Nondairy Fermented Foods and Products
179
the temperature and pH of the fermentation are well within the growth range of a large number of
undesirable organisms, the safety of products of this type is due to the 30–33% NaCl.
Fish pastes are also common in Southern Asia, but the role of fermenting microorganisms in these
products appears to be minimal. Among the many other fermented fish, fish-paste, and fish-sauce
products, are the following: mam-tom of China; mam-ruoc of Cambodia; bladchan of Indonesia;
shiokara of Japan; belachan of Malaya; bagoong of the Philippines; kapi, hoi-dong, and pla-mam of
Thailand; fessik of Africa; nam-pla , pla-ra, pla-chom, and pla-com of Thailand. A fermented shrimp
product of Thailand is kung-chom.
Soy sauces are fermented condiments of various plant materials. Typically, the plant material first
undergoes a fungal fermentation followed by a brine fermentation in which Tetragenococcus spp. are
active. In Chinese soy sauce only soy beans are used, whereas in Japanese both wheat and soy beans
are used. T. halophilus, which can tolerate 18% NaCl, is active in the brine of the soy sauces noted.
68
Another Tetragenococcus sp., T. muriaticus, has been isolated from fermented squid liver sauce.
72
This species can grow in 1–25% NaCl, and it produces histamine. Some soy sauces are made by acid
hydrolysis of soy beans.
BREADS
San Francisco sourdough bread is similar to sourdough breads produced in various countries.
Historically, the starter for sourdough breads consists of the natural biota of baker’s barm (sour
ferment or mother sponge, with a portion of each inoculated dough saved as starter for the next batch).
The barm generally contains a mixture of yeasts and lactic acid bacteria. In the case of San Francisco
sourdough bread, the yeast has been identified as Saccharomyces exiguus (Candida holmii
80 and the
responsible bacteria are Lactobacillus sanfranciscensis, L. fermentum, L. fructivorans, some L. brevis
strains, and L. pontis.
89 The key bacterium is L. sanfranciscensis, and it preferentially ferments maltose
rather than glucose and it requires fresh yeast extractives and unsaturated fatty acids.
34 The souring
is caused by acids produced by these bacteria, and the yeast is responsible for the leavening action,
although some CO 2 is produced by the bacterial biota. The pH of these sourdoughs ranges from 3.8
to 4.5. Both acetic and lactic acids are produced, with the former accounting for 20–30% of the total
acidity.
40 Lactobacillus paralimentarius is another of the sourdough bacteria.
15
Sourdoughs are placed into three groups and each has its unique fermentation consortium. Type I
sourdoughs are fermented at 20–30
◦ C and the two primary organisms are L. sanfranciscensis and L.
pontis. Type II doughs employ baker’s yeast as a leavening agent, and the dominant lactics are L. pontis, L. panis, and from one to nine other lactobacilli. Type III doughs are dried products of traditional
fermentations (see reference 21). Greek wheat sourdoughs belong to Type I, and the fermentation consortium in the traditional wheat product consists of L. sanfranciscensis, L. brevis, L. paralimentarius,
and Weissella cibaria.
21 Among other organisms found in some sourdough fermentations are Candida
humilis, Dekkera bruxellensis, Saccharomyces cerevisiae, and Saccharomyces uvarum.
Idli is a fermented bread-type product common in southern India. It is made from rice and black
gram mung (urd beans). These two ingredients are soaked in water separately for 3–10 hours and then
ground in varying proportions, mixed, and allowed to ferment overnight. The fermented and raised
product is cooked by steaming and served hot. It is said to resemble a steamed, sourdough bread.
78
During the fermentation, the initial pH of around 6.0 falls to values of 4.3–5.3. In a particular study,
a batter pH of 4.70 after a 20-hour fermentation was associated with 2.5% lactic acid, based on dry
grain weight.
46 In their studies of idli, Steinkraus et al.
78 found total bacterial counts of 10
8 –10
9 /g
after 20–22 hours of fermentation. Most of the organisms consisted of Gram-positive cocci or short
179
the temperature and pH of the fermentation are well within the growth range of a large number of
undesirable organisms, the safety of products of this type is due to the 30–33% NaCl.
