FSTA Vol. 21 (1989) No. 2 (Abstr. No. 2 P 67)
[Microscopic studies of the microflora of kefir grains and of kefir
made by different methods]Duitschaever, C.L.; Kemp, N.; Smith, A. K.
Michwissenschft 43 (8) 479-481 (1988) [10 ref. En, de, fr] [Dep. of
food Sci., Univ. of Guelph, Guelph, Ont. N1G 2W1, Canada]
Scanning electron microscopy of commercial kefir grains showed the
presence of short and elongated bacilli (probably Lactobacilli) and
yeasts embedded amongst a densely packed, fibrillar amorphous matrix, but
no cocci were evident. The appearance of some long and curved bacteria
in a surface section of the grains suggested that the microflora at the
edge of the grains might differ from that near the center.
Composition of the kefir microflora varied with method of production
as follows: that made with pure cultures of lactobacilli, streptococci
and yeasts showed presence of all 3 organisms; that made with direct-set
culture contained cocci and few yeasts, and had a buttermilk-like character
with slight effervescence; kefir made with grain-free starter contained
only cocci and had a pronounced buttermilk flavour.
CDP
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FSTA Vol. 11 (1979) No. 07 (Abstr. No. 7 P 1255)
[Kefir microorganisms: lactic acid bacteria.]
Rosi, J.; Rosi,J.
Snienza e Tecnica Lattiero-Cassearia 29 (5) 291-305 (1978) [33 ref. It, en]
[Istituto di Microbiol. Lattiero-Cassearia Univ., Perugia, Italy]
Streptococci isolated from liquid kefir were identified and the basis of
morphological and biochemical characteristics as Str. Durans (1,000,000 per ml.).
They were not found in the kefir grains. Lactobacilli which did not produce
extracellular polysaccharides as determined by the method of Raibaud et al.
[Journal of Applied Bacteriology (1961) 24, 285], appeared to be of the species
Lb. brevis, which counts of 1,000, /gm both in the grains and in the liquid kefir.
Capsulated lactobacilli isolated had some characteristics suggesting that they
were not typical members of this group. Capsulated leuconostocs found both in
the grains and liquid kefir (100,000 /gm or ml) were identified as Leuc.
mesenteroids.
ADL
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FSTA Vol. 7 (1975) No 09 (Abst. No. 9 P 2030)
[Microbiology and chemical composition and ultrastructure of kefir grains]
Ottogalli, G. ; Galli, A. ; Resmini, P. ; Volonterio, G.
Annali di Microbioligia ed Enzimologia 23 (4/5/6) 109-121 (1973) [16 ref. It. en]
[Instituti di Microbiol. Agraria e Ind Agrarie, Univ. di Milano, Mila, Italy]
4 Samples of kefir grains from Russia, Bulgaria and Yugoslavia (2) were
found to have somewhat similar compositions, averaging 10.3% dry matter
(DM) of which 3.5% was fat, 32.6% protein, 6% ash, and 56.2% carbohydrate
material, nearly one-half of which was composed of a polysaccharide yielding
glucose and galactose on hydrolysis. The microflora present included the
lactic acid bacteria Streptococcus lactis, Lactobacillus. brevis, L. acidophilus
and Leuconostoc kefir (1 sample) and the yeasts Saccharomyces lactis, Sacc,
carlsbergensis, Candida tunuis, and Cand. Pseudotropicalis. Other organisms,
occurring in isolated samples, were Acetobacter rancens, and Bacillus subtilis.
Structure, as revealed by microscopy and electron microscopy, showed the various
organisms embedded in the material of the grains. L. acidophilus appears to be
responsible for formation of the capsular polysaccharide which confers elastic
properties on the grains.
GTP
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FSTA Vol. 11 (1979) No. 04 (Abstr. No. 4 P 632)
[Kefir micro-organisms: yeasts.]
Rosi, J.
Scienza e Tecnica Lattiero-Casearia 29 (2) 59-67 (1978) [30 ref. It. en]
[Istituto di Microbiol. Lattiero-Casearia, Univ., Perugia, Italy]
2 types of kefir were analyzed, as well as the kefir grains, which
were first washed for 12 h, then broken up and diluted in decimal series.
