Effect of glucose, pH and lactic acid on Carnobacterium maltaromaticum, Brochothrix thermosphacta