Fish pastes are also common in Southern Asia, but the role of fermenting microorganisms in these
products appears to be minimal. Among the many other fermented fish, fish-paste, and fish-sauce
products, are the following: mam-tom of China; mam-ruoc of Cambodia; bladchan of Indonesia;
shiokara of Japan; belachan of Malaya; bagoong of the Philippines; kapi, hoi-dong, and pla-mam of
Thailand; fessik of Africa; nam-pla , pla-ra, pla-chom, and pla-com of Thailand. A fermented shrimp
product of Thailand is kung-chom.
Soy sauces are fermented condiments of various plant materials. Typically, the plant material first
undergoes a fungal fermentation followed by a brine fermentation in which Tetragenococcus spp. are
active. In Chinese soy sauce only soy beans are used, whereas in Japanese both wheat and soy beans
are used. T. halophilus, which can tolerate 18% NaCl, is active in the brine of the soy sauces noted.
68
Another Tetragenococcus sp., T. muriaticus, has been isolated from fermented squid liver sauce.
72
This species can grow in 1–25% NaCl, and it produces histamine. Some soy sauces are made by acid
hydrolysis of soy beans.
BREADS
San Francisco sourdough bread is similar to sourdough breads produced in various countries.
Historically, the starter for sourdough breads consists of the natural biota of baker’s barm (sour
ferment or mother sponge, with a portion of each inoculated dough saved as starter for the next batch).
The barm generally contains a mixture of yeasts and lactic acid bacteria. In the case of San Francisco
sourdough bread, the yeast has been identified as Saccharomyces exiguus (Candida holmii
80 and the
responsible bacteria are Lactobacillus sanfranciscensis, L. fermentum, L. fructivorans, some L. brevis
strains, and L. pontis.
89 The key bacterium is L. sanfranciscensis, and it preferentially ferments maltose
rather than glucose and it requires fresh yeast extractives and unsaturated fatty acids.
34 The souring
is caused by acids produced by these bacteria, and the yeast is responsible for the leavening action,
although some CO 2 is produced by the bacterial biota. The pH of these sourdoughs ranges from 3.8
to 4.5. Both acetic and lactic acids are produced, with the former accounting for 20–30% of the total
acidity.
40 Lactobacillus paralimentarius is another of the sourdough bacteria.
15
Sourdoughs are placed into three groups and each has its unique fermentation consortium. Type I
sourdoughs are fermented at 20–30
◦ C and the two primary organisms are L. sanfranciscensis and L.
pontis. Type II doughs employ baker’s yeast as a leavening agent, and the dominant lactics are L. pontis, L. panis, and from one to nine other lactobacilli. Type III doughs are dried products of traditional
fermentations (see reference 21). Greek wheat sourdoughs belong to Type I, and the fermentation consortium in the traditional wheat product consists of L. sanfranciscensis, L. brevis, L. paralimentarius,
and Weissella cibaria.
21 Among other organisms found in some sourdough fermentations are Candida
humilis, Dekkera bruxellensis, Saccharomyces cerevisiae, and Saccharomyces uvarum.
Idli is a fermented bread-type product common in southern India. It is made from rice and black
gram mung (urd beans). These two ingredients are soaked in water separately for 3–10 hours and then
ground in varying proportions, mixed, and allowed to ferment overnight. The fermented and raised
product is cooked by steaming and served hot. It is said to resemble a steamed, sourdough bread.
78
During the fermentation, the initial pH of around 6.0 falls to values of 4.3–5.3. In a particular study,
a batter pH of 4.70 after a 20-hour fermentation was associated with 2.5% lactic acid, based on dry
grain weight.
46 In their studies of idli, Steinkraus et al.
78 found total bacterial counts of 10
8 –10
9 /g
after 20–22 hours of fermentation. Most of the organisms consisted of Gram-positive cocci or short