EFFECT OF INCUBATION TEMPERATURE ON ACID AND FLAVOR PRODUCTION IN MILK BY LACTIC ACID BACTERIA1

1972 ◽  
Vol 35 (4) ◽  
pp. 242-244 ◽  
Author(s):  
S. M. Dutta ◽  
R. K. Kuila ◽  
B. C. Arora ◽  
B. Ranganathan
Keyword(s):  
Lactobacillus Casei ◽  
Incubation Temperature ◽  
Titratable Acidity ◽  
Streptococcus Thermophilus ◽  
Starter Cultures ◽  
Lactobacillus Helveticus ◽  
Volatile Acidity ◽  
Significant Difference ◽  
Acetoin Production ◽  
Incubation Temperatures

The effect of incubation temperature on acid and flavor production by 8 lactic starter cultures was studied. Higher titratable acidity was produced at 22 than at 30 C by Streptococcus cremoris, while a reverse trend was observed with Streptococcus diacetilactis. With Streptococcus thermophilus, Lactobacillus casei, and Lactobacillus helveticus, increasing the incubation temperature from 37 to 42 C retarded acid production by 8.54, 31.8, and 37.4%, respectively. Volatile acidity increased at higher incubation temperatures in some cultures, while in others, a significant decrease was observed. Higher diacetyl production was noted when S. diacetilactis was incubated at 22 C, as compared to 30 C, while the reverse occurred with S. thermophilus. Acetoin production by S. diacetilactis was enhanced 7-fold by increasing the incubation temperature from 22 to 30 C. No significant difference was noted in proteolytic activity of all cultures, regardless of incubation temperature.

scholarly journals Development of a Culture-ripened Semi-hard Kishk-cheese Containing Bourghol or Semolina

2018 ◽  
Vol 8 (1) ◽  
pp. 21
Author(s):  
Elham Hajj ◽  
Rita Yaacoub ◽  
Nadine Al-Arja ◽  
Samir Scandar ◽  
Hussein Dib
Keyword(s):  
Physicochemical Parameters ◽  
Sharp Increase ◽  
Free Amino ◽  
Marked Decrease ◽  
Titratable Acidity ◽  
Starter Cultures ◽  
Oxidation Rates ◽  
Significant Difference ◽  
Depletion Rate ◽  
Tbars Values

In order to develop a new Kishk-based ripened semi-hard cheese, two different wheat types, namely Bourghol and Semolina, were used. The process involved adding together cereal, goat strained yogurt, starter cultures and rennin enzyme. Physicochemical parameters and sensory attributes were assessed during 4 weeks of ripening at 10°C. The results showed an increase in titratable acidity, pH and solubility index in both types of cheese over ripening period reaching final levels of 1.95%, 3.75 and 85% respectively. Free amino acids were accumulating in Semolina cheese (17.75 mg Leu/g in final product), with a sharp increase after week 2 concurring with a marked decrease in residual lactose. A higher depletion rate of residual lactose was observed for Semolina cheese (49% in Semolina vs 40% in Bourghol) (p<0.05), reflecting better utilization of lactose by LAB. Both types of cheese showed limited oxidation rates (low peroxide and TBARS values) and balanced lipolysis, where FFA formed by the latter decreased after week 2. Texture analysis showed that Kishk-cheese made using Bourghol was always harder (p<0.05) than that of Semolina. Sensory analysis showed that cheese obtained from Bourghol tends to be more yellowish, harder with closed and crumbly body, together with a grainy texture in mouth and pronounced cereal flavor, whereas cheese obtained from Semolina tends to be sour, creamy with a sticky and cohesive texture, and rich lactic, buttery and cheesy flavors. Hedonic tests showed a significant difference (p<0.05) in preference between both types of cheese where Semolina was always preferred except for odor.

