Nondairy Fermented Foods and Products
181
The olive fermentation is preceded by a treatment of green olives with 1.6 to 2.0% lye, depending
on the type of olive, at 21–25
◦ C for 4–7 hours for the purpose of removing some of the bitter principal.
Following the complete removal of lye by soaking and washing, the green olives are placed in oak
barrels and brined so as to maintain a constant 28
◦ –30
◦ salinometer level. Inoculation with L. plantarum
may be necessary because of destruction of organisms during the lye treatment. The fermentation may
take as long as 6–10 months, and the final product has a pH of 3.8–4.0 following up to 1% lactic acid
production.
Among the types of microbial spoilage that olives undergo, one of the most characteristic is zapatera
spoilage. This condition, which sometimes occurs in brined olives, is characterized by a malodorous
fermentation. The odor is due apparently to propionic acid, which is produced by certain species of
Propionibacterium.
61 In addition to propionic acid, formic, butyric, succinic, isobutyric, n-valeric,
and cyclohexacarbolic acids, as well as methanol, ethanol, 2-butanol, and n-butanol may be produced
(see reference 31).
A softening condition of Spanish-type green olives has been found to be caused by the yeasts
Rhodotorula glutinis var. glutinis, R. minuta var. minuta, and R. rubra.
88 All of these organisms produce polygalacturonases, which effect olive tissue softening. Under appropriate cultural contions, the
organisms were shown to produce pectin methyl esterase as well as polygalacturonase. A sloughing
type of spoilage of California ripe olives was shown by Patel and Vaughn
55 to be caused by Cellulomonas flavigena. This organism showed high cellulolytic activity, which was enhanced by the
growth of other organisms such as Xanthomonas, Enterobacter, and Escherichia spp.
The production of some biogenic amines has been shown to occur primarily in Spanish-style
green olives during the brining process.
32 The amines found were cadaverine, histamine, tyramine,
tryptamine, and putrescine with the latter being in highest concentration after 3 months of brining.
The others were found in samples taken after 12 months.
32
Pickles
Pickles are fermentation products of fresh cucumbers, and as is the case for sauerkraut production, the
starter culture generally consists of the normal mixed biota of cucumbers. In the natural production of
pickles, the following lactic acid bacteria are involved in the process in order of increasing prevalence:
L. mesenteroides, E. faecalis, P. cerevisiae, L. brevis, and L. plantarum. Of these, the pediococci and
L. plantarum are the most involved, with L. brevis being undesirable because of its capacity to produce
gas. L. plantarum is the most essential species in pickle production, as it is for sauerkraut.
In the production of pickles, selected cucumbers are placed in wooden brine tanks with initial brine
strengths as low as 5% NaCl (20
◦ salinometer). Brine strength is increased gradually during the course
of the 6- to 9-week fermentation, until it reaches around 60
◦ salinometer (15.9% NaCl). In addition
to exerting an inhibitory effect on the undesirable Gram-negative bacteria, the salt extracts water and
water-soluble constituents from the cucumbers, such as sugars, which are converted by the lactic acid
bacteria to lactic acid. The product that results is a salt-stock pickle from which pickles such as sour,
mixed sour, chowchow, and so forth may be made.
The general technique of producing brine-cured pickles has been in use for many years, but it often
leads to serious economic loss because of pickle spoilage from such conditions as bloaters, softness,
off-colors, and so on. The controlled fermentation of cucumbers brined in bulk has been achieved, and
this process not only reduces economic losses of the type noted, but leads to a more uniform product
over a shorter period of time. The controlled fermentation method employs a chlorinated brine of
25
◦ salinometer, acidification with acetic acid, the addition of sodium acetate, and inoculation with
181
The olive fermentation is preceded by a treatment of green olives with 1.6 to 2.0% lye, depending
on the type of olive, at 21–25
◦ C for 4–7 hours for the purpose of removing some of the bitter principal.
Following the complete removal of lye by soaking and washing, the green olives are placed in oak
barrels and brined so as to maintain a constant 28
◦ –30
◦ salinometer level. Inoculation with L. plantarum
may be necessary because of destruction of organisms during the lye treatment. The fermentation may
take as long as 6–10 months, and the final product has a pH of 3.8–4.0 following up to 1% lactic acid
production.
Among the types of microbial spoilage that olives undergo, one of the most characteristic is zapatera
spoilage. This condition, which sometimes occurs in brined olives, is characterized by a malodorous
fermentation. The odor is due apparently to propionic acid, which is produced by certain species of
Propionibacterium.
61 In addition to propionic acid, formic, butyric, succinic, isobutyric, n-valeric,
and cyclohexacarbolic acids, as well as methanol, ethanol, 2-butanol, and n-butanol may be produced
(see reference 31).
A softening condition of Spanish-type green olives has been found to be caused by the yeasts
Rhodotorula glutinis var. glutinis, R. minuta var. minuta, and R. rubra.
88 All of these organisms produce polygalacturonases, which effect olive tissue softening. Under appropriate cultural contions, the
organisms were shown to produce pectin methyl esterase as well as polygalacturonase. A sloughing
type of spoilage of California ripe olives was shown by Patel and Vaughn
55 to be caused by Cellulomonas flavigena. This organism showed high cellulolytic activity, which was enhanced by the
growth of other organisms such as Xanthomonas, Enterobacter, and Escherichia spp.
The production of some biogenic amines has been shown to occur primarily in Spanish-style
green olives during the brining process.
32 The amines found were cadaverine, histamine, tyramine,
tryptamine, and putrescine with the latter being in highest concentration after 3 months of brining.
The others were found in samples taken after 12 months.
32
Pickles
Pickles are fermentation products of fresh cucumbers, and as is the case for sauerkraut production, the
starter culture generally consists of the normal mixed biota of cucumbers. In the natural production of
pickles, the following lactic acid bacteria are involved in the process in order of increasing prevalence:
L. mesenteroides, E. faecalis, P. cerevisiae, L. brevis, and L. plantarum. Of these, the pediococci and
L. plantarum are the most involved, with L. brevis being undesirable because of its capacity to produce
gas. L. plantarum is the most essential species in pickle production, as it is for sauerkraut.
In the production of pickles, selected cucumbers are placed in wooden brine tanks with initial brine
strengths as low as 5% NaCl (20
◦ salinometer). Brine strength is increased gradually during the course
of the 6- to 9-week fermentation, until it reaches around 60
◦ salinometer (15.9% NaCl). In addition
to exerting an inhibitory effect on the undesirable Gram-negative bacteria, the salt extracts water and
water-soluble constituents from the cucumbers, such as sugars, which are converted by the lactic acid
bacteria to lactic acid. The product that results is a salt-stock pickle from which pickles such as sour,
mixed sour, chowchow, and so forth may be made.
The general technique of producing brine-cured pickles has been in use for many years, but it often
leads to serious economic loss because of pickle spoilage from such conditions as bloaters, softness,
off-colors, and so on. The controlled fermentation of cucumbers brined in bulk has been achieved, and
this process not only reduces economic losses of the type noted, but leads to a more uniform product
over a shorter period of time. The controlled fermentation method employs a chlorinated brine of
25
◦ salinometer, acidification with acetic acid, the addition of sodium acetate, and inoculation with