Effect of Aerobic Storage before Vacuum Packaging on the pH, Color and Bacterial Flora of Beef1

1983 ◽  
Vol 46 (4) ◽  
pp. 287-291 ◽  
Author(s):  
E. A. FOEGEDING ◽  
H. D. NAUMANN ◽  
W. C. STRINGER

Beef was stored aerobically for 2 or 6 d at 1 ± 1°C before vacuum packaging. Total numbers of aerobic bacteria, Pseudomonas spp., Brochothrix thermosphacta and lactic acid bacteria were determined by selectively plating stored samples. Meat color was evaluated with a color difference meter and a color panel. Aerobic plate counts, numbers of pseudomonads and B. thermosphacta, and pH each were higher in samples held aerobically for 6 d compared with those held aerobically for 2 d. The major effect of delayed vacuum packaging was to slow the growth of lactic acid bacteria and minimize the number of pseudomonads. The variation among treatments was similar in Pseudomonas spp. population for 21 d and in pH for 7 d, and there was no significant effect of packaging treatment in color. Results indicate that the initial treatment variations were lost as storage time progressed.

1985 ◽  
Vol 48 (9) ◽  
pp. 765-769 ◽  
Author(s):  
C. VANDERZANT ◽  
M. O. HANNA ◽  
J. G. EHLERS ◽  
J. W. SAVELL ◽  
D. B. GRIFFIN ◽  
...  

The effect of various initial chilling treatments on the numbers and types of microorganisms of beef, pork and lamb tongues (n = 60) and livers (n = 60) packaged either in polyethylene (PE) film or in vacuum packages in Texas and transported fresh-chilled via transoceanic shipment to Antwerp, Belgium, was evaluated. Initial chilling treatments included: cooler-tempered (4 to 6 h at 2°C), cooler-chilled (24 h at 2°C) freezer-tempered (0.5 to 1 h at −20°C), freezer-chilled (2 h at −20°C), ice-chilled (2 h in ice water slush) and no prechilling (NPC) before packaging and subsequent refrigerated storage at 2°C. After the initial chilling treatments, the microflora was varied with Micrococcus spp. with or without coryneform bacteria being the predominant bacterial types of most samples. After refrigerated storage for 13 to 15 d, lactic acid bacteria became dominant in most vacuum-packaged samples and in pork and lamb samples stored in PE film. Brochothrix thermosphacta and Pseudomonas spp. constituted a greater part of the microflora of beef tongues and livers stored in PE film than that of comparable vacuum-packaged samples. Increases in aerobic plate counts (APC) of refrigerated vacuum-packaged samples nearly always were greatest for samples (NPC) that were not pre-chilled before packaging and usually were smallest for samples that were either freezer-chilled, freezer-tempered or ice-chilled.


1993 ◽  
Vol 56 (8) ◽  
pp. 689-693 ◽  
Author(s):  
G. G. GREER ◽  
B. D. DILTS ◽  
L. E. JEREMIAH

The effects of prolonged, anoxic storage, under CO2 at −1.5°C, upon the bacteriology and case life of pork on its subsequent transfer to the aerobic conditions of simulated retail display at 8°C was examined. Brochothrix thermosphacta, lactic acid bacteria, enterics, and pseudomonads were enumerated. Panel scores for odor and appearance acceptability were used to quantify retail case life. Lactic acid bacteria were the only bacteria found during loin storage in CO2 for up to 24 weeks. Those organisms reached maximum number of 107 CFU/cm2 within 9 weeks. The number of lactic acid bacteria initially found on the freshly cut surfaces of loin chops increased linearly during the first 9 weeks of loin storage in CO2. Thereafter, they continued to grow on the chops and dominated the spoilage flora during retail display. The pseudomonads grew rapidly and emerged as the next most numerous organism, while B. thermosphacta and enterics showed only limited aerobic growth. The acceptability of pork chop appearance and odor was adversely affected by loin storage time. Each 6-week interval of loin storage produced a 1 d reduction in case life. Should controlled atmospheres be a practicable means of meat distribution to the retail marketplace, efforts will be necessary to assure a maximum case life after their removal from preservative packagings.


1981 ◽  
Vol 44 (11) ◽  
pp. 866-869 ◽  
Author(s):  
INGER ERICHSEN ◽  
GÖRAN MOLIN

Beef of high pH (6.6) and of normal pH (5.8) was packed in air, a mixture of 78% N2 + 20% CO2 + 2% 02, vacuum, and 100% CO2 and stored at 4 C. The effect of the different gas environments on development of the microbial flora of the two types of beef was examined. The shelf-life increased in the order: pure CO2 > vacuum > gas mixture (20% CO2 > air. After storage in air for 14 days, Pseudomonas spp. comprised 76% of the flora on the normal beef and 88% of the flora on the high pH beef. In the gas mixture, after 21 days the microbial flora on the normal beef was dominated by lactic acid bacteria (52%), Enterobacteriaceae (16 %) and coryneforms (16 %) while the high pH beef contained Pseudomonas spp. (44 %), lactic acid bacteria (28%) and Brochothrix thermosphacta (28%). In the vacuum, after 21 days 96% of the flora in normal beef consisted of lactic acid bacteria, whereas 60% lactic acid bacteria and 40% B. thermosphacta were found on the high pH beef. In pure CO2, stored for 51 days, both the normal and high pH beef were completely dominated by lactic acid bacteria.


