scholarly journals Effects of Different Stress Parameters on Growth and on Oleuropein-Degrading Abilities of Lactiplantibacillus plantarum Strains Selected as Tailored Starter Cultures for Naturally Table Olives

2020 ◽  
Vol 8 (10) ◽  
pp. 1607
Author(s):  
Amanda Vaccalluzzo ◽  
Alessandra Pino ◽  
Maria De Angelis ◽  
Joaquín Bautista-Gallego ◽  
Flora Valeria Romeo ◽  
...  
Keyword(s):  
Salt Content ◽  
Maximum Growth ◽  
Maximum Growth Rate ◽  
Starter Cultures ◽  
Stress Factors ◽  
Process Conditions ◽  
Table Olives ◽  
Low Salt ◽  
Beta Glucosidase ◽  
Selection Of

The use of β-glucosidase positive strains, as tailored-starter cultures for table olives fermentation, is a useful biotechnological tool applied to accelerate the debittering process. Nowadays, strains belonging to Lactiplantibacillus plantarum species are selected for their high versatility and tolerance to stress conditions. The present study investigated the effect of different stress factors (pH, temperature and NaCl) on growth and on oleuropein-degrading abilities of selected L. plantarum strains. In addition, the presence of the beta-glucosidase gene was investigated by applying a PCR based approach. Results revealed that, overall, the performances of the tested strains appeared to be robust toward the different stressors. However, the temperature of 16 °C significantly affected the growth performance of the strains both singularly and in combination with other stressing factors since it prolongs the latency phase and reduces the maximum growth rate of strains. Similarly, the oleuropein degradation was mainly affected by the low temperature, especially in presence of low salt content. Despite all strains displayed the ability to reduce the oleuropein content, the beta-glucosidase gene was detected in five out of the nine selected strains, demonstrating that the ability to hydrolyze the oleuropein is not closely related to the presence of beta-glucosidase. Data of the present study suggest that is extremely important to test the technological performances of strains at process conditions in order to achieve a good selection of tailored starter cultures for table olives.

The effect of low sludge age on wastewater fractionation (SS, SI)

2003 ◽  
Vol 47 (11) ◽  
pp. 203-209 ◽  
Author(s):  
S. Haider ◽  
K. Svardal ◽  
P.A. Vanrolleghem ◽  
H. Kroiss
Keyword(s):  
Activated Sludge ◽  
Maximum Growth ◽  
Maximum Growth Rate ◽  
The Other ◽  
Second Stage ◽  
Lower Maximum ◽  
The Difference ◽  
Selection Of ◽  
Activated Sludge Systems ◽  
Raw Wastewater

In lab-scale experiments at the 2-stage activated sludge pilot plant of Vienna's central WWTP it is shown that the wastewater soluble COD concentration, which is inert to a sludge with SRT < 1 d (SIA) is about double compared to the SI concentration in sludge with SRT > 10 d (SIB). Unexpectedly the ratio of SIA/SIB is independent of the sludge age between SRTs of 0.4 and 1.0 days. The difference between the two SI fractions is soluble COD that is readily biodegradable by the sludge with SRT > 10 d. However, it is degraded at a lower maximum growth rate. These results comply with earlier results gained with different methods and at different WWTPs. It is hypothesised that very low sludge ages result in a selection of fast growing bacteria, which can utilise only part of the SS in the raw wastewater. The other part of SS therefore remains in the wastewater and can thus be utilised for enhanced denitrification in the second stage. It is still unknown beyond which sludge age the soluble inert COD SIA starts to decrease, finally reaching the value SIB for low loaded systems (SRT > 5 days). From this point on SI and SS are assumed only to depend on the wastewater composition and not on the sludge age. The assumption of the Activated Sludge Model No.1 that the biodegradable fractions can be modelled as a single substrate and by a single removal kinetic (one Monod term) appears not to be applicable for low sludge ages. Some suggestions for mathematical modelling, design and operation of 2-stage activated sludge systems are given.

scholarly journals Effect of Sequential Inoculum of Beta-Glucosidase Positive and Probiotic Strains on Brine Fermentation to Obtain Low Salt Sicilian Table Olives

2019 ◽  
Vol 10 ◽  
Author(s):  
Alessandra Pino ◽  
Amanda Vaccalluzzo ◽  
Lisa Solieri ◽  
Flora V. Romeo ◽  
Aldo Todaro ◽  
...  
Keyword(s):  
Table Olives ◽  
Low Salt ◽  
Probiotic Strains ◽  
Beta Glucosidase

scholarly journals Selection of Yeasts as Starter Cultures for Table Olives: A Step-by-Step Procedure

