Predictive Model of Listeria Monocytogenes’ Growth Rate Under Different Temperatures and Acids

2006 ◽  
Vol 12 (1) ◽  
pp. 47-56 ◽  
Author(s):  
E. Carrasco ◽  
R. García-Gimeno ◽  
R. Seselovsky ◽  
A. Valero ◽  
F. Pérez ◽  
...  
Keyword(s):  
Growth Rate ◽  
Ascorbic Acid ◽  
Listeria Monocytogenes ◽  
Citric Acid ◽  
Food Industry ◽  
Inhibitory Effect ◽  
Surface Model ◽  
Physical Factors ◽  
Bias Factor ◽  
Different Temperatures

A response surface model of Listeria monocytogenes’ growth rate was built in this study under different temperatures (10 °C, 15 °C, 20 °C, 25 °C and 30 °C) and acid concentrations: citric acid (0–0.4%) and ascorbic acid (0–0.4%); two ingredients which are often used in the food industry as preservatives. Mathematical validation was performed with additional samples at different conditions within the range of the model, obtaining acceptable values of root mean square error (0.0466), standard error of prediction (18.84%), bias factor (1.05) and accuracy factor (1.16). The inhibitory effect on growth was more effective with citric acid than ascorbic acid, possibly due to the major dissociation of citric acid occurring inside microbial cells. The different conditions considered in the model will potentially allow L. monocytogenes’ response to be predicted in foods having a similar composition to the chemical and physical factors set out in this paper.

scholarly journals The Inhibitory Effect of Plant Extracts on Growth of the Foodborne Pathogen, Listeria monocytogenes

Antibiotics ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 319 ◽  
Author(s):  
Marina Ceruso ◽  
Jason A. Clement ◽  
Matthew J. Todd ◽  
Fangyuan Zhang ◽  
Zuyi Huang ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Plant Extracts ◽  
Foodborne Pathogens ◽  
Food Industry ◽  
Foodborne Pathogen ◽  
The United States ◽  
Inhibitory Effect ◽  
Microscopic Level ◽  
Natural Antimicrobials ◽  
Minimal Inhibitory Concentrations

Listeria monocytogenes is a foodborne pathogen responsible for about 1600 illnesses each year in the United States (US) and about 2500 confirmed invasive human cases in European Union (EU) countries. Several technologies and antimicrobials are applied to control the presence of L. monocytogenes in food. Among these, the use of natural antimicrobials is preferred by consumers. This is due to their ability to inhibit the growth of foodborne pathogens but not prompt negative safety concerns. Among natural antimicrobials, plant extracts are used to inactivate L. monocytogenes. However, there is a large amount of these types of extracts, and their active compounds remain unexplored. The aim of this study was to evaluate the antibacterial activity against L. monocytogenes of about 800 plant extracts derived from plants native to different countries worldwide. The minimal inhibitory concentrations (MICs) were determined, and scanning electron microscopy (SEM) was used to verify how the plant extracts affected L. monocytogenes at the microscopic level. Results showed that 12 of the plant extracts had inhibitory activity against L. monocytogenes. Future applications of this study could include the use of these plant extracts as new preservatives to reduce the risk of growth of pathogens and contamination in the food industry from L. monocytogenes.

scholarly journals Variasi Antioksidan dalam Pembuatan Protected Active Dried Yeast

2021 ◽  
Vol 19 (1) ◽  
pp. 1
Author(s):  
Ronny Purwadi ◽  
Vita Wonoputri ◽  
Febri Ulfa Fitriana ◽  
Najwa Shufia Choliq
Keyword(s):  
Ascorbic Acid ◽  
Citric Acid ◽  
Shelf Life ◽  
Death Rate ◽  
Water Solubility ◽  
Ascorbyl Palmitate ◽  
Inhibitory Effect ◽  
Co2 Production ◽  
Synthetic Antioxidants ◽  
Rate Test

