176 Modern Food Microbiology
a Pediococcus cerevisiae starter.
19 The product is made by the addition of approximately 3% NaCl
along with sugar, seasoning, and either nitrate, nitrite, or both, to raw cubed beef. The salted beef is
allowed to age at refrigerator temperature for about 10 days during which time the growth of naturally
occurring lactic acid bacteria or the starter organisms are encouraged and Gram negatives are inhibited.
A higher level of microbial activity occurs along with some drying during the smoking step at higher
temperatures. A controlled production process for this product has been studied,
52 and it consists of
aging salted beef at 5
◦ C for 10 days and smoking at 35
◦ C with high relative humidity (RH) for 4 days.
Fermentation may be carried out either by the natural biota of the meat or by the use of a commercial
starter of P. cerevisiae or P. acidilactici. The amount of acidity produced in Lebanon bologna may
reach 0.8–1.2%.
8,57
The hazard of eating improperly prepared, homemade, fermented sausage was indicated by an
outbreak of trichinosis: of the 50 persons who actually consumed the raw summer sausage, 23 fell ill
with trichinosis.
62 The sausage was made on two different days in three batches according to a family
recipe that called for smoking at cooler smoking temperatures, believed to produce a better-flavored
product. All three batches of sausages contained home-raised beef. In addition, two batches eaten by
victims contained pork inspected by the U.S. Department of Agriculture (USDA) in one case and
home-raised pork in the other, but Trichinella spiralis larvae were found only in the USDA-inspected
pork. This organism can be destroyed by a heat treatment that results in internal temperatures of at
least 60
◦ C or 140
◦ F (see Chapter 29).
In the production of dry sausages, lactobacilli produce aminopeptidases that aid in the generation of
amino acids from sausage proteins. The amino acids contribute to the overall flavor of dry sausages.
In the case of Lactobacillus sakei, it produces decarboxylases that give rise to biogenic amines, and
these compounds can inhibit aminopeptidases and thus reduce flavor enhancement in dry-fermented
sausages (see reference 71).
Fermented sausages produced without the use of starters have been found to contain large numbers
of lactobacilli such as L. plantarum.
20 The use of a P. cerevisiae starter leads to the production of
a more desirable product.
19,36 In their study of commercially produced fermented sausages, Smith
and Palumbo
77 found total aerobic plate counts to be in the 10
7 –10
8 /g range, with a predominance
of lactic acid types. When starter cultures were used, the final pH of the products ranged from 4.0 to
4.5, whereas those produced without starters ranged between 4.6 and 5.0. For summer-type sausages,
pH values of 4.5–4.7 have been reported for a 72-hour fermentation.
2 These investigators found that
fermentation at 30
◦ C and 37
◦ C led to a lower final pH than at 22
◦ C and that the final pH was directly
related to the amount of lactic acid produced. The pH of fermented sausage may actually increase
by 0.1 or 0.2 unit during long periods of drying due to uneven buffering produced by increases in
the amounts of basic compounds.
90 The ultimate pH attained following fermentation depends on the
type of sugar added. Although glucose is most widely used, sucrose has been found to be an equally
effective fermentable sugar for low pH production.
1 The effect of a commercial frozen concentrate
starter (P. acidilactici) in fermenting various sugars added to a sausage preparation is illustrated in
Figure 8–1. Lactobacillus gasseri, when employed in a meat fermentation was shown to prevent
enterotoxin formation by Staphylococcus aureus in a model sausage preparation.
6 This species was
the most effective of five other Lactobacillus species.
Prior to the late 1950s, the production of fermented sausages was facilitated by either back inoculations, or a producer took the chance of the desired organisms being present in the raw materials. Until
recently, the manufacture of these, as well as of many other fermented foods, has been more of an art
than a science. With the advent of pure culture starters, not only has production time been shortened,
but more uniform and safer products can be produced.
25 Although the use of starter cultures has been
a Pediococcus cerevisiae starter.
19 The product is made by the addition of approximately 3% NaCl
along with sugar, seasoning, and either nitrate, nitrite, or both, to raw cubed beef. The salted beef is
allowed to age at refrigerator temperature for about 10 days during which time the growth of naturally
occurring lactic acid bacteria or the starter organisms are encouraged and Gram negatives are inhibited.
A higher level of microbial activity occurs along with some drying during the smoking step at higher
temperatures. A controlled production process for this product has been studied,
52 and it consists of
aging salted beef at 5
◦ C for 10 days and smoking at 35
◦ C with high relative humidity (RH) for 4 days.
Fermentation may be carried out either by the natural biota of the meat or by the use of a commercial
starter of P. cerevisiae or P. acidilactici. The amount of acidity produced in Lebanon bologna may
reach 0.8–1.2%.
8,57
The hazard of eating improperly prepared, homemade, fermented sausage was indicated by an
outbreak of trichinosis: of the 50 persons who actually consumed the raw summer sausage, 23 fell ill
with trichinosis.
62 The sausage was made on two different days in three batches according to a family
recipe that called for smoking at cooler smoking temperatures, believed to produce a better-flavored
product. All three batches of sausages contained home-raised beef. In addition, two batches eaten by
victims contained pork inspected by the U.S. Department of Agriculture (USDA) in one case and
home-raised pork in the other, but Trichinella spiralis larvae were found only in the USDA-inspected
pork. This organism can be destroyed by a heat treatment that results in internal temperatures of at
least 60
◦ C or 140
◦ F (see Chapter 29).
In the production of dry sausages, lactobacilli produce aminopeptidases that aid in the generation of
amino acids from sausage proteins. The amino acids contribute to the overall flavor of dry sausages.
In the case of Lactobacillus sakei, it produces decarboxylases that give rise to biogenic amines, and
these compounds can inhibit aminopeptidases and thus reduce flavor enhancement in dry-fermented
sausages (see reference 71).
Fermented sausages produced without the use of starters have been found to contain large numbers
of lactobacilli such as L. plantarum.
20 The use of a P. cerevisiae starter leads to the production of
a more desirable product.
19,36 In their study of commercially produced fermented sausages, Smith
and Palumbo
77 found total aerobic plate counts to be in the 10
7 –10
8 /g range, with a predominance
of lactic acid types. When starter cultures were used, the final pH of the products ranged from 4.0 to
4.5, whereas those produced without starters ranged between 4.6 and 5.0. For summer-type sausages,
pH values of 4.5–4.7 have been reported for a 72-hour fermentation.
2 These investigators found that
fermentation at 30
◦ C and 37
◦ C led to a lower final pH than at 22
◦ C and that the final pH was directly
related to the amount of lactic acid produced. The pH of fermented sausage may actually increase
by 0.1 or 0.2 unit during long periods of drying due to uneven buffering produced by increases in
the amounts of basic compounds.
90 The ultimate pH attained following fermentation depends on the
type of sugar added. Although glucose is most widely used, sucrose has been found to be an equally
effective fermentable sugar for low pH production.
1 The effect of a commercial frozen concentrate
starter (P. acidilactici) in fermenting various sugars added to a sausage preparation is illustrated in
Figure 8–1. Lactobacillus gasseri, when employed in a meat fermentation was shown to prevent
enterotoxin formation by Staphylococcus aureus in a model sausage preparation.
6 This species was
the most effective of five other Lactobacillus species.
Prior to the late 1950s, the production of fermented sausages was facilitated by either back inoculations, or a producer took the chance of the desired organisms being present in the raw materials. Until
recently, the manufacture of these, as well as of many other fermented foods, has been more of an art
than a science. With the advent of pure culture starters, not only has production time been shortened,
but more uniform and safer products can be produced.
25 Although the use of starter cultures has been