2012 ◽  
Vol 3 ◽  
Author(s):  
Antonio Bevilacqua ◽  
Maria Rosaria Corbo ◽  
Milena Sinigaglia
Keyword(s):  
Starter Cultures ◽  
Table Olives ◽  
Step Procedure ◽  
Selection Of

scholarly journals The Use of Starter Cultures in Traditional Meat Products

2017 ◽  
Vol 2017 ◽  
pp. 1-18 ◽  
Author(s):  
Marta Laranjo ◽  
Miguel Elias ◽  
Maria João Fraqueza
Keyword(s):  
Starter Culture ◽  
Meat Products ◽  
Starter Cultures ◽  
Rapid Screening ◽  
Process Conditions ◽  
Safety Improvement ◽  
Cured Meat ◽  
Wild Strains ◽  
Bacteria And Fungi ◽  
Selection Of

Starter cultures could play an essential role in the manufacture of traditional cured meat products. In order to achieve objectives related to meat products’ quality and safety improvement, the selection of particular strains constituting a starter culture should be carried out in the context of its application, since its functionality will depend on the type of sausage and process conditions. Also, strain selection should comply with particular requirements to warrant safety. The aim of the current review is to update the knowledge on the use of starter cultures in traditional meat products, with focus on dry-fermented products. In this manuscript, we will try to give answers to some relevant questions: Which starter cultures are used and why? Why are LAB used? What are their role and their specific mode of action? Which other groups of microorganisms (bacteria and fungi) are used as starter cultures and how do they act? A particular revision of omics approach regarding starter cultures is made since the use of these techniques allows rapid screening of promising wild strains with desirable functional characteristics, enabling the development of starter cultures better adapted to the meat matrix.

scholarly journals Development and Application of a Bioluminescence-Based Test for Assimilable Organic Carbon in Reclaimed Waters

2009 ◽  
Vol 75 (23) ◽  
pp. 7385-7390 ◽  
Author(s):  
Lauren A. Weinrich ◽  
Eugenio Giraldo ◽  
Mark W. LeChevallier
Keyword(s):  
Drinking Water ◽  
Organic Carbon ◽  
Heterotrophic Bacteria ◽  
Maximum Growth ◽  
Maximum Growth Rate ◽  
Treatment Practices ◽  
Watershed Protection ◽  
Assimilable Organic Carbon ◽  
Maximum Cell ◽  
Selection Of

ABSTRACT Assimilable organic carbon (AOC) is an important parameter governing the growth of heterotrophic bacteria in drinking water. Despite the recognition that variations in treatment practices (e.g., disinfection, coagulation, selection of filter media, and watershed protection) can have dramatic impacts on AOC levels in drinking water, few water utilities routinely measure AOC levels because of the difficulty of the method. To simplify the method, the Pseudomonas fluorescens P-17 and Spirillum sp. strain NOX test bacteria were mutagenized by using luxCDABE operon fusion and inducible transposons to produce bioluminescent strains. The growth of these strains can easily be monitored with a programmable luminometer to determine the maximum cell yield via luminescence readings, and these values can be fitted to the classical Monod growth curve to determine bacterial growth kinetics and the maximum growth rate. Standard curves using acetate carbon (at concentrations ranging from 0 to 1,000 μg/liter) resulted in coefficients of determination (r 2) between luminescence units and acetate carbon levels of 0.95 for P-17 and 0.89 for NOX. The bioluminescence test was used to monitor reclaimed water, in which average AOC levels range between 150 and 1,400 μg/liter acetate carbon equivalents. Comparison of the conventional AOC assay and the bioluminescent assay produced an r 2 of 0.92.

Predicting the growth of Listeria monocytogenes in cooked sliced deli turkey breast as function of clean label antimicrobial, pH, moisture and salt

2021 ◽  
Author(s):  
SUBASH SHRESTHA ◽  
Jerry Joseph Erdmann ◽  
Sean A Smith
Keyword(s):  
Growth Rate ◽  
Listeria Monocytogenes ◽  
Control Measure ◽  
Salt Content ◽  
Maximum Growth ◽  
Lag Time ◽  
Maximum Growth Rate ◽  
Lag Phase ◽  
Design Matrix ◽  
Least Squares Regression