Abstrak. Penggunaan antioksidan pada pembuatan protected active dried yeast (PADY) dapat memperpanjang umur simpan ragi kering. Antioksidan yang sering digunakan adalah antioksidan sintesis BHA dan BHT yang diduga bersifat karsinogenik. Penelitian ini bertujuan untuk mencari alternatif antioksidan yang lebih aman. Lima antioksidan yaitu asam sitrat, asam askorbat, tokoferol, natrium eritrobat, dan askorbil palmitat pada rentang konsentrasi 0,025-0,5% diuji pada suspensi ragiuntuk mempelajari efek inhibisi dari antioksidan tersebut. Uji laju produksi CO2 menunjukkan sifat noninhibisi dari asam askorbat, natrium eritorbat, asam sitrat, dan tokoferol, sedangkan sifat inhibisi askorbil palmitat dan BHT perlu diteliti lebih lanjut. Formulasi antioksidan terpilih untuk produksi PADY adalah asam sitrat 0,5%, asam askorbat 0,5%, dan tokoferol 0,5%. Pengeringan ragi dengan spray dryer menghasilkan PADY dengan kadar air sesuai standar. PADY dengan sifat fisik terbaik adalah variasi asam sitrat 0,5% dan asam askorbat 0,5% karena kelarutan dalam air yang baik serta granula yang lebih halus. Stabilitas vitalitas PADY diukur selama 45-50 hari, dan didapatkan PADY dengan antioksidan asam askorbat 0,5% memiliki konstanta laju kematian terendah, yaitu 0,0492/hari, setara dengan umur simpan 20 hari. Dengan demikian, formulasi antioksidan asam askorbat 0,5% berpotensi untuk dikembangkan pada produksi PADY. Kata kunci: antioksidan, ragi kering, stabilitas, vitalitas. Abstract. Variation of Antioxidant in Production of Protected Active Dried Yeast. The use of antioxidants in production of protected active dried yeast (PADY) can increase dried yeast’s shelf life. Usually, the antioxidants used are synthetic antioxidants such as BHA and BHT, which are known to be carcinogenic. Therefore, the aim of this research is to study antioxidant alternative that is safer. Five antioxidants, i.e. citric acid, ascorbic acid, tocopherol, sodium erythorbate, and ascorbyl palmitate in concentration range of 0.025-0.5% were tested on yeast suspension to study its inhibitory effect. CO2 production rate test showed noninhibitory characteristic of ascorbic acid, sodium erythorbate, citric acid, and tocopherol, whereas ascorbyl palmitate and BHT showed inhibitory characteristic. Formulations of antioxidants selected are 0.5% citric acid, 0.5% ascorbic acid, and 0.5% tocopherol. Spray drying of yeast resulted in PADY with moisture content within standard. PADYs with the best physical properties are 0.5% citric acid and 0.5% ascorbic acid variation due to good water solubility and finer granules. Vitality stability of PADY was measured for 45-50 days. PADY with 0.5% ascorbic acid had the lowest death rate constant, i.e. 0.0492/day, which is equivalent to 20-days shelf life. Thus, ascorbic acid antioxidant formulation of 0.5% can be developed in the production of PADY. Keywords: antioxidant, dried yeast, stability, vitality.

scholarly journals Efecto d Baño Químico Con Ácido Cítrico y Ascórbico, Temperatura y Tiempo de Almacenamiento Sobre el Pardeamiento Enzimático en Persea Americana Mínimamente Procesada

2021 ◽  
Vol 17 (37) ◽  
pp. 247
Author(s):  
Lurys Ivette Martínez Marín ◽  
Angie Macías
Keyword(s):  
Ascorbic Acid ◽  
Food Safety ◽  
Citric Acid ◽  
Organic Acids ◽  
Significant Loss ◽  
Persea Americana ◽  
Enzymatic Browning ◽  
Minimally Processed ◽  
Different Temperatures ◽  
Loss Of Mass

Se evaluó el efecto de los ácidos orgánicos sobre el pardeamiento enzimático de la Persea americana variedad Hass, mínimamente procesada, empacada al vacío y almacenada a distintas temperaturas. Las muestras de aguacate se trataron con un baño químico de ácidos orgánicos (ácido cítrico y ácido ascórbico) con tres concentraciones diferentes, luego se empacaron al vacío y fueron almacenadas a 4° y 8° C durante 12 días. Muestras sin tratamiento se emplearon como control y todas las muestras se evaluaron cada 0, 4, 8 y 12 días. Se concluye que a 8°C el color y el sabor del aguacate mejora. Durante cada observación no hubo pérdida significativa de masa. Estos resultados, aunque incipientes, son útiles porque pueden contribuir con la seguridad alimentaria, además de determinar nuevas formas de preservar Persea americana y poder comercializarla como un producto de cuarta gama. The effect of organic acids on the enzymatic browning of Persea americana variety Hass, minimally processed, vacuum packed and stored at different temperatures, was evaluated. The avocado samples were treated with a chemical bath of organic acids (citric acid and ascorbic acid) with three different concentrations, then they were vacuum packed and stored at 4 ° and 8 ° C for 12 days. Untreated samples were used as control and all samples were evaluated at 0, 4, 8 and 12 days. It is concluded that at 8 ° C the color and flavor of the avocado improves; the chemical bath that obtained the best results was chemical bath 3 with respect to color and the samples are best preserved on day 8. During each observation there was no significant loss of mass. These results, although incipient, are useful because they can contribute to food safety, in addition to determining new ways of preserving Persea americana and being able to market it as a fourth-range product.

