Use of central composite design in food microbiology: a case study on the effects of secondary phenols on lactic acid bacteria from olives

SYNOPSIS Response surface methodology (RSM), central composite design (CCD), and desirability functions were used for modelling and optimization of the operating factors in chlorite and talc (collectively termed 'mica') flotation. The influence of pulp pH, cyanide (NaCN) consumption, and particle size was studied with the aim of optimizing ssilicate flotation while minimizing recoveries of galena, chalcopyrite, and sphalerite. Flotation tests were carried out on a representative sample of a complex sulphide ore from Draa Sfar mine (Morocco). The model predictions for the flotation of each of the minerals concerned were found to be in good agreement with experimental values, with R2 values of 0.91, 0.98, 0.99, and 0.90 for mica, galena, chalcopyrite, and sphalerite recoveries, respectively. RSM combined with desirability functions and CCD was successfully applied for the modelling of mica flotation, considering simultaneously the four flotation responses to achieve the maximum recovery of mica and minimal loss of Pb, Cu, and Zn to the flotation concentrate. Keywords: chlorite, talc, flotation, response surface methodology, central composite design, optimization.

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Interactions between suspension characteristics and physicochemical properties of silver and copper oxide nanoparticles: A case study for optimizing nanoparticle stock suspensions using a central composite design

Chemosphere ◽

10.1016/j.chemosphere.2014.12.005 ◽

2015 ◽

Vol 124 ◽

pp. 136-142 ◽

Cited By ~ 8

Author(s):

Jino Son ◽

Janna Vavra ◽

Yusong Li ◽

Megan Seymour ◽

Valery Forbes

Keyword(s):

Physicochemical Properties ◽

Copper Oxide ◽

Central Composite Design ◽

Copper Oxide Nanoparticles ◽

Oxide Nanoparticles ◽

Central Composite

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Quantifying Nonthermal Inactivation of Listeria monocytogenes in European Fermented Sausages Using Bacteriocinogenic Lactic Acid Bacteria or Their Bacteriocins: A Case Study for Risk Assessment

Journal of Food Protection ◽

10.4315/0362-028x-69.11.2648 ◽

2006 ◽

Vol 69 (11) ◽

pp. 2648-2663 ◽

Cited By ~ 36

Author(s):

ELEFTHERIOS H. DROSINOS ◽

MARIOS MATARAGAS ◽

SLAVICA VESKOVIĆ-MORAČANIN ◽

JUDIT GASPARIK-REICHARDT ◽

MIRZA HADŽIOSMANOVIĆ ◽

...

Keyword(s):

Risk Assessment ◽

Lactic Acid ◽

Listeria Monocytogenes ◽

Lactic Acid Bacteria ◽

Storage Temperature ◽

Inactivation Kinetics ◽

Initial Population ◽

Log Reduction ◽

Fermented Sausages

Listeria monocytogenes NCTC10527 was examined with respect to its nonthermal inactivation kinetics in fermented sausages from four European countries: Serbia-Montenegro, Hungary, Croatia, and Bosnia-Herzegovina. The goal was to quantify the effect of fermentation and ripening conditions on L. monocytogenes with the simultaneous presence or absence of bacteriocin-producing lactic acid bacteria (i.e., Lactobacillus sakei). Different models were used to fit the experimental data and to calculate the kinetic parameters. The best model was chosen based on statistical comparisons. The Baranyi model was selected because it fitted the data better in most (73%) of the cases. The results from the challenge experiments and the subsequent statistical analysis indicated that relative to the control condition the addition of L. sakei strains reduced the time required for a 4-log reduction of L. monocytogenes (t4D). In contrast, the addition of the bacteriocins mesenterocin Y and sakacin P decreased the t4D values for only the Serbian product. A case study for risk assessment also was conducted. The data of initial population and t4D collected from all countries were described by a single distribution function. Storage temperature, packaging method, pH, and water activity of the final products were used to calculate the inactivation of L. monocytogenes that might occur during storage of the final product (U.S. Department of Agriculture Pathogen Modeling Program version 7.0). Simulation results indicated that the addition of L. sakei strains significantly decreased the simulated L. monocytogenes concentration of ready-to-eat fermented sausages at the time of consumption.

