Bioluminescent ATP Assay for Rapid Estimation of Microbial Numbers in Fresh Meat

1986 ◽  
Vol 49 (1) ◽  
pp. 18-22 ◽  
Author(s):  
KENNETH J. LITTEL ◽  
SYLVIA PIKELIS ◽  
ARNOLD SPURGASH
Keyword(s):  
Bacterial Flora ◽  
Meat Products ◽  
Sampling Procedure ◽  
Plate Count ◽  
Meat Sample ◽  
Fresh Meat ◽  
Atp Assay ◽  
Plate Counts ◽  
Food Particles ◽  
Double Filtration

The utility of a bioluminescence adenosine triphosphate (ATP) procedure to estimate bacterial levels in fresh meat products was investigated. A double filtration (DF) sampling procedure was used. In this system two filters were fitted in tandem. A prefilter was used to trap food particles which contained contaminating ATP while the second filter retained the microbial population. The second filter was treated with an enzyme reagent to hydrolyze nonmicrobial ATP that was present on the bacterial filter. Using standard curves, that related bacterial ATP (B-ATP) and plate counts, the bacterial ATP levels in fresh beef and chicken samples were transformed into estimated bacterial levels in the products. The ATP procedure was able to predict bacterial levels within +/− 0.5 log10 of the actual plate count for greater than 90% of the fresh beef and chicken samples tested. Mean femtogram (fg) ATP/CFU levels in fresh beef and chicken mixed bacterial flora were 0.88 and 0.94, respectively. Minimal sensitivity of the double filtration/enzyme method was approximately 5 × 104 CFU/g of meat sample.

scholarly journals Combined Effect of Microencapsulated Horseradish Juice and High-Pressure Treatment on Pork Quality During Storage

2021 ◽  
Vol 75 (6) ◽  
pp. 463-468
Author(s):  
Sanita Sazonova ◽  
Lolita Tomsone ◽  
Ruta Galoburda ◽  
Ilze Grāmatiņa ◽  
Thierry Talou
Keyword(s):  
High Pressure ◽  
Water Activity ◽  
Meat Products ◽  
Antimicrobial Properties ◽  
High Pressure Processing ◽  
Plate Count ◽  
Meat Sample ◽  
Pressure Treatment ◽  
Pork Meat ◽  
High Pressure Treatment

Abstract High-pressure processing (HPP) is well suited to combine consumer demand for meat products with minimal heat treatment without compromising product safety. In turn, herbs have antioxidant and antimicrobial properties. The aim of this study was to evaluate the application of hurdle technology combining microencapsulated horseradish root and leaf juice with HPP (300 MPa; 15 min) for extending of the raw pork meat shelf life. Water activity (aw), pH, colour, hardness, and micro-biological parameters of meat were evaluated during 21-day storage. Total plate count (TPC) in HPP treated samples was significantly smaller (p < 0.05) compared to untreated samples during storage until the day 14. On day 21, the TPC in processed samples was still slightly lower, however, at this point significance was not established between samples. Water activity dynamics in the HPP-treated microencapsulated pork meat samples differed significantly from other samples. Hardness decreased during storage, but no significant differences were found between samples. The L* values and pH of the meat were not significantly influenced by the added microencapsulated juice, but by high pressure treatment. Treatment with microencapsulated horseradish juice had a positive effect on the TPC and aw of the meat sample.

scholarly journals Efficacy of Cetylpyridinium Chloride against Listeria monocytogenes and Its Influence on Color and Texture of Cooked Roast Beef†

2005 ◽  
Vol 68 (11) ◽  
pp. 2349-2355 ◽  
Author(s):  
M. SINGH ◽  
H. THIPPAREDDI ◽  
R. K. PHEBUS ◽  
J. L. MARSDEN ◽  
T. J. HERALD ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Listeria Monocytogenes ◽  
Lactic Acid Bacteria ◽  
Cetylpyridinium Chloride ◽  
Meat Products ◽  
Plate Count ◽  
Bacterial Populations ◽  
Plate Counts ◽  
Roast Beef ◽  
Aerobic Plate Count