Chemical Preservatives Action on Microbial Growth in a Model System of Refrigerated Prepeeled Potatoes

1993 ◽  
Vol 56 (9) ◽  
pp. 801-807 ◽  
Author(s):  
L. GIANNUZZI ◽  
N. E. ZARITZKY
Keyword(s):  
Ascorbic Acid ◽  
Citric Acid ◽  
Storage Time ◽  
Microbial Growth ◽  
Total Concentration ◽  
Inhibitory Effect ◽  
Model System ◽  
Sodium Bisulfite ◽  
Chemical Preservatives ◽  
Aerobic And Anaerobic

The effect of different concentrations of citric acid and ascorbic acid (applied individually or in mixture's) on microbial growth in potato homogenate was analyzed and compared to the sodium bisulfite action during storage at 4°C in low gaseous permeability films. These experiments allowed one to simulate the behavior of prepeeled potatoes but with a known amount of added preservative to evaluate additive or synergic effects. Total viable microorganisms, Enterobacteriaceae, Pseudomonas sp., Lactobacillus sp., molds, yeasts, Clostridium sulfite reducers, psychrotropic microorganisms, and aerobic and anaerobic viable spores were analyzed during storage time. Inhibition indexes produced by the tested preservatives were calculated for the different microorganisms. Sodium bisulfite solutions (100 ppm) had no inhibitory effect. Concentrations of 3,500 ppm citric acid and 10,000 ppm ascorbic acid showed antimicrobial action as well as mixtures of citric acid/ascorbic acid of the following compositions (in terms of total acids concentration): 2,700/2,000, 3,500/2,000, and 2,700/3,000 ppm. A higher effect on Enterobacteriaceae was observed in comparison with other microorganisms. The apparent synergic effect of these acids when they were applied together was demonstrated to be actually an additive effect when concentrations of undissociated acid in the mixtures were considered instead of total concentration.

Development and Validation of Growth Model for Yersinia enterocolitica in Cooked Chicken Meats Packaged under Various Atmosphere Packaging and Stored at Different Temperatures

2001 ◽  
Vol 64 (7) ◽  
pp. 987-993 ◽  
Author(s):  
Q. K. WEI ◽  
T. J. FANG ◽  
W. C. CHEN
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Yersinia Enterocolitica ◽  
Specific Growth ◽  
Modified Atmosphere Packaging ◽  
Growth Curves ◽  
Gompertz Model ◽  
Lag Time ◽  
Bias Factor ◽  
Different Temperatures

Mathematical models that can predict the growth of Yersinia enterocolitica in chicken meats were evaluated in this study. The growth curves for Y. enterocolitica in chicken meats variously packaged (air, vacuum, and modified atmosphere packaging [MAP]) and stored at various temperatures (4, 10, 16, 22, 28, and 34°C) were constructed. The Gompertz model was applied to fit each of the experimental curves for the conditions mentioned above. The variations in the parameters, including lag time (λ) and specific growth rate (μ), at various temperatures were then described by the following models: the variations in lag time were described by the Adair and Smith models and the variations in the specific growth rate were described by the Ratkowsky and Zwietering models. The various models were then compared using graphical and mathematical analyses such as mean square error (MSE), regression coefficient (r2), bias factor, and accuracy factor. The results indicate that the mean r values in the Gompertz model for chicken meats packaged in air, vacuum, and MAP were 0.99, 0.99, and 0.95, respectively. The lag time modeled with the Adair and Smith functions exhibited a greater variance and demonstrated larger errors. The MSEs were 0.0015 and 0.0017 for Ratkowsky and Zwietering models, respectively. The r2 values in the Ratkowsky and Zwietering models were both 0.99. The bias factor was 1.017 for the Ratkowsky model and 1.096 for the Zwietering model. The accuracy factor of the Zwietering model was 1.174, which was lower than that in the Ratkowsky model (1.275), indicating that the former model was more accurate than the latter in predicting the specific growth rate of Y. enterocolitica in chicken meats.

