Statistical modelling for optimized lyophilization of Lactobacillus acidophilus strains for improved viability and stability using response surface methodology (original) (raw)
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Optimization of the Viability of Probiotics in a Fermented Milk Drink by the Response Surface Method
Asian-Australasian Journal of Animal Sciences, 2004
Preparation of fermented milk drinks The milk used in the experiments was reconstituted from high heat treated whole milk powder (12% total solids, Anchor, New Zealand), heat treated at 85°C for 30 min. A series of pretests were conducted and the results indicated that milk inoculated with 1% of L. acidophilus and 2% of B.longum and fermented for 10 h would produce the highest viability of probiotic cultures. Therefore, experimental samples were prepared using skim milk inoculated with 1% of L. acidophilus and 2% of B. longum. After fermentation for 10 h at 37°C (final pH about 5.75), the samples were then mixed with vegetable juice (V8 100% Vegetable Juice, Campbell Soup Company, NJ, USA) in the ratio of 1:1 to produce a new fermented milk drink (final pH about 5.4).
International Dairy Journal, 2003
The simultaneous effect of fermentation temperature (FT,, milk total solid level (TS,.7%, w/v) and total inoculum concentration (TI, 2.16-3.84 v/v) on the acidification process and the rheological properties of fermented milk products with Lactobacillus paracasei ssp paracasei B117, Lactobacillus delbrueckii ssp bulgaricus Y 6.15 and Streptococcus thermophilus Y 4.10 was explored by means of response surface methodology. Maximum storage modulus (G 0 max ), minimum loss tangent (tan d min ), rate of gelation (I E ) and onset of gelation were the rheological parameters studied. Maximum acidification rate (V m ), time at which maximum acidification rate was observed (T m ), and time to reach the end of fermentation (T e ) characterized the kinetics of acidification, whereas the increase in the number of the three bacteria at the end of fermentation was chosen as the microbiological parameter of the system. The growth/survival of microorganisms and the organic acid profile during cold storage as well as the overall product acceptability by a consumer panel were also assessed. TS strongly affected G 0 max and tan d min ; high TS resulted in large increase in G 0 max and decrease in tan d min : Increasing fermentation temperature gave a decrease in the onset of gelation, V m ; T m and T e ; and an increase in the gelation rate (I E ). Under conditions of relatively low FT (37-40 C), high TS (about 14%) and high TI (3-4%), relatively high gelation and low acidification rates were observed, fermentation took a longer time to finish, but the formed gels were firmer, showing higher G 0 max and lower tan d min values. Low FT (36-38 C) enabled higher increase in the number of L. paracasei B 117. The probiotic strain showed good compatibility with the S. thermophilus Y 4.10 and L. bulgaricus Y 6.15, and satisfactory levels of all bacteria were found during fermentation and storage at 4 C for 21 days. No major differences in lactic and uric acid contents were seen between the control (probiotic strain-free product) and the probiotic fermented milk, whereas the latter contained slightly higher amounts of citric, pyruvic and orotic acids. Moreover, the probiotic fermented milk was graded by the consumer panel with a similar acceptability score as the control product. r
Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Agriculture, 2012
For a very long time, probiotics have been selected on the basis of their suitability to food's environment and technological procedures, as well as survival ability in vitro and also in vivo. These criteria are still used. The aim of this study was to select, using the Plakett-Burman design of experiments model, of three significant factors, which influence the multiplication ability and viability of probiotic strains Lactobacillus acidophilus (commercial code LA-5 ®) and Lactobacillus casei subsp. paracasei (commercial code L. casei 431 ®) in fermented mesophilic milk product (commercial named Sana) obtained by fermentation with a multiple culture with mesophilic lactic starter Flora Danica Chr. Hansen commercial starters (Lactococcus lactis subsp. cremoris, Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. diacetylactis and Leuconostoc mesenteroides subsp. cremoris). By statistical analysis the most important factors (independent variables) with influence on the probiotic bacteria were selected for the optimized. These are the temperature of fermentation; the ratio between probiotic strains and Flora Danica and the addition of prebiotic Fagopyrum esculentum flour. In the future experiments the optimum values of these parameters will be optimized by using response surface methodology, in order to establish the conditions in which can be obtain the mesophilic fermented milk products with probiotic action in vivo.
