming
the mixture for cottage cheese and for boost-
ing the diacetyl fl avor in cream and Neufchatel
cheeses and butter and margarine.
Later technological advances led to the
use of centrifuges (de - sludge type centri-
fuges) to facilitate the production of highly
concentrated bacterial cultures. With this
advancement frozen concentrated cultures
could be thawed and immediately added to
the chilled creaming mixture for dressing the
chilled cottage cheese curd, with the fl avor
and aroma developing during the refrigerated
holding of the packaged cottage cheese. The
fi rst patent for an application using a highly
concentrated culture of SD was issued to
Sing (1976). The process is widely used by
the dairy industry in the United States.Live Probiotic Cultures
Although probiotic cultures may be consid-
ered as functional cultures, they are treated
separately here because their functionality is
not related to imparting quality attributes
such as body, texture, and fl avor. The func-
tionality of probiotic cultures relates to
adding value to dairy products and imparting
health attributes. The dairy product merely
serves as a vehicle for the delivery of the
desirable health - imparting cultures. Accord-
ing to the United Nations ’ Food and Agri-
culture Organization, “ probiotics are live
microorganisms, which, when administered
in adequate amounts, confer a health benefi t
on the host. ” (Shelke, 2003 ).
There are many benefi ts of regular intake
of probiotics, including alleviating lactose
maldigestion; reducing serum cholesterol;
stimulating immunity; providing antimicro-
bial, antimutagenic, and anticarcinogenic
effects; and maintaining intestinal health
and general well being (Shah, 2000 ). Other
authors have listed additional benefi tsconcentrated culture may be added directly
to the creaming mixture, adjusted to pH 4.3
with citric acid, and the process continued as
described by Babel and Mather (1961).
One of the earliest applications of separate
fl avor bacteria (not part of the starter culture)
in cultured dairy products was promoted by
Lundstedt (1962a,b). In the fi rst paper,
Lundstedt (1962a) described a medium con-
sisting of citrated cottage cheese whey and
pancreatic extract (0.2%) that was found to
support the growth of both Leuconostoc
citrovorum and Cit^ +^ Lactococcus lactis ssp.
lactis (also referred to in the literature as
Lactococcus lactis ssp. lactis biovar diacety-
lactis ; hitherto abbreviated here as SD) to
high cell numbers. In the second paper,
Lundstedt (1962b) , added 0.4% of a citrated
whey culture of SD, which had been grown
for 18 hours at 21 ° C (69.8 ° F) to 224 g of
creamed cottage cheese curd. The cheese was
then held at 3.3 ° C ( 37.9 ° F) for 3 days and
examined. Within 3 days of refrigerated
holding, the cheese had developed a “ typical
well - rounded butter aroma and very pleasant
fl avor. ” He also monitored the diacetyl con-
centrations in cottage cheese, prepared as
described earlier, over 18 days of holding at
refrigerator temperatures. The SD - inoculated
cheese exhibited progressive build - up of
diacetyl concentration up to 10 days, beyond
which there was no change in the diacetyl
concentration up to 18 days. He found a
similar trend with Leuconostoc citravorum,
but the level of diacetyl obtained was lower
than was achieved with SD culture (strain
26 - 2). This was the fi rst quantitative demon-
stration of build - up of diacetyl concentra-
tions at refrigeration temperatures, and it laid
the foundation of further technological devel-
opments in this area.
In the same paper, Lundstedt (1962b)
demonstrated the production of a concen-
trated slurry of SD cells by back fl ushing on
a Seitz fi lter. The use of such concentrated
cells to inoculate chilled, creamed cottage
cheese curd showed considerable improve-