Growth/no growth model of Listeria monocytogenes as a function of temperature, pH, citric acid and ascorbic acid

2006 ◽  
Vol 224 (1) ◽  
pp. 91-100 ◽  
Author(s):  
A. Valero ◽  
E. Carrasco ◽  
F. Pérez-Rodriguez ◽  
R. M. García-Gimeno ◽  
G. Zurera
Keyword(s):  
Ascorbic Acid ◽  
Listeria Monocytogenes ◽  
Citric Acid ◽  
Growth Model

scholarly journals Comparative Analysis of Flour Properties of Dioscorea alata Tuber And Its Utilization On Wet Noodle

2019 ◽  
Vol 1 (2) ◽  
pp. 70-75
Author(s):  
Lavlinesia Lavlinesia
Keyword(s):  
Ascorbic Acid ◽  
Citric Acid ◽  
Acid Solution ◽  
Food Industry ◽  
Dioscorea Alata ◽  
Citric Acid Solution ◽  
Ascorbic Acid Solution ◽  
Random Design ◽  
The World ◽  
Flour Properties

Abstract— Dioscorea alata grown in many areas of the world has been intensively studied.  However none of Indonesian cultivar has been intensively studied for their properties and its utilization in food industry. This research was aimed to compare the properties of purple Dioscorea alata’s flour produced using different methods and to study the effect of partly substituted wheat by purple Dioscorea alata’s flour on the characteristic of wet noodles. The research on the properties of purple Dioscorea alata’s flour was conducted using complete random design with treatment on the methods used to produce flour: control, steaming, soaking in 1% citric acid solution + steaming, blanching + soaking in 1% citric acid solution + steaming and blanching + soaking in 2% ascorbic acid solution + steaming.These 5 methods were repeated 4 times. The research on utilization of Dioscoreaalata’s flour on wet noodle was conducted using complete random design with 5 levels of treatment (0%, 10%, 20%, 30%, and 40% of Dioscorea alata’s flour) and 4 replications.   The result showed that steaming the slices of tuber for 7 minutes prior to drying was an effective method to produce flour with strong natural color of purple. The concentration of Dioscorea alata’s flour significantly affects the elongation and texture of noodle (p<0.05).   Except for its unpleasant grey color, wet noodle can be produced using up to 40% Dioscorea alata’s flour.

Inhibitory Effect of Ascorbic Acid 2-O-.ALPHA.-Glucoside on the Pigmentation of Skin by Exposure to Ultraviolet Light.

1996 ◽  
Vol 58 (3) ◽  
pp. 439-443 ◽  
Author(s):  
Eriko MIYAI ◽  
Itaru YAMAMOTO ◽  
Jun-ichi AKIYAMA ◽  
Mitsuhiro YANAGIDA
Keyword(s):  
Ascorbic Acid ◽  
Ultraviolet Light ◽  
Inhibitory Effect

scholarly journals Green extraction of proteins, umami and other free amino acids from brown macroalgae Ascophyllum nodosum and Fucus vesiculosus

2021 ◽  
Author(s):  
Viruja Ummat ◽  
Marco Garcia-Vaquero ◽  
Mahesha M. Poojary ◽  
Marianne N. Lund ◽  
Colm O’Donnell ◽  
...  
Keyword(s):  
Amino Acids ◽  
Citric Acid ◽  
Free Amino Acids ◽  
Free Amino ◽  
Food Industry ◽  
Ascophyllum Nodosum ◽  
Fucus Vesiculosus ◽  
Green Solvents ◽  
Brown Macroalgae ◽  
Extraction Solvent

AbstractSeaweeds are a valuable potential source of protein, as well as free amino acids (FAAs) with umami flavour which are in high demand by the food industry. The most commonly used flavouring agents in the food industry are chemically synthesised and therefore are subject to concerns regarding their safety and associated consumer resistance. This study focuses on the effects of extraction time (1 and 2 h) and solvents (0.1 M HCl, 1% citric acid and deionised water) on the extraction of protein and FAAs including umami FAAs from Irish brown seaweeds (Ascophyllum nodosum and Fucus vesiculosus). Extraction yields were influenced by both the extraction solvent and time, and also varied according to the seaweed used. Both seaweeds investigated were found to be good sources of protein, FAAs including umami FAAs, demonstrating potential application as flavouring agents in the food industry. Overall, the use of green solvents (deionised water and citric acid) resulted in higher recoveries of compounds compared to HCl. The results of this study will facilitate the use of more sustainable solvents in industry for the extraction of proteins and flavouring agents from seaweed.

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