Sliced (cut) and exterior (intact) surfaces of restructured cooked roast beef were inoculated with Listeria monocytogenes, treated with cetylpyridinium chloride (CPC; immersion in 500 ml of 1% solution for 1 min), individually vacuum packaged, and stored for 42 days at 0 or 4°C. Noninoculated samples were similarly treated, packaged, and stored to determine effects on quality (color and firmness) and on naturally occurring bacterial populations, including aerobic plate counts and lactic acid bacteria. Immediately after CPC treatment, regardless of inoculation level, L. monocytogenes populations were reduced (P = 0.05) by about 2 log CFU/cm2 on sliced surfaces and by about 4 log CFU/cm2 on exterior surfaces. Throughout 42 days of refrigerated storage (at both 0 and 4°C), L. monocytogenes populations on CPC-treated samples remained lower (P = 0.05) than those of nontreated samples for both surface types. After 42 days of storage at both 0 and 4°C, aerobic plate count and lactic acid bacteria populations of treated samples were 1 to 1.5 log CFU/cm2 lower (P = 0.05) than those of nontreated samples for both surface types. CPC treatment resulted in negligible effects (P &gt; 0.05) on the color (L*, a*, and b* values) of exterior and sliced roast beef surfaces during storage. For both sliced and exterior surfaces, CPC-treated samples were generally less firm than nontreated samples. CPC treatment effectively reduced L. monocytogenes populations on roast beef surfaces and resulted in relatively minor impacts on color and texture attributes. CPC treatment, especially when applied to products prior to slicing, may serve as an effective antimicrobial intervention for ready-to-eat meat products.

Bioluminescence ATP Assay for Estimating Total Plate Counts of Surface Microflora of Whole Cantaloupe and Determining Efficacy of Washing Treatments†

2001 ◽  
Vol 64 (6) ◽  
pp. 813-819 ◽  
Author(s):  
DIKE O. UKUKU ◽  
VLASTA PILIZOTA ◽  
GERALD M. SAPERS
Keyword(s):  
Hydrogen Peroxide ◽  
Count Data ◽  
Microbial Load ◽  
Plate Count ◽  
Atp Level ◽  
Atp Assay ◽  
Atp Levels ◽  
Plate Counts ◽  
Lower Correlation ◽  
Linear Correlations

The surface microflora of cantaloupes were estimated using a bioluminescence ATP assay, and results were compared to plate count data. Cantaloupes were treated as follows: (i) water washed, or (ii) washed in solutions of sodium hypochlorite (1,000 mg/liter) or hydrogen peroxide (5%) for 5 min. Bioluminescence ATP assay results showed differences in ATP level/cm2 of cantaloupes dipped in chlorine or hydrogen peroxide solution; ATP levels in these washed samples were lower than in controls due to antimicrobial action of the treatments on the cantaloupe surface. Linear correlations were found between the bioluminescence ATP assay and aerobic plate counts of unwashed cantaloupe (r2 = 0.995) and those washed with water (r2 = 0.990) determined before storage. Lower correlations between the bioluminescence ATP assay and the aerobic plate counts were observed on cantaloupes stored for 120 h at 20°C (r2 = 0.751) than at 4°C (r2 = 0.980) without washing treatment. Lower correlation at 20°C may be the result of clusters or growth that occurred in chains. ATP levels of washed cantaloupes correlated well with bacterial plate counts (r2 = 0.999). A reliable minimum detectable threshold using the bioluminescence ATP assay was established at 3 log10 fg/cm2 corresponding to 4 log10 CFU/cm2. Bioluminescence ATP assay is not recommended for washed samples where the microbial load is near or below the threshold. Therefore, the bioluminescence ATP assay will be recommended for quick estimation of total microbial load on cantaloupe surfaces where the population is expected to exceed this threshold. The assay can save the industry time by eliminating the required incubation required by the conventional methods.

Bacterial Flora of Fish from Tropical Sea Water

1979 ◽  
Vol 42 (9) ◽  
pp. 724-728 ◽  
Author(s):  
LUIS ROBERTO DE LEON FAJARDO ◽  
E. H. MARTH
Keyword(s):  
Major Part ◽  
Sea Water ◽  
Bacterial Flora ◽  
Plate Count ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
Fresh Fish ◽  
Plate Counts ◽  
Aerobic Plate Count ◽  
Tropical Sea

Five lots of fish were examined microbiologically for aerobic plate count at 10 and 30 C. coliform and enterococcus counts, presence of coagulase-positive Staphylococcus aureus and genera of bacteria appearing on the aerobic plates. After initial analyses. fish were stored in ice, held there for a week and then aerobic plate counts and isolation of colonies for identification as to genus were done again. Aerobic plate counts ranged from 104 to 107 per gram of skin at the beginning of storage in ice and increased to 106 to 109 per gram at the end of 7 days of storage. Coliforms and enterococci were found in fresh fish but no S. aureus was detected. Gram-negative bacteria accounted for about half of the bacteria on fresh fish, predominated as spoilage advanced and eventually formed the major part of the flora. Pseudomonas, Moraxella and Alcaligenes were the principal genera of gram-negative bacteria at the end of storage.