The yeasts were isolated on Difco WL medium at 28� C and identified according
to the system proposed by Lodder [Yeast: taxonomic study, North-Holland Publishing
Co., Amsterdam, 1970]. Both in the grains and in the liquid kefir, saccharomyces
delbruekii appeared to be the dominant yeast (66%), accompanied by C. cerevisiae.
Yeast counts were about 100,000/ml in the liquid and 1,000,000/g in the grains.
Study of stained sections of the grains under the microscope indicated that the
yeasts were located mainly on the edge of the internal cavities and occasionally
along the peripheral channels, whereas the exterior was occupied mainly by bacteria.
The relationship between the yeasts and bacteria is discussed.
ADL
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FSTA Vol. 11 (1979) No. 04 (abstr. No. 4 P 633
[Kefir micro-organisms: acetic acid bacteria]
Rosi, J.
Scienza e Tecnica Lattiero-Casearia 29 (4) 221-227 (1978) [11 ref. It. en]
[Istituto di Microbiol. Lattiero-Casearia, Univ., Perugia, Italy]
96 cultures of catalase-positive, Gram-negative aerobic bacteria were isolated
from the liquid kefir and kefir grains described in the preceding abstr.; 12
cultures, which did not utilize ethanol to acetic acid at pH 4.5, were classed as
Pseudomonas spp. The remaining 84 cultures were identified as Acetobacter aceti,
although 24 of them produced gluconic acid (a parameter which, according to some
authors, is characteristic of Gluconobacter spp.). Of the 84 cultures, 30 were
isolated from the grains and 54 from the liquid kefir. Counts were about 1,000/ml
in the liquid kefir and 100/g in the grains.
ADL
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FSTA Vol. 16 (1984) No. 12 (abstr. No. 12 P 2642)
[A note on the heterofermentative Lactobacillus isolated from kefir grains]
Marshall, V. M.; Cole, W. M.; Farrow, J. A. E.
Journal of applied Bacteriology 56 (3) 503-505 (1984) [12 ref, En] [Nat.
Inst, for Res. in Dairying, Shingfield, Reading RG2(AT, UK]
Several heterofermentative strains of lactobacilli were isolated from kefir
grains from 4 different sources, and were compared with the reference strains
Lactobacillus caucasicus [L. kefir] NCDO 190 and L. brevis NCDO 1749 (type strain).
All strains grew in 15% ethanol, produced NH3 from arginine,
grew at 15� but not at 45� C, and produced DL-lactic acid. Isolates LK22, LK24 LK25,
LK3, LK5 fermented only arabinose, ribose and gluconate, and did not hydrolyze
oligosaccharides. Strain LK0 utilized only one disaccharide (maltose) and others
utilized maltose, lactose and melibiose. In view of these characteristics, and the
fact that the isolates showed high DNA-DNA homology (ranging from 85 to 109%) with
strain NCDO 190, and only 32% homology with L. brevis NCDO 1749, it is concluded
that isolates belong to the species L. kefir.
JMA
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FSTA Vol. 19 (1987) No. 5. Abstr. No. 5 P 190
[Microbiological processes in folacin synthesis in kefir.]
Drewek, Z.; Czarnocka-Roczniokowa, B.
Acta Alimentaria Polonica 12 (1) 39-45 (1986) [17 ref. En, pl]
[Dep. of food Eng. & Biotch., Argric. & Tch. Uni., Olsztyn Poland]
During manufacture of 3 batches of kefir, folacin activity (FA) (micro-g/100g
decreased from about 2.5 in raw milk to about 2.0 after pasteurization, then
increasedto 4.3 in fresh kefir (incubated for 24 h @ 22�C). On subsequent storage
FA increased to 6.3 micro-g/100g after 24 h @ 18�C and to 8.2 and 9.3 micro-g/100g
after 24 and 48 h respectively @ 4�C; further storage at 4�C had little additional
effect on FA.