Foods ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2980
Author(s):  
Tareq M. Osaili ◽  
Fayeza Hasan ◽  
Anas A. Al-Nabulsi ◽  
Dinesh Kumar Dhanasekaran ◽  
Reyad Shaker Obaid ◽  
...  

The use of essential oils (EOs) and/or vacuum packaging (VP) with meats could increase product shelf-life. However, no studies investigating the effect of EOs and VP on camel meat background microbiota have been conducted previously. The study aimed to analyze the antimicrobial effect of essential oils (EOs) carvacrol (CA), cinnamaldehyde (CI), and thymol (TH) at 1 or 2% plus vacuum packaging (VP) on the growth of spoilage-causing microorganisms in marinated camel meat chunks during storage at 4 and 10 °C. VP is an effective means to control spoilage in unmarinated camel meat (CM) and marinated camel meat (MCM) compared to aerobic packaging (AP). However, after EO addition to MCM, maximum decreases in spoilage-causing microorganisms were observed under AP on day 7. Increasing the temperature from 4 to 10 °C under AP increased the rate of spoilage-causing bacterial growth in CM and MCM; however, EOs were more effective at 10 °C. At 10 °C the maximum reductions in total mesophilic plate counts, yeast and molds, mesophilic lactic Acid bacteria, Enterobacteriaceae, and Pseudomonas spp. were 1.2, 1.4, 2.1, 3.1, and 4.8 log CFU/g, respectively. Incorporating EOs at 2% in MCM, held aerobically under temperature abuse conditions, delayed spoilage.


2009 ◽  
Vol 72 (11) ◽  
pp. 2278-2283 ◽  
Author(s):  
A. R. HOYLE ◽  
J. C. BROOKS ◽  
L. D. THOMPSON ◽  
W. PALMORE ◽  
T. P. STEPHENS ◽  
...  

Lactic acid bacteria (LAB) can decrease numbers of Escherichia coli O157:H7 and Salmonella in ground beef during storage. Two dose-titration studies were conducted in ground beef to determine dose levels of LAB needed to inhibit the pathogens. A second study evaluated whether LAB masked changes typically associated with the spoilage of ground beef displayed under refrigerated (0°C) or abusive (10°C) temperatures packaged in both traditional overwrap (TOP) and modified atmosphere packaging (MAP; 80% O2–20% CO2). Microbial analyses were conducted to determine spoilage endpoints and pathogen reduction. In the dose-titration study, Salmonella was reduced by 3 log cycles at all doses (106,107, and 108 LAB per g) after 3 days of storage and was eliminated after 5 days of storage. E. coli O157:H7 was reduced by 2 log cycles at all dosages after 3 days of storage and by 3 log cycles after 5 days of storage. In the spoilage studies, as expected, total aerobic plate counts and LAB populations in LAB-inoculated samples were higher than the controls initially, but the counts were similar near the end of the study. While total spoilage bacteria generally increased over time, very few differences existed between treatments stored at 0°C and 10°C in coliforms , Brochothrix thermosphacta, yeasts and molds, and Pseudomonas spp. counts for both the TOP and MAP samples. We conclude that LAB could potentially be added to ground beef in TOP and MAP as a processing intervention for E. coli O157:H7 and Salmonella without masking microbial spoilage characteristics.


2018 ◽  
Vol 7 (4) ◽  
pp. 1 ◽  
Author(s):  
Xianqin Yang ◽  
Julia Devos ◽  
Hui Wang ◽  
Mark Klassen

The second national baseline microbiological survey of beef steaks offered for retail in Canada was conducted in 2015. A total of 621 steaks of four types (cross rib, CR; inside round, IR; striploin, SL; top sirloin, TS) collected from 135 retail stores in five cities across Canada were tested. Swab samples each from swabbing the entire upper surface of each steak were processed for enumeration of seven groups of indicator organisms: total aerobes (AER), psychrotrophs (PSY), lactic acid bacteria (LAB), pseudomonads (PSE), Brochothrix thermosphacta (BRO), coliforms (COL) and Escherichia coli (ECO). The overall mean values (log CFU/100 cm2) were 5.17±1.29, 4.92±1.36, 4.79±1.42, 3.26±1.49, 2.34±1.88, and 0.80±1.05 for AER, PSY, LAB, PSE, BRO, and COL, respectively. ECO were not recovered from 87.3% of the steaks and when there was recovery, the numbers were mostly ≤ 1 log CFU/100 cm2. Strong correlation was found between the log numbers of AER and PSY, of AER and LAB, and of PSY and LAB, while the correlation between the log numbers of COL and ECO was weak. The numbers of COL and ECO from different groups of steak types or from different cities were not substantially different. Of the four types of steaks, IR had the lowest median values for AER, PSY, LAB, PSE and BRO, followed by CR. The microbiological condition of retail beef steaks in this survey was on par with that in the previous one, with very low numbers of generic E. coli being recovered from very few steaks and the indicators for microbial quality being at numbers much lower than the upper limit for shelf life of beef.