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Medium Optimization for Antimicrobial Production By Newly Screened Lactic Acid Bacteria

ANNALES BOGORIENSES ◽

10.14203/ab.v22i1.322 ◽

2018 ◽

Vol 22 (1) ◽

pp. 1

Author(s):

Rohmatussolihat Rohmatussolihat ◽

Puspita Lisdiyanti ◽

Yopi Yopi ◽

Yantyati Widyastuti ◽

Endang Sukara

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Culture Medium ◽

Medium Optimization ◽

Micrococcus Luteus ◽

Significant Inhibition ◽

Optimum Concentration ◽

Antimicrobial Substances ◽

Central Composite ◽

Inhibition Index

Lactic acid bacteria (LAB) are important for prevention of spoilage and pathogenic bacterial growth in foods due to their ability to generate antimicrobial substances. The objective of this study was to screen LAB for antimicrobial activity and to optimize culture medium for antimicrobial production using Response Surface Methodology (RSM) with Central Composite Design (CCD). Optimization of antimicrobial production of selected LAB was conducted with different combinations of glucose, NaCl, inoculum, and temperature. Our experimental results showed that from 129 LAB isolates, 55 showed significant inhibition against Bacillus subtilis, Escherichia coli, Micrococcus luteus, Staphylococcus aureus, Aspergillus niger, and Candida albicans. No isolates inhibited the growth of Aspergillus flavus. Lactobacillus plantarum LIPI13-2-LAB011 was selected for further study on culture medium optimization to inhibit the growth of C. albicans. From statistical analysis, the production of antimicrobial substances was significantly influenced by temperature, NaCl, and concentration of glucose. Furthermore, the optimum concentrations of glucose, concentration of inoculum, temperature, and NaCl were 1.63 %, 3.03%, 33.74°C, and 3.4%, respectively, with a maximum predicted inhibition index of 1.916, which increased 3.56-fold compared to that obtained in medium before optimization processes. The result was confirmed as when the optimum concentration of nutritions used, the inhibition index increased 3.12-fold.

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Medium Optimization for Antimicrobial Production By Newly Screened Lactic Acid Bacteria

ANNALES BOGORIENSES ◽

10.14203/ann.bogor.2018.v22.n1.1-11 ◽

2018 ◽

Vol 22 (1) ◽

pp. 1

Author(s):

Rohmatussolihat Rohmatussolihat ◽

Puspita Lisdiyanti ◽

Yopi Yopi ◽

Yantyati Widyastuti ◽

Endang Sukara

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Culture Medium ◽

Medium Optimization ◽

Micrococcus Luteus ◽

Significant Inhibition ◽

Optimum Concentration ◽

Antimicrobial Substances ◽

Central Composite ◽

Inhibition Index

Lactic acid bacteria (LAB) are important for prevention of spoilage and pathogenic bacterial growth in foods due to their ability to generate antimicrobial substances. The objective of this study was to screen LAB for antimicrobial activity and to optimize culture medium for antimicrobial production using Response Surface Methodology (RSM) with Central Composite Design (CCD). Optimization of antimicrobial production of selected LAB was conducted with different combinations of glucose, NaCl, inoculum, and temperature. Our experimental results showed that from 129 LAB isolates, 55 showed significant inhibition against Bacillus subtilis, Escherichia coli, Micrococcus luteus, Staphylococcus aureus, Aspergillus niger, and Candida albicans. No isolates inhibited the growth of Aspergillus flavus. Lactobacillus plantarum LIPI13-2-LAB011 was selected for further study on culture medium optimization to inhibit the growth of C. albicans. From statistical analysis, the production of antimicrobial substances was significantly influenced by temperature, NaCl, and concentration of glucose. Furthermore, the optimum concentrations of glucose, concentration of inoculum, temperature, and NaCl were 1.63 %, 3.03%, 33.74°C, and 3.4%, respectively, with a maximum predicted inhibition index of 1.916, which increased 3.56-fold compared to that obtained in medium before optimization processes. The result was confirmed as when the optimum concentration of nutritions used, the inhibition index increased 3.12-fold.

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Central Composite Design for Response Surface Methodology and Its Application in Pharmacy

10.5772/intechopen.95835 ◽

2021 ◽

Author(s):

Sankha Bhattacharya

Keyword(s):

Central Composite Design ◽

Response Surface ◽

Response Surface Model ◽

Fractional Factorial ◽

Surface Model ◽

Experimental Conditions ◽

Design Models ◽

Central Composite

The central composite design is the most commonly used fractional factorial design used in the response surface model. In this design, the center points are augmented with a group of axial points called star points. With this design, quickly first-order and second-order terms can be estimated. In this book chapter, different types of central composite design and their significance in various experimental design were clearly explained. Nevertheless, a calculation based on alpha (α) determination and axial points were clearly described. This book chapter also amalgamates recently incepted central composite design models in various experimental conditions. Finally, one case study was also discussed to understand the actual inside of the central composite design.

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