scholarly journals IDENTIFICATION AND INHIBITION OF BIOACTIVE COMPOUNDS FROM NUTMEG ( Myristica fragrans Houtt ) AND THE APPLICATION AS ANTIBACTERIAL AGENT

2018 ◽  
Vol 4 (3) ◽  
pp. 191
Author(s):  
Dede Zaenal Arief ◽  
Hervelly Velly
Keyword(s):  
Antimicrobial Agent ◽  
Meat Products ◽  
Plate Count ◽  
Gram Positive ◽  
Fresh Meat ◽  
Bacteria Growth ◽  
Main Research ◽  
Antimicrobial Substances ◽  
Spoilage Bacteria ◽  
Myristica Fragrans Houtt

The purpose of this research is to determine the most effective of nutmeg meat products to inhibit the specific spoilage bacteria based on inhibitory zone and determine the power of antibacterial compounds in nutmeg meat to  inhibit and kill specific spoilage bacteria  based on the number of growth  of spoilage bacteria. This research consists of two stages: The purpose of first stage is to determine  the most effective of nutmeg meat products as an antimicrobial agent to inhibit gram-positive and gram-negative bacteria with inhibition test response. The second stage of the main research continued from  preliminary research that consists of three steps. The purpose of first step is to determine  the best long immersion antimicrobial substances against bacteria growth in fresh meat for 0 minute, 5 minutes, 10 minutes, 15 minutes and 20 minutes. The purpose of second step is to determine the correlation between the concentration of antimicrobial agent 5%, 10%, 15%, 20% and 25% of the microbial growth number in fresh meat stored within 5 days. The analysis was performed using total plate count method. The purpose of third  step is to determine the level of concentration that is acceptable to consumers. Based on the results of research was obtained that the nutmeg meat essential oil can inhibit the growth of gram positive and negative bacteria. If concentration of antimicrobial substances are higher, so that the power of inhibit to against spoilage bacteria  in fresh meat is higher. The selected concentration by organoleptic test that acceptable by consumers is 10%.

A Review of Aerobic and Psychrotrophic Plate Count Procedures for Fresh Meat and Poultry Products

2002 ◽  
Vol 65 (7) ◽  
pp. 1200-1206 ◽  
Author(s):  
J. M. JAY
Keyword(s):  
Low Temperature ◽  
Incubation Temperature ◽  
Plate Count ◽  
Fresh Meat ◽  
Poultry Products ◽  
Plate Count Agar ◽  
Plate Counts ◽  
Incubation Temperatures ◽  
Temperature Time ◽  
Yeast Extract Agar

This is a review of reports that employed aerobic plate counts on fresh meat and poultry products since 1985; it lists synopses of 100 applications. A total of 15 different plating media were used, with 48 (48%) being either plate count agar (PCA) or tryptone glucose yeast extract agar. The temperature-time relations ranged from a low temperature of 20°C for 120 h to 37°C for 24 h. Some 29 different temperature-time combinations were used among the total of 109, with 21 (19.3%) being 35°C/48 h, followed by 12 (11.0%) at 32°C/48 h, 11 (10.1%) at 25°C/48 h, and 9 (8.3%) at 25°C/72 h. Fifty-four (49.5%) plate count applications employed incubation temperatures of 30°C and below. From the 26 reports that employed psychrotrophic counts, 16 (61.5%) used PCA; 18 different temperature-time combinations were used, with 7°C/10 d employed by only four. Twenty-one (80.8%) employed an incubation temperature at or &lt;10°C, and five employed an incubation temperature &gt;10°C. There is a serious need for some consensus on methodologies for aerobic and psychrotrophic counts on fresh meat and poultry products.

A Method for Decreasing Sampling Variance in Bacteriological Analyses of Meat Surfaces1,2

1980 ◽  
Vol 43 (1) ◽  
pp. 21-22 ◽  
Author(s):  
M. E. ANDERSON ◽  
J. L. SEBAUGH ◽  
R. T. MARSHALL ◽  
W. C. STRINGER
Keyword(s):  
Sample Variance ◽  
Sampling Variance ◽  
Fresh Meat ◽  
Plate Counts

Viable counts of bacteria are often high in some areas and low in adjacent areas of the same surface of fresh meat. The present study indicated that rubbing meat surfaces together before sampling reduces variation among bacterial plate counts of pieces of beef plate meat. Counts before rubbing ranged from 2 to 6,187/cm2, whereas counts after rubbing ranged from 15 to 2,043/cm2. The reduced sample variance allowed for fewer samples to be taken in studies of cleaning and sanitizing of fresh beef.