2004 ◽  
Vol 67 (12) ◽  
pp. 2703-2711 ◽  
Author(s):  
KONSTANTINOS P. KOUTSOUMANIS ◽  
LAURA V. ASHTON ◽  
IFIGENIA GEORNARAS ◽  
KEITH E. BELK ◽  
JOHN A. SCANGA ◽  
...  

The survival and growth of Listeria monocytogenes and spoilage microflora during storage of fresh beef subjected to different decontamination treatments was studied. Fresh beef inoculated with a five-strain mixture of L. monocytogenes (5.18 log CFU/cm2) was left untreated (control) or was immersed (30 s) in hot water (HW; 75°C), 2% lactic acid (LA; 55°C), hot water followed by lactic acid (HW-LA), or lactic acid followed by hot water (LA-HW) and then stored aerobically at 4, 10, and 25°C for 25, 17, and 5 days, respectively. Initial populations of L. monocytogenes were reduced by 0.82 (HW), 1.43 (LA), 2.73 (HW-LA), and 2.68 (LA-HW) log CFU/cm2. During storage, the pathogen grew at higher rates in HW than in control samples at all storage temperatures. Acid decontamination treatments (LA, HW-LA, and LA-HW) resulted in a weaker inhibition of L. monocytogenes (P < 0.05) at 25°C than at 4 and 10°C. In general, the order of effectiveness of treatments was HW-LA > LA > LA-HW > HW > control at all storage temperatures tested. In untreated samples, the spoilage microflora was dominated by pseudomonads, while lactic acid bacteria, Enterobacteriaceae, and yeasts remained at lower concentrations during storage. Brochothrix thermosphacta was detected periodically in only a limited number of samples. Although decontamination with HW did not affect the above spoilage microbial profile, acid treatments shifted the predominant microflora in the direction of yeasts and gram-positive bacteria (lactic acid bacteria). Overall, the results of the present study indicate that decontamination with LA and combinations of LA and HW could limit growth of L. monocytogenes and inhibit pseudomonads, which are the main spoilage bacteria of fresh beef stored under aerobic conditions. However, to optimize the efficacy of such treatments, they must be applied in the appropriate sequence and followed by effective temperature control.


2017 ◽  
Vol 6 (1) ◽  
pp. 95
Author(s):  
Karola R. Wendler ◽  
Francis M. Nattress ◽  
Jordan C. Roberts ◽  
Ivy L. Larsen ◽  
Jennifer Aalhus

Packages of moisture-enhanced and conventional pork chops were collected from six Canadian retail stores on five sampling days. The composition of injection brines differed between retailers, but all contained polyphosphates and salt as main ingredients. Meat quality characteristics and bacteriology were analyzed from collected meat samples. Moisture enhanced chops had a higher pH and a higher water holding capacity than conventional. Juiciness and overall tenderness were improved in moisture enhanced chops. The surfaces of moisture enhanced chops were discoloured; the chops were darker and displayed less colour saturation. Total numbers of aerobes, psychrotrophs and lactic acid bacteria were not affected by moisture enhancement but numbers of Enterobacteriaceae, pseudomonads and Brochothrix thermosphacta, bacteria frequently associated with microbial spoilage, were approximately 1 log CFU·g-1 higher in moisture enhanced samples. This work shows moisture enhancement with injection brines containing salt and phosphates can result in a more palatable product. 


2009 ◽  
Vol 27 (Special Issue 1) ◽  
pp. S410-S413 ◽  
Author(s):  
E. Standarová ◽  
I. Borkovcová ◽  
M. Dušková ◽  
H. Přidalová ◽  
M. Dračková ◽  
...  

We evaluated the effect of some factors (batch, producer, storage and amine distribution in cheese) on the biogenic amines and polyamines contents and microbial counts (<I>Enterobacteriaceae</I>, enterococci, lactic acid bacteria) in blue-veined cheese Niva. The tyramine content was increasing (<I>P</I> < 0.01) with storage time; at storage day 29, it reached 298 mg/kg and exceeded the toxicological limit. Cadaverine and the sum of biogenic amines also increased significantly (<I>P</I> < 0.01) and the latter reached up to 900 mg/kg, i.e. the established toxicological limit. The contents of the quantitatively most important biogenic amines (tyramine and cadaverine) and sum of biogenic amines varied according to batch and producer in the ranges of 3.0–337 mg/kg, 3.0–705 mg/kg, and 33–920 mg/kg, respectively. Considerably higher (P</I> < 0.01) contents of tyramine, cadaverine and sum of biogenic amines and higher counts of enterococci and <I>Enterobacteriaceae</I> were found in the edge samples in comparison with the cheese core. The microorganisms were identified as <I>E. faecalis</I> and<I> E. faecium</I>.


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