When kefir was made from grains with yeast;lactic acid bacteria ratios 1:5.6, 1:15
(traditional culture) and 1:46, increasing or decreasing the proportion of yeast in
the grains resulted in flavour defects. Although kefir made with traditional grains
had the lowest FA in the fresh product, it exhibited the highest rate of folacin
biosynthesis during storage, FA increasing by 116.2% during storage for 48 h @ 4�C
CDP
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FSTA Vol. 16 (1984) No. 2. (Abstr. No. 2 P 436)
[Identification and fermentation of kefir yeast.]
Iwasawa, S.; Ueda, M.; Miyata, N.; Hirota, T; Ahiko, K.
Agricultural and biological Chemistry 46 (11) 2631-2636 (1982) [14 ref. En] [Tech.
Res. Inst., Snow Brand Milk Products Co. Ltd., 1-2 Minamidai 1-chrome, Kawagoe, Saitama
350 Japan]
A yeast identified as Torulopsis holmii was isolated from kefir grains obtained
from Christian Hansens's Laboratory, Denmark, and grown in skim milk at 20�C for 5
days. It fermented glucose, galactose, mannose and sucrose, but not lactose. An inductive
period was required for fructose fermentation. In a glucose/galactose medium the yeast
preferentially metabolized galactose. Respirometric analysis in Warburg vessels suggested
that galactose metabolism followed Leloir's pathway but enzymes involved in sugar uptake
and metabolism were quite different from those usually found in yeasts.
ADL
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FSTA Vol. 3 No. 8. (Abstr. No. 8 P 1364)
[Quantative characteristics of the microflora of kefir cultures.]
Babina, N. A.
Molochnaya Promyshlennost' 32 (2) 18-19 (1971) [Ru] [Vses. Nauchno-issled. Inst.
Molochnoi Promyshlennosti. Moscow, USSR]
Commercial kefir grains were cultured by the established procedure of the
All-Union Dairy Industry Research Institute and the microbial composition of
the culture was determined 2 X during ripening and 1 X during storage of the
ripe culture. Contents of (i) mesophilic lactic streptococci (Str. lactis),
(ii) aroma forming streptococci (Str. paracitrovorus, Leuconostoc dextranicum),
(iii) acetic acid bacteria, (iv) yeasts, and (v) thermophilic lactobacilli in
1 ml ripe culture were of the order of;
(i) 100,000,000 - 1,000,000,000
(ii) 10,000,000 - 1,000,000,000
(iii)100,000 - 1,000,000
(iv) 100,000 - 1,000,000
(v) 100,000 - 1,000,000.
Streptobacteria and betabacteria did not exceed a few hundred/ml.
SKK
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FSTA Vol. 10 (1978) No. 10 Abstr. # 10 P 1711
[Chemical changes during fermentation and ripening of kefir.]
Gawel, J. ; Gromadka, M.
XX International Dairy Congress E, 839-840 (1978) [3 ref. En] [Univ. of
Agric., Warsaw, Poland]
Kefir was made from milk with 1.5% fat under laboratory conditions. The
laboratory kefir after 2 days ripening at 8-10 deg. C had pH 4.31, acidity
0.82% lactic acid, lactose 3.69%, orotic acid 35.3 mg/l., acetaldehyde
0.99-1.70 mg/l., diacetyl 0-2.90 mg/l., acetoin 0.82-11.74% mg/l., citric
acid 18.8 mg/l., and ethanol 0.029%
JMD
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FSTA Vol. 5 (1973) No. 12 Abstr. # 12 P 1795
[Quantative composition of kefir grains and kefir microflora at different
times of the year.]
Babina, N A.; Rozhkova, I. V
Molochnaya Promyshlennost' No. 2, 15-17 (1973) [Ru] [ses. Nauchno-issled.
Inst. Molochnoi Promyshlennosti, Moscow, [USSR]
Month-to-month fluctuations in the microflora of kefir grains and kefir were
studied. In kefir grains, mesophilic lactic streptococci, yeasts and
aroma-forming streptococci changed little during the year; acetic acid
bacteria showed higher values in winter months and thermophilic lactobacilli
were most numerous in spring and summer. Changes in kefir microflora were
similar to those in the kefir grains.
SKK
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