Enumeration of Lactobacillus acidophilus with the Agar Plate Count

1978 ◽  
Vol 41 (6) ◽  
pp. 439-442 ◽  
Author(s):  
E. B. COLLINS
Keyword(s):  
Lactobacillus Acidophilus ◽  
Agar Plate ◽  
Plate Count ◽  
Distilled Water ◽  
Anaerobic Conditions ◽  
Dry Ice ◽  
Standard Methods ◽  
Plate Counts

Higher plate counts on MRS agar were obtained under anaerobic conditions for three of four strains of Lactobacillus acidophilus and commercially prepared nonfermented acidophilus milks (products A and B) made with two of the strains. Average values for aerobic counts of products A and B were 87 and 60%, respectively, of those for corresponding anaerobic counts. Incubation of plates poured with MRS agar for 72 ± 3 h at 37 C was sufficient for maximal counts. Two strains and the nonfermented acidophilus milks gave highest counts on Standard Methods Agar (SMA). Greatest numbers of bile-resistant colonies were indicated by MRS agar (with 0.2% oxgall). The average of plate counts for products A and B determined on MRS agar with oxgall was 65% of that for corresponding plate counts determined on MRS without oxgall. Buffered distilled water, 0.9% NaCl, and 1% peptone each served satisfactorily as diluent. Overlaying MRS agar in poured plates with additional medium was not advantageous. Plate counts of samples that had been frozen and stored at −26 C or in dry ice were as high as those of duplicate samples that had been stored at 1.7 C.

The Microbiological Quality of Honey as Determined by Aerobic Colony Counts

1993 ◽  
Vol 56 (4) ◽  
pp. 336-337 ◽  
Author(s):  
JOSEP SERRA BONVEHI ◽  
ROSSEND ESCOLÁ JORDÁ
Keyword(s):  
Membrane Filter ◽  
Microbiological Quality ◽  
Plate Count ◽  
Filter Method ◽  
Filter Methods ◽  
Plate Counts ◽  
Multifloral Honey ◽  
Plate Count Method ◽  
Membrane Filter Method

The number of mesophilic aerobic colonies was determined in 72 samples of mono- and multifloral honey from various sources by the plate count and the membrane filter methods. The presence of motile colonies made the plate counts unreliable. The microorganism producing these colonies was identified as Bacillus alvei. Colony counts could only be carried out in 27 of the samples when using the plate count method, while with the membrane filter method the number of colonies was counted in all the samples.

Comparison of the Petrifilm™ Yeast and Mold Culture Film Method to Conventional Methods for Enumerating Yeasts and Molds in Foods

1991 ◽  
Vol 54 (6) ◽  
pp. 443-447 ◽  
Author(s):  
L. R. BEUCHAT ◽  
B. V. NAIL ◽  
R.E. BRACKETT ◽  
T. L. FOX
Keyword(s):  
Correlation Coefficients ◽  
Food Group ◽  
Black Pepper ◽  
Plate Count ◽  
Food Groups ◽  
Plate Count Agar ◽  
Plate Counts ◽  
Yeasts And Molds ◽  
Potential Food ◽  
Film Method

Petrifilm™ Yeast and Mold (YM) plates were compared to acidified potato dextrose agar (APDA) and chloramphenicol-supplemented plate count agar (CPCA) for its suitability to enumerate yeasts and molds in 13 groups of food products. These products consisted of beans (dry and frozen, green), corn meal, flour (wheat), fruit (apple), a meat/vegetable entree (chicken pot pie), a precooked meat (beef), milk (dehydrated, nonfat), nuts (pecans), pasta, potatoes (dehydrated), precooked sausage, and a spice (black pepper). Correlation coefficients of Petrifilm™ YM plates versus APDA and CPCA pour plates for recovering total yeasts and molds from a composite of the thirteen test foods were, respectively, 0.961 and 0.974. Individually, Petrifilm™ YM plate counts were equivalent or higher than APDA and CPCA for some food groups and lower for other food groups. Because food particle interference can make enumeration of yeast and mold colonies on Petrifilm™ YM plates difficult for some food groups, potential food interference will need to be evaluated for each food group tested.

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