Food Science and Technology
The incorporation of probiotics into fermented milk is beneficial for the consumer's health and it is important to know the viability of these microorganisms in the product, from production to final consumption. This research carried out a predictive study on the behavior of Lactobacillus acidophilus LAFTI L10 probiotic strain during the fermentation and storage stages of whole goat milk yogurt. Selective counts of L. acidophilus were performed with MRS medium added with clindamycin. The primary model of nonlinear regression by Baranyi and Roberts was fit to the experimental data in DMFit 3.5 software and statistically evaluated. The total fermentation time of the yogurt was 6.5 h and 3 logarithmic cycles of probiotic cell growth were observed. During storage, time influenced the concentration of L. acidophilus from the 30th day onwards, maintaining a minimum count that allows the denomination of probiotic yogurt to the product and certifying its quality. The Baranyi and Roberts model fit satisfactorily the experimental data. The results can benefit the dairy industry in the development, optimization, and reliability of their processes for dairy products.
According to the currently adopted definition by Food and Agriculture Organization and World Health Organization, the probiotics represent live microorganisms, which when administered in adequate amounts confer a health benefit on the host. In this respect, probiotic bacteria are increasingly used in food and pharmaceutical applications to balance disturbed intestinal microflora and related dysfunction of the human gastrointestinal tract. However, due to the short lifespan of probiotics, efforts are targeted to the evaluation of the contribution of the prebiotics in the improvement of the viability of those microorganisms. Their importance resides in the fact that, as food ingredients, the y stimulate selectively the growth and activity of bifidobacteria and lactobacilli in the gut and thereby benefit health. It is generally accepted that in the case of functional food, the minimum number of live probiotic microflora should range from 10 5 to 10 6 cfu/mL or gram of product. More, it was demonstrated that, in order to achieve evident health results, it is necessary to consume at least approximately 10 8 to 10 9 of live microbial cells daily in fermented milk.This paper comes to present the analysis made on the survival of two pure freeze dried cultures Lb. acidophilus and Bifidobacterium animalis subsp. lactis BB 12 (Chr. Hansen, Romania) during the lactic acid fermentation of some vegetable juices. The number of the bacteria population was determined by plate count method using Man-Rogosa-Sharpe agar, enriched with cysteine, and data related to the concentration of viable probiotic bacteria, as time function, were registered. Like results, regression models were determined for emphasizing the shape of bacteria concentration curve. For this purpose, Microsoft Excel and CurveExpert software applications were used, for proceeding graphing examination of the curve fit, but also for determining the best fit when comparing the data to each model.
Acta Scientiarum. Health Sciences
Lactobacillus acidophilus used in three different applications, compounding pharmacies (LA1), fermented dairy (LA2), and allopathic compoundings (LA3) were tested to evaluate the existence of significant differences between them and in different growth conditions. In the evaluation of resistance to different commercial use antibiotics, all strains were sensitive to the antibiotics ampicillin, chloramphenicol, doxycycline, and tetracycline. LA1 was considered moderately sensitive (MS) to erythromycin and LA3 was MS to clindamycin and erythromycin. LA3 was classified between MS to resistant to erythromycin. All three strains were resistant to gentamicin. When evaluating acid pH resistance, the three origins presented similar behavior, with a decrease in cell viability at pH 2, maintaining constant viability at pH 3 and 4. In the test of resistance to the gastrointestinal tract conditions and hydrophobicity, LA2 presented better results. The three strains showed production of inhibito...
Journal of Biotechnology, 2012
Probiotics are administered as complex manufactured products and yet most studies on probiotic bacterial strains have been performed with native culture strains. Little is known about the influence of industrial processes on the properties of the microorganisms. In this study, we comparatively assessed the characteristics of the probiotic bacterial strain Lactobacillus rhamnosus (Lcr35 ® ) together with four of its commercial formulations, including three intestinal formulas (BACILOR with Lcr Restituo ® packet and capsule and FLOREA Lcr Lenio ® ) and one vaginal formula (GYNOPHILUS Lcr Regenerans ® ). Lcr35 ® grown from the intestinal formulas displayed increased resistance to acidic pH and bile stress, especially FLOREA (Lcr Lenio ® ), which showed a 4.5 log higher number of viable bacteria compared to the results obtained with the control native Lcr35 ® strain. Adhesion to intestinal cells was significantly higher with Lcr Restituo ® packet and Lcr Restituo ® capsule vs Lcr35 ® . Bacteria from the vaginal formulation GYNOPHILUS had increased ability to metabolize glycogen thereby increasing lactic acid production. In vitro growth inhibition of the pathogen Candida albicans was significantly higher with bacteria from the vaginal formulation (4.5 log difference) and in the presence of vaginal epithelial cells than with the native strain. Our results show that the manufacturing process influences strain properties and should therefore be adapted according to the strain and the therapeutic indication.
Foods, 2020
It is well known that intake of probiotic brings health benefits. Lactic bacteria with probiotic potential have aroused the interest of the industry in developing food products that incorporate such benefits. However, incorporating probiotic bacteria into food is a challenge for the industry, given the sensitivity of probiotic cultures to process conditions. Therefore, the objective of this study is to evaluate gelatin- and inulin-based filmogenic solutions as a potential vehicle for incorporating probiotics into food products and to model the fermentation kinetics. L. salivarius (Lactobacillus salivarius) growth in filmogenic solutions was analyzed under the influence of a variety gelatin concentrations (1.0–3.0%) and inulin concentrations (4.0–6.0%) and fermented under the effect of different temperatures (25–45 °C). A full 23 factorial plan with three replicates at the central point was used to optimize the process. The impacts of process conditions on cell development are fundam...
Bacteria Empire, 2019
Currently, the food industry wants to expand the range of probiotic yogurts but each probiotic bacteria offers different and specific health benefits. This study examined the viable counts of Lactobacillus acidophilus and percentage syneresis of probiotic yoghurt produced from reconstituted skim and whole milk powder stored for 35 days at 4±2 o C. Skim milk probiotic yoghurt (SMPY) and Whole milk probiotic yoghurt (WMPY) were produced by reconstituting dry milk powder (130 g/900 ml w/v), which was pasteurized at 85 o C for 15 mins, cooled to 43 o C and inoculated with freeze dried probiotic yoghurt mixed starter culture containing Streptococcus thermophilus (ST), Lactobacillus bulgaricus (LB) and Lactobacillus acidophilus (LA). The yoghurt samples were analyzed for viability of ST, LB, LA and also syneresis. During storage, the viable counts of ST in SMPY decreased from 5.43x10 8 to 5.18x10 6 cfu/ml, LB (2.47x10 8 to 8.10x10 5 cfu/ml) and LA (1.83x10 8 to 5.78x10 5 cfu/ml). Similarly, the viable counts of ST in WMPY decreased significantly from 5.40x10 8 to 5.15x10 6 cfu/ml, LB (2.43x10 8 to 7.82x10 5 cfu/ml) and LA (1.80x10 8 to 5.84x10 5 cfu/ml). Although the mean viable counts of the LA decreased during storage, both SMPY and WMPY still contained an average of 1.48x10 6 cfu/ml of probiotic cells up to 28 days of storage, which is above the "therapeutic minimum" of 10 6 cfu/ml. The percentage syneresis of SMPY and WMPY increased significantly during the 35 days of storage, from 24.4-32.0 % and 24.8-32.7 % respectively. There was a positive correlation between storage time and syneresis thus affecting the texture. In conclusion, yoghurt made from either skim or whole milk powder can be used as an adequate carrier of LA (probiotic bacteria) up to a period of 28 days at 4±2 o C and a stabilizer should be used to reduce the separation of whey and thus maintain the texture.
Journal of Food Science, 2003
Calcium gluconate (0.0 to 0.5%), sodium gluconate (0.0 to 1.0%), and N-acetylglucosamine (0.0 to 1.0%) were added to skim milk to retain the viability of Lactobacillus acidophilus and Bifidobacterium longum. To carry out response surface modeling, the regression method was performed on experimental results to build mathematical models. The models were then formulated as an objective function in an optimization problem that was consequently optimized using a genetic algorithm approach to obtain the maximum viability of the probiotics. The genetic algorithms (GAs) were examined to search for the optimal value. The results indicated that GAs were very effective for optimizing the activity of probiotic cultures.