The use of antimicrobials in formulations of ready-to-eat meat and poultry products has been identified as a major strategy to control Listeria monocytogenes . The USDA-FSIS recommends no more than 2-logs of Listeria outgrowth over the stated shelf life if antimicrobials are used as a control measure for a product with post-lethality environmental exposure. This study was designed to understand the efficacy of a clean label antimicrobial against the growth of L. monocytogenes as affected by the product attributes. A response surface method-central composite design was used to investigate the effects of product pH, moisture, salt content, and a commercial “clean-label” antimicrobial on the growth of L. monocytogenes in a model turkey deli meat formulation. Thirty treatment combinations of pH (6.3, 6.5, and 6.7), moisture (72, 75, and 78%), salt (1.0, 1.5, and 2.0%), and antimicrobial (0.75, 1.375, and 2.0%) with six replicated center points and eight design star points were evaluated. Treatments were surface inoculated with a 3 log 10 CFU/g target of a five-strain L. monocytogenes cocktail, vacuum packaged, and stored at 5°C for up to 16 weeks. Populations of L. monocytogenes were enumerated from triplicate samples every week until the stationary growth phase was reached. The enumeration data was fitted to a Baranyi and Roberts growth curve to calculate the lag time and maximum growth rate for each treatment.  Linear least-squares regression of the lag-time and growth-rate against the full quadratic, including the second order interaction terms, design matrix was performed. Both lag time and maximum growth rate were significantly affected ( p <0.01) by the antimicrobial concentration and product pH. Product moisture and salt content affected ( p <0.05) lag phase and maximum growth rate, respectively. The availability of a validated growth model assists meat scientists and processors with faster product development and commercialization.

Selection of Yeasts as Starter Cultures for Table Olives

2013 ◽  
Vol 78 (5) ◽  
pp. M742-M751 ◽  
Author(s):  
Antonio Bevilacqua ◽  
Luciano Beneduce ◽  
Milena Sinigaglia ◽  
Maria Rosaria Corbo
Keyword(s):  
Starter Cultures ◽  
Table Olives ◽  
Selection Of

Characterization of Lactic Acid Bacteria Isolated from Italian Bella di Cerignola Table Olives: Selection of Potential Multifunctional Starter Cultures

2010 ◽  
Vol 75 (8) ◽  
pp. M536-M544 ◽  
Author(s):  
Antonio Bevilacqua ◽  
Clelia Altieri ◽  
Maria Rosaria Corbo ◽  
Milena Sinigaglia ◽  
Labia Irène Ivette Ouoba
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Starter Cultures ◽  
Table Olives ◽  
Selection Of

scholarly journals Fermentation of Nocellara Etnea Table Olives by Functional Starter Cultures at Different Low Salt Concentrations

2018 ◽  
Vol 9 ◽  
Author(s):  
Alessandra Pino ◽  
Maria De Angelis ◽  
Aldo Todaro ◽  
Koenraad Van Hoorde ◽  
Cinzia L. Randazzo ◽  
...  
Keyword(s):  
Starter Cultures ◽  
Table Olives ◽  
Low Salt

Study on the Chemical Modification Process of Jute Fiber

TAPPI Journal ◽  
2010 ◽  
Vol 9 (2) ◽  
pp. 23-29 ◽  
Author(s):  
Wei-ming Wang ◽  
Zai-sheng Cai ◽  
Jian-yong Yu
Keyword(s):  
Sodium Hydroxide ◽  
Sodium Silicate ◽  
Treatment Time ◽  
Jute Fiber ◽  
Process Conditions ◽  
Silicate Concentration ◽  
Sodium Hydroxide Concentration ◽  
Liquor Ratio ◽  
Degumming Process ◽  
Selection Of

Degumming of pre-chlorite treated jute fiber was studied in this paper. The effects of sodium hydroxide concentration, treatment time, temperature, sodium silicate concentration, fiber-to-liquor ratio, penetrating agent TF-107B concentration, and degumming agent TF-125A concentration were the process conditions examined. With respect to gum decomposition, fineness and mechanical properties, sodium hydroxide concentration, sodium silicate concentration, and treatment time were found to be the most important parameters. An orthogonal L9(34) experiment designed to optimize the conditions for degumming resulted in the selection of the following procedure: sodium hydroxide of 12g/L, sodium silicate of 3g/L, TF-107B of 2g/L, TF-125A of 2g/L, treatment time of 105 min, temperature of 100°C and fiber to liquor ratio of 1:20. The effect of the above degumming process on the removal of impurities was also examined and the results showed that degumming was an effective method for removing impurities, especially hemicellulose.

Sign in / Sign up

Export Citation Format

Share Document