I. GROWTH AND ACID PRODUCTION1

1971 ◽  
Vol 34 (1) ◽  
pp. 30-36 ◽  
Author(s):  
Antonieta Gaddi Angeles ◽  
E. H. Marth
Keyword(s):  
Growth Rates ◽  
Acid Production ◽  
Streptococcus Thermophilus ◽  
Dry Weight ◽  
Lactobacillus Helveticus ◽  
Lactobacillus Delbrueckii ◽  
Cow’S Milk ◽  
Available Nitrogen ◽  
Lactobacillus Pentosus ◽  
Cow's Milk

Soymilk with a protein content similar to that of cow's milk was prepared from soybeans (variety Chippewa 64). Soybeans were washed, soaked until 1 ml of water per gram of beans was absorbed, comminuted with water equivalent to 7.6 times their dry weight, and the mixture filtered through cheese cloth to obtain an aqueous extract free of large particles. Growth rates of 13 species of lactic-acid bacteria in sterile soymilk were generally greater than or comparable to those in cow's milk or Elliker's broth. Acid production in soymilk was not always directly related to growth rates of the organisms. Substantial formation of acid was limited to those bacteria able to utilize the sugars in soymilk, e.g., Streptococcus thermophilus, Lactobacillus delbrueckii, Lactobacillus pentosus, and Leuconostoc mesenteroides. Sources of readily available nitrogen (e.g., protein digests), when added to soymilk, enhanced acid production by S. thermophilus, the Leuconostoc species, and L. pentosus; appeared inhibitory to L. delbrueckii; and had no apparent effect on the other test cultures. Addition of whey powder, glucose, or lactose to soymilk enhanced acid production by Streptococcus lactis, Streptococcus cremoris, Streptococcus diacetilactis, Lactobacillus casei, and Lactobacillus helveticus; whereas addition of sucrose was without benefit. The presence of 0.23–0.25% titratable acid, corresponding to a pH of 5.7, caused coagulation of the sterilized soymilk.

III. LIPOLYTIC ACTIVITY1

1971 ◽  
Vol 34 (2) ◽  
pp. 69-73 ◽  
Author(s):  
Antonieta Gaddi Angeles ◽  
E. H. Marth
Keyword(s):  
Fatty Acids ◽  
Soybean Oil ◽  
Free Fatty Acids ◽  
Lactobacillus Casei ◽  
Streptococcus Thermophilus ◽  
Lactobacillus Brevis ◽  
Lactobacillus Helveticus ◽  
Lactobacillus Delbrueckii ◽  
Lactobacillus Pentosus ◽  
Streptococcus Lactis

The following lactic acid bacteria, when tested with the agar-well method, were able to hydrolyze tributyrin and triolein, but not soybean oil: Streptococcus lactis, Streptococcus cremoris, Streptococcus diacetilactis, Streptococcus thermophilus, Leuconostoc mesenteroides, Pediococcus cerevisiae, Lactobacillus delbrueckii, Lactobacillus casei, Lactobacillus pentosus, and Lactobacillus brevis. Tributyrin only was hydrolyzed by Lactobacillus helveticus. Some free fatty acids were liberated by L. casei, L. delbrueckii, and S. thermophilus in soymilk (1.9% soybean lipids) and in MRS broth fortified with 2.0% soybean oil during a 14-day period of incubation. Although L. casei and L. delbrueckii were more active in soymilk than was S. thermophilus, they released about 10% of the amount of free fatty acids liberated by Candida lipolytica during a similar incubation period.

scholarly journals Selection of raw cow’s milk thermophilic lactic acid bacteria obtained from southwest Parana, Brazil, with potential use as autochthonous starter

2020 ◽  
Vol 23 ◽  
Author(s):  
Simone Beux ◽  
Carla Todescatto ◽  
João Francisco Marchi ◽  
Edimir Andrade Pereira
Keyword(s):  
Starter Culture ◽  
Lactobacillus Rhamnosus ◽  
Streptococcus Thermophilus ◽  
Lactobacillus Helveticus ◽  
Lactobacillus Fermentum ◽  
Cow’S Milk ◽  
Lactobacillus Species ◽  
Cow's Milk ◽  
Specific Pcr ◽  
Raw Cow’S Milk