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 Importância das Bactérias Ácido Láticas e não Starter (NSLAB) na Tecnologia de Produção dos Derivados Lácteos

2020 ◽  
Vol 24 (4) ◽  
pp. 348-352
Author(s):  
Maria Tereza Pereira ◽  
Elsa Helena Walter de Santana ◽  
Joice Sifuentes dos Santos
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Lactococcus Lactis ◽  
Lactobacillus Casei ◽  
Streptococcus Thermophilus ◽  
Raw Milk ◽  
Fermented Milk ◽  
Starter Cultures ◽  
Bacillus Spp ◽  
Lactobacillus Spp

Produtos lácteos fermentados contêm bactérias ácido lácticas (BAL), naturalmente presentes ou adicionadas na matriz láctea como culturas iniciadoras (starters), contribuindo com aroma, textura, valor nutricional e segurança microbiológica. Lactobacillus spp., Streptococcus spp., Lactococcus spp. e Leuconostoc spp. são utilizados como culturas starters em laticínios. As BAL podem ser classificadas em mesofílicas (ex Lactococcus lactis) e termofílicas (ex Streptococcus thermophilus), e de acordo com seus metabólitos de fermentação em homofermentativas (ácido lático) e heterofermentativas (ácido lático, dióxido de carbono, diacetil e outros compostos flavorizantes). Entre as BAL há um grupo de bactérias lácticas que não fazem parte da cultura láctica (non starter lactic acid bacteria - NSLAB), que são oriundas do leite cru, do ambiente de ordenha ou da indústria formando biofilmes. As NSLAB são representadas por espécies heterofermentativas de lactobacilos mesofílicos como Lactobacillus casei spp., L. paracasei spp., L. rhamnosus spp. e L. plantarum spp., e ainda por Pediococcus spp., Leuconostoc spp. e Micrococcus spp. NSLAB termoduricas como Bacillus spp. também são relatadas. As NSLAB em queijos podem ajudar a desenvolver sabor e aroma, porém também são associadas aos defeitos em queijos e leites fermentados. Problemas como odores estranhos, sabor amargo ou muito ácido, perda de viscosidade, perda de coloração, estufamento e formação de gás são associados com a presença e contaminação por NSLAB. Assim, as BAL são importantes micro-organismos na indústria láctea, garantindo sabores e aromas aos derivados. Já a presença de NSLAB podem ser associados com defeitos em queijos e leites fermentados, sendo um problema na indústria beneficiadora.   Palavras-chave: Característica Sensorial. Leites Fermentados. Queijo. Textura.                       Abstract Fermented dairy products contain acid bacteria (BAL) naturally present or added to the dairy matrix as starter cultures (starters), contributing to aroma, texture, nutritional value and microbiological safety. Lactobacillus spp., Streptococcus spp., Lactococcus spp. and Leuconostoc spp. are used as starter dairy crops. As BAL it can be classified as mesophilic (ex: Lactococcus lactis) and thermophilic (ex: Streptococcus thermophilus), and agree with its fermentation metabolites in homofermentative (lactic acid) and heterofermentative (lactic acid, carbon dioxide, diacetyl and other flavorings). Among the BAL, there is a group of lactic bacteria that are not part of the dairy culture (non-initiating lactic acid bacteria - NSLAB) that originate from raw milk, the milking environment or the biofilm-forming industry. NSLAB is represented by heterofermentative species of mesophilic lactobacilli such as Lactobacillus casei spp., L. paracasei spp., L. rhamnosus spp. and L. plantarum spp., and also by Pediococcus spp., Leuconostoc spp. and Micrococcus spp. Termoduric NSLAB such as Bacillus spp. are also related. NSLAB in cheeses may help develop flavor and aroma, and they are also associated with defects in fermented cheeses and milks. Problems such as strange odors, bitter or very acidic taste, loss of viscosity, loss of color, establishment and gas training are associated with the presence and contamination by NSLAB. Thus,  BALs are important microorganisms in the dairy industry, contributing to the dairy flavors and aromas. The presence of NSLAB, on the other hand, can be associated with defects in fermented milk and cheese, being a problem in the processing industry.   Keywords: Cheese. Fermented Milk. Sensory Characteristic. Texture.