Abstract This work aimed to isolate and identify Streptococcus and Lactobacillus species from raw cow’s milk obtained from Southwest Paraná - Brazil. We used randomly amplified polymorphic DNA (RAPD)-PCR to identify and type 58Streptococcus and 48 Lactobacillus isolates, of which 04 Streptococcus thermophilus and 02 Streptpcoccus macedonicus were confirmed by species-specific PCR and by sequencing of the 16S ribosomal RNA of 02Streptococcus lutetiensis/infantarius, 10 Lactobacillus fermentum, 03 Lactobacillus delbrueickii subspecies bulgaricus, 01 Lactobacillus rhamnosus/casei and 02 Lactobacillus helveticus. The results indicated predominance of Streptococcus thermophillus and Lactobacillus fermentum. Streptococcus thermophilus and Lactobacillus delbrueickii subspecies bulgaricus strains were tested on the basis of their acidification kinetics. Considerable variation between the Streptococcus thermophilus was observed for the maximum rate of acidification (Vm), with a maximum of -4.5 and minimum of -4.2 pH milliunits min-1. The Lactobacillus delbrueickii subspecies bulgaricus showed values between -8.4 and -7.1 pH milliunits min-1. These results suggest that strains characterized as having a high acidifying capacity, could be used as starters in cheesemaking. The ferments presented an excellent performance in the acidification process, generating adequate curves, characteristics of a starter culture.

scholarly journals THE ROLE OF BERRIES IN QUALITY AND SAFETY ENSURING OF GOAT’S AND COW’S MILK YOGHURT

2021 ◽  
Vol 28 (3) ◽  
pp. 158-174
Author(s):  
Tatiana Cusmenco ◽  
◽  
Elisaveta Sandulachi ◽  
Viorica Bulgaru ◽  
Artur Macari ◽  
...  
Keyword(s):  
Titratable Acidity ◽  
Streptococcus Thermophilus ◽  
Rubus Idaeus ◽  
Point Of View ◽  
Lactobacillus Delbrueckii ◽  
Cow’S Milk ◽  
Cow's Milk ◽  
Physico Chemical ◽  
Pearson Coefficient ◽  
Yeasts And Molds

The yogurt was obtained from a combination of 50% goat's milk and 50% cow's milk with the inclusion of scald fruits of aronia (Aronia melanocarpa), raspberries (Rubus idaeus), strawberry (Fragaria xanassa). Physico-chemical and microbiological indices were determined, according to standard methods, after manufacture and storage, after 1, 5, 10, 15 days. Compared to other samples, yogurt with aronia showed the best values of the dynamics specific to the development of microorganisms: 2.93.107 cfu/ml; the growth rate of lactic acid bacteria at fermentation 0.95 μ; physico-chemical indices: titratable acidity 85 ± 0.078⁰T, pH 4.28 ± 0.002, water activity 0.875 ± 0.025; total dry matter 18.45 ± 0.31%, viscosity 2500 ± 0.023 mPa s, ash content 0.89 ± 0.10% and the optical density 2.531 ± 0.054 nm. Yeasts and molds were not detected in any of the samples. From a physico-chemical point of view, in storage, in all fruit yogurt samples the titratable acidity showed increasing values, pH remaining in the range of permissible values. In storage fruits formed an association to control the microbiological risk and stability of yogurt. Fruit yogurt shows a synergism with Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lactococcus lactis subsp lactis biovar diacetilactis. The overall Pearson coefficient (Pc = f(pH and MC) for all fruit yogurt samples is -0.95066.

Behaviour ofStreptococcus lactisin heat treated (80 °C for 30 min) or sterilized cow's and ewe's milk

1983 ◽  
Vol 50 (3) ◽  
pp. 357-363 ◽  
Author(s):  
Francisco J. Chavarri ◽  
Jose A. Nuñez ◽  
Manuel Nuñez
Keyword(s):  
Acid Production ◽  
Generation Time ◽  
Buffer Capacity ◽  
Cow’S Milk ◽  
Cow's Milk ◽  
Vitamin Content ◽  
Streptococcus Lactis ◽  
Generation Times ◽  
Heat Treated ◽  
Ewe's Milk

SummaryGeneration times and acid production after 6 and 24 h by 20 strains ofStreptococcus lactisof dairy origin were determined in heat treated (80 °C for 30 min) and sterilized cow's and ewe's milk. Ewe's milk enhanced growth of the streptococci, with significantly (P< 0·001) shorter generation times and higher acid production after 6 h incubation than cow's milk, probably due to its higher vitamin content. The stronger buffer capacity of ewe's milk allowed a higher (P< 0·001) acid production after 24 h than cow's milk. A stimulatory effect of sterilization on generation time and acid production after 24 h was observed in cow's milk. However, the heat treated ewe's milk was shown to be a better substrate than sterilized ewe's milk forStr. lactis.

Effect of the addition of extracts of thermophilic lactobacilli on acid production byStreptococcus thermophilusin milk

1981 ◽  
Vol 48 (1) ◽  
pp. 139-148 ◽  
Author(s):  
Denis H. Hemme ◽  
Véronique Schmal ◽  
Jean E. Auclair
Keyword(s):  
Acid Production ◽  
Streptococcus Thermophilus ◽  
Lactobacillus Helveticus ◽  
Caseinolytic Activity ◽  
Hard Cheese

SummarySoluble extracts of 20 strains of thermophilic lactobacilli (Lactobacillus helveticus, L.lactisand L.bulgaricus) were prepared and added to milk for the culture of 10 strains ofStreptococcus thermophilus. Acid production was stimulated in 64·5% of cases for 9 of these 10 strains. The L.helveticusextracts were the most stimulatory, but the same extracts did not always strongly stimulate each strain ofStr. thermophilus. The stimulatory effects observed varied with the volume of extract and the strain ofStr. thermophilus. The exception wasStr. thermophilus385, which was never stimulated. The stimulatory effects observed were due to aminopeptidases present in the lactobacillus extracts and were not related to a general caseinolytic activity. The possible addition of such extracts to milk for cooked hard cheese is discussed.

scholarly journals Biodiversity andγ-Aminobutyric Acid Production by Lactic Acid Bacteria Isolated from Traditional Alpine Raw Cow’s Milk Cheeses

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Elena Franciosi ◽  
Ilaria Carafa ◽  
Tiziana Nardin ◽  
Silvia Schiavon ◽  
Elisa Poznanski ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Random Amplified Polymorphic Dna ◽  
Streptococcus Thermophilus ◽  
Lactobacillus Paracasei ◽  
Aminobutyric Acid ◽  
Cow’S Milk ◽  
Rrna Gene ◽  
Cow's Milk ◽  
Raw Cow’S Milk

“Nostrano-cheeses” are traditional alpine cheeses made from raw cow’s milk in Trentino-Alto Adige, Italy. This study identified lactic acid bacteria (LAB) developing during maturation of “Nostrano-cheeses” and evaluated their potential to produceγ-aminobutyric acid (GABA), an immunologically active compound and neurotransmitter. Cheese samples were collected on six cheese-making days, in three dairy factories located in different areas of Trentino and at different stages of cheese ripening (24 h, 15 days, and 1, 2, 3, 6, and 8 months). A total of 1,059 LAB isolates were screened using Random Amplified Polymorphic DNA-PCR (RAPD-PCR) and differentiated into 583 clusters. LAB strains from dominant clusters (n=97) were genetically identified to species level by partial 16S rRNA gene sequencing. LAB species most frequently isolated wereLactobacillus paracasei,Streptococcus thermophilus, andLeuconostoc mesenteroides. The 97 dominant clusters were also characterized for their ability in producing GABA by high-performance liquid chromatography (HPLC). About 71% of the dominant bacteria clusters evolving during cheeses ripening were able to produce GABA. Most GABA producers wereLactobacillus paracaseibut other GABA producing species includedLactococcus lactis,Lactobacillus plantarum,Lactobacillus rhamnosus,Pediococcus pentosaceus, andStreptococcus thermophilus. NoEnterococcus faecalisorSc. macedonicusisolates produced GABA. The isolate producing the highest amount of GABA (80.0±2.7 mg/kg) was aSc. thermophilus.

Antibiotic susceptibility of different lactic acid bacteria strains

2011 ◽  
Vol 2 (4) ◽  
pp. 335-339 ◽  
Author(s):  
N. Karapetkov ◽  
R. Georgieva ◽  
N. Rumyan ◽  
E. Karaivanova
Keyword(s):  
Cell Wall ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Lactobacillus Acidophilus ◽  
Streptococcus Thermophilus ◽  
Lactobacillus Helveticus ◽  
Lactobacillus Delbrueckii ◽  
Cell Wall Synthesis ◽  
High Susceptibility ◽  
Lactobacillus Delbrueckii Subsp

Five lactic acid bacteria (LAB) strains belonging to species Lactobacillus acidophilus, Lactobacillus helveticus, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus delbrueckii subsp. lactis and Streptococcus thermophilus were tested for their susceptibility to 27 antibiotics. The minimum inhibitory concentrations of each antimicrobial were determined using a microdilution test. Among the strains a high susceptibility was detected for most of the cell-wall synthesis inhibitors (penicillins, cefoxitin and vancomycin) and resistance toward inhibitors of DNA synthesis (trimethoprim/sulfonamides and fluoroquinolones). Generally, the Lactobacillus strains were inhibited by antibiotics such as chloramphenicol, erythromycin and tetracycline at breakpoint levels lower or equal to the levels defined by the European Food Safety Authority. Despite the very similar profile of S. thermophilus LC201 to lactobacilli, the detection of resistance toward erythromycin necessitates the performance of additional tests in order to prove the absence of transferable resistance genes.

scholarly journals Bacterial Community of Grana Padano PDO Cheese and Generical Hard Cheeses: DNA Metabarcoding and DNA Metafingerprinting Analysis to Assess Similarities and Differences

Foods ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1826
Author(s):  
Miriam Zago ◽  
Lia Rossetti ◽  
Tommaso Bardelli ◽  
Domenico Carminati ◽  
Nelson Nazzicari ◽  
...  
Keyword(s):  
Species Abundance ◽  
Streptococcus Thermophilus ◽  
Shannon Index ◽  
Lactobacillus Helveticus ◽  
Lactobacillus Delbrueckii ◽  
Predictive Capacity ◽  
Multivariate Statistical ◽  
Protected Designation Of Origin ◽  
Dna Metabarcoding ◽  
Grana Padano

The microbiota of Protected Designation of Origin (PDO) cheeses plays an essential role in defining their quality and typicity and could be applied to protect these products from counterfeiting. To study the possible role of cheese microbiota in distinguishing Grana Padano (GP) cheese from generical hard cheeses (HC), the microbial structure of 119 GP cheese samples was studied by DNA metabarcoding and DNA metafingerprinting and compared with 49 samples of generical hard cheeses taken from retail. DNA metabarcoding highlighted the presence, as dominant taxa, of Lacticaseibacillus rhamnosus, Lactobacillus helveticus, Streptococcus thermophilus, Limosilactobacillus fermentum, Lactobacillus delbrueckii, Lactobacillus spp., and Lactococcus spp. in both GP cheese and HC. Differential multivariate statistical analysis of metataxonomic and metafingerprinting data highlighted significant differences in the Shannon index, bacterial composition, and species abundance within both dominant and subdominant taxa between the two cheese groups. A supervised Neural Network (NN) classification tool, trained by metagenotypic data, was implemented, allowing to correctly classify GP cheese and HC samples. Further implementation and validation to increase the robustness and improve the predictive capacity of the NN classifier will be needed. Nonetheless, the proposed tool opens interesting perspectives in helping protection and valorization of GP and other PDO cheeses.

scholarly journals Color Stability of Fermented Mare’s Milk and a Fermented Beverage from Cow’s Milk Adapted to Mare’s Milk Composition

Foods ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 217
Author(s):  
Joanna Teichert ◽  
Dorota Cais-Sokolińska ◽  
Romualda Danków ◽  
Jan Pikul ◽  
Sylwia Chudy ◽  
...  
Keyword(s):  
Color Stability ◽  
Titratable Acidity ◽  
Milk Composition ◽  
Water Holding Capacity ◽  
Lactobacillus Delbrueckii ◽  
Cow’S Milk ◽  
Yellowness Index ◽  
Cow's Milk ◽  
And Storage ◽  
Water Holding

Color is important for the consumer when making a purchase decision. Mare’s milk and, thus, fermented mare’s milk is little known to consumers. Thus, it is worth presenting research showing the extent of color change during the production and storage of mare’s milk. Herein, we examined the range of color changes in mare’s milk and cow’s milks adapted to mare’s milk composition. These samples were further fermented and stored for 3 weeks at 5 ± 1 °C. Starter cultures containing Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus were used for fermentation. Mare’s milk reached the required pH of 4.5 during fermentation faster (255 min) than cow’s milk (300 min). After fermentation, mare’s milk compared to cow’s milk and adapted cow’s milk had lower titratable acidity (0.75%) and firmness (145. 6 |(g∙s)|). The water holding capacity (95.6%) and number of Lactobacillus (7.71 log CFU/mL) and Streptocococcus (7.20 log CFU/mL) in mare’s and other’s milks were the same. Mare’s milk was furthest from the ideal white (WI) color, with its chrome (C*) being 1.5-times larger than cow’s milk. However, fermented mare’s milk was darker than the fermented adapted milk and cow’s milk by 36% and 58%, respectively. Storage caused a decrease in the WI, C*, and yellowness index (YI). The fermented mare’s milk color stability during production and storage was less than that of fermented cow’s milk. After 3 weeks storage, it was observed that the titratable acidity increased to 1.05%, and the pH decreased to 4.3 in fermented mare’s milk. The water holding capacity decreased but was still higher compared to fermented cow’s milk.

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