The survival of Pediococcus acidilactici (0110 TAT-1), Lactobacillus casei (NRRL-B 1922) and Listeria monocytogenes (ATCC 1194) on the Curing Types

2016 ◽  
Vol 6 (1) ◽  
pp. 34-38
Author(s):  
Happy Nursyam ◽  
Widjanarko S B ◽  
Sukoso Sukoso
Keyword(s):  
Lactic Acid ◽  
Listeria Monocytogenes ◽  
Lactobacillus Casei ◽  
Pathogenic Bacteria ◽  
Incubation Temperature ◽  
Starter Culture ◽  
Starter Cultures ◽  
Pediococcus Acidilactici ◽  
Fermented Sausage ◽  
Liquid Smoke

Lactic acid bacteria (LAB) consist of four genera, namely Lactobacillus, Leuco-nostoc, Pediococcus, and Streptococcus. Pediococcus and Lactobacillus are used as starter cultures in the processing of fermented food products such as sour milk, shrimp paste and fermented sausage. . The use of starter culture is intended to speed up the fermentation process as well as inhibiting the growth of other pathogenic bacteria. Common LAB are gram-positive, do not have spores, cocci or bacilli, and produce lactic acid from the fermenta-tion of carbohydrates. Antimicrobial components produced by LAB can inhibit the growth of pathogenic bacteria in fermented products, for example Pediocin produced by P. acidilactici and Lactasin by L. casei. Fermented meat products may possibly be contaminated by Listeria monocytogenes if the implementation is not hygienic. In fermented sausage processing, commonly used preservatives are: NaCl, NaNO2, NaNO3, liquid smoke, pH, and lactic acid. The purpose of this study was to determine the survival of Pediococcus acidilactici, Lactobacillus casei, and Listeria monocytogenes in some kind of curing with different concentrations. The method used is descriptive, where data are shown as mean ± STD. The results showed that P. acidilactici, L. ca-sei, and L.monocytogenes can survive at a rate of NaCl 0-3%; NaNO2 0-100 ppm; NaNO3 0-200 ppm; liquid smoke 0-4%; pH 3 - 5.6; and the incubation temperature of 5-50 °C.

Antibiotic Resistance of Lactobacilli Isolated from Two Italian Hard Cheeses

2009 ◽  
Vol 72 (10) ◽  
pp. 2162-2169 ◽  
Author(s):  
NICOLETTA BELLETTI ◽  
MONICA GATTI ◽  
BENEDETTA BOTTARI ◽  
ERASMO NEVIANI ◽  
GIULIA TABANELLI ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Starter Cultures ◽  
Lactobacillus Helveticus ◽  
Penicillin G ◽  
Significant Difference ◽  
Grana Padano ◽  
Parmigiano Reggiano

One hundred forty-one lactobacilli strains isolated from natural whey starter cultures and ripened Grana Padano and Parmigiano Reggiano cheeses were tested for their susceptibility to 13 antibiotics, in particular, penicillin G, ampicillin, amoxicillin, oxacillin, cephalotin, cefuroxime, vancomycin, gentamicin, tetracycline, erythromycin, clindamycin, co-trimoxazole, and nitrofurantoin. The strains belonged to the species Lactobacillus helveticus, L. delbrueckii subsp. lactis, L. rhamnosus, and L. casei. The strains of the first two species were isolated from whey starter cultures, and the strains of the last two species were from the ripened cheeses. Significant differences among the strains in their antibiotic resistance were found in relation to the type of cheese and, especially, the strains from Parmigiano Reggiano were more resistant to gentamicin and penicillin G. The strains isolated in the ripened cheese were generally more resistant than those isolated from natural whey starter cultures; in particular, significant differences regarding oxacillin, vancomycin, cephalotin, and co-trimoxazole were observed. Finally, no significant difference in relation to the type of cheese was found among the thermophilic lactobacilli isolated from whey cultures, while the facultatively heterofermentative lactobacilli isolated from Parmigiano Reggiano showed higher resistance toward gentamicin and penicillin G than did the same species isolated from Grana Padano.

Transformation kinetics of fermented milk using Lactobacillus casei (Lc1) and Streptococcus thermophilus: comparison of results with other Inocula

2016 ◽  
Vol 84 (1) ◽  
pp. 102-108
Author(s):  
Susana Vargas Muñoz ◽  
Francisco Quintanilla Guerrero ◽  
Maykel González Torres ◽  
Ma del Pilar Carreón Castro ◽  
Rogelio Rodríguez Talavera
Keyword(s):  
Lactic Acid ◽  
Lactobacillus Casei ◽  
Streptococcus Thermophilus ◽  
Fermented Milk ◽  
Starter Cultures ◽  
Lactobacillus Delbrueckii ◽  
Transformation Kinetics ◽  
Lactobacillus Johnsonii ◽  
Kinetics Of ◽  
Improved Characteristics

Probiotic-based starter cultures are generally used to produce fermented milks with improved characteristics in the final product. In this study, Lactobacillus casei and Streptococcus thermophilus (Lc1-St) were used as the starter inoculum. The transformation kinetics and properties of the final product were compared with systems produced with other inocula. The Lc1-St inoculum delayed the production of lactic acid from 40 to 70 min (depending on temperature and concentration) when compared to Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus (Lb-St) and Lactobacillus johnsonii and Streptococcus thermophilus (La1-St). The Lc1-St inoculum reached the aggregation system faster (30–80 min) than Lb-St (120–210 min) and La1-St (160–220 min), however, the production of exopolysaccharides and organic phosphates was delayed as a consequence of the lack of synergy between Lc1 and St.

scholarly journals In Silico Prediction of Horizontal Gene Transfer Events in Lactobacillus bulgaricus and Streptococcus thermophilus Reveals Protocooperation in Yogurt Manufacturing

2009 ◽  
Vol 75 (12) ◽  
pp. 4120-4129 ◽  
Author(s):  
Mengjin Liu ◽  
Roland J. Siezen ◽  
Arjen Nauta
Keyword(s):  
Gene Transfer ◽  
Horizontal Gene Transfer ◽  
Gene Cluster ◽  
In Silico ◽  
Bacterial Species ◽  
Streptococcus Thermophilus ◽  
Starter Cultures ◽  
Lactobacillus Helveticus ◽  
Lactobacillus Bulgaricus ◽  
Genetic Level

ABSTRACT Lactobacillus bulgaricus and Streptococcus thermophilus, used in yogurt starter cultures, are well known for their stability and protocooperation during their coexistence in milk. In this study, we show that a close interaction between the two species also takes place at the genetic level. We performed an in silico analysis, combining gene composition and gene transfer mechanism-associated features, and predicted horizontally transferred genes in both L. bulgaricus and S. thermophilus. Putative horizontal gene transfer (HGT) events that have occurred between the two bacterial species include the transfer of exopolysaccharide (EPS) biosynthesis genes, transferred from S. thermophilus to L. bulgaricus, and the gene cluster cbs-cblB(cglB)-cysE for the metabolism of sulfur-containing amino acids, transferred from L. bulgaricus or Lactobacillus helveticus to S. thermophilus. The HGT event for the cbs-cblB(cglB)-cysE gene cluster was analyzed in detail, with respect to both evolutionary and functional aspects. It can be concluded that during the coexistence of both yogurt starter species in a milk environment, agonistic coevolution at the genetic level has probably been involved in the optimization of their combined growth and interactions.

Lactic Acid Production by Streptococcus thermophilus and Lactobacillus bulgaricus in Milk Precultured with Psychrotrophic Bacteria

1977 ◽  
Vol 40 (7) ◽  
pp. 475-479 ◽  
Author(s):  
M. A. COUSIN ◽  
E. B. MARTH
Keyword(s):  
Lactic Acid ◽  
Acid Production ◽  
Lactic Acid Production ◽  
Titratable Acidity ◽  
Streptococcus Thermophilus ◽  
Raw Milk ◽  
Starter Cultures ◽  
Lactobacillus Bulgaricus ◽  
Psychrotrophic Bacteria ◽  
Cell Free Filtrate

Raw milk was incubated at 7 C for 5 days after it was inoculated with psychrotophic bacteria previously isolated from other raw milks. Then a portion of each sample of milk was pasteurized; the remainder was autoclaved. Streptococcus thermophilus and Lactobacillus bulgaricus were individually inoculated into all pasteurized and autoclaved milks which were then incubated at 37 C and titratable acidity was measured at 2-h intervals. Pasteurized milks precultured with psychrotrophic bacteria supported more acid production than did pasteurized control milks. S. thermophilus and especially L. bulgaricus produced more acid in autoclaved than in pasteurized milks. Cell-free filtrates from cultures of psychrotrophic bacteria were added to raw, pasteurized, and autoclaved milks before they were inoculated with the lactic acid bacteria. Results were similar to those obtained when psychrotrophic bacteria were added to milk. When the cell-free filtrate was added to milks simultaneously with starter cultures, less than 10 h were required to produce conditions in milk favorable for enhanced lactic acid production.

Effects of different starter cultures on the ripening characteristics of Golot cheese

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Hayriye Sekban ◽  
Zekai Tarakci
Keyword(s):  
Positive Impact ◽  
Starter Culture ◽  
Control Sample ◽  
Streptococcus Thermophilus ◽  
Sensory Properties ◽  
Starter Cultures ◽  
Lactobacillus Helveticus ◽  
Lactobacillus Bulgaricus ◽  
Content Type ◽  
Positive Effects

Purpose The purpose of this study was to investigate the chemical, textural and sensory properties of some starter cultures fruit-added Golot cheese. Design/methodology/approach Six types of Golot cheeses were produced in this study. While the control sample contained no starter cultures, five different starter culture combinations (GS1: Streptococcus thermophilus, Lactococcus lactis subsp. cremoris, L. lactis subsp. lactis and Lactobacillus bulgaricus; GS2: S. thermophilus and L. bulgaricus; GS3: S. thermophilus; GS4: S. thermophilus and Lactobacillus helveticus; and GS5: S. thermophilus, L. lactis subsp. cremoris and L. lactis subsp. lactis) were applied to the other cheese samples using an immersion technique. Then, all cheeses were vacuum-packed and ripened at 4 ± 1°C for three months and their chemical, biochemical, sensory and textural analyses were performed on the 2nd, 15th, 30th, 60th and 90th days of ripening. Findings Results indicated that generally starter cultures have positive effects on the chemical, biochemical and sensory properties of Golot cheese. Considering the final values, the addition of starter cultures enhanced the ripening index of Golot cheeses (8.4%–9.2%), except the GS3 (7.4%), compared to the control (8.1%). At the end of the ripening period, meltability values of GS4 (16.5 mm) cultured cheeses were higher than those of other cultured cheeses (13.0–15.5 mm) and control cheese (14.5 mm). While lipolysis values were low in fresh cheese, it increased during ripening. Overall, GS3 (2.46 acid degree value [ADV]) and GS4 (2.40 ADV) had the highest lipolysis rate, while GS1 (2.14 ADV) had the lowest (p = 0.07). Electrophoretograms indicated that the highest fragmentation of α- and ß-casein occurred in GS5 (48.43%) and GS1 (44.24%), respectively. Also, GS5 was the most appreciated and preferred cheese in terms of sensory. Regarding texture, hardness, cohesiveness, adhesiveness, springiness and gumminess values were determined to be statistically important in terms of ripening time and cheese variety (p < 0.01). Originality/value Consequently, all starters had a positive impact on Golot cheese samples and among all S. thermophilus and L. helveticus starter were determined to be the most applicable one considering ripening, texture, sensory and melting properties.

scholarly journals Selection and study on technological parameters of symbiotic starter cultures Lactobacillus bulgaricus and Streptococcus thermophilus for production of Vietnamese yogurt

2020 ◽  
Vol 3 (2) ◽  
pp. 118
Author(s):  
Thanh Le ◽  
Bogdan Goranov ◽  
Radka Vlaseva
Keyword(s):  
Maximum Rate ◽  
Starter Culture ◽  
Titratable Acidity ◽  
Streptococcus Thermophilus ◽  
Starter Cultures ◽  
Lactobacillus Bulgaricus ◽  
Technological Parameters ◽  
Coagulation Time ◽  
The Moment ◽  
Natural Milk

In this paper ten symbiotic starter cultures for yogurt production were examined for their coagulation time, titratable acidity, pH at the moment of coagulation. Their maximum rate of acidification was also determined by model of fermentation kinetics. Three starter cultures were selected for production of Vietnamese yogurt. With the selected starter culture, yogurt from natural milk and reconstituted whole milk was obtained. Their coagulation time, acidity, maximum rate of acidification and rate of acidification during storage of product were studied. As a result of this study and mathematical modeling, we concluded that maximum rate of acidification at moment of coagulation and during storage was affected by the type of milk used in yogurt production.

Sign in / Sign up

Export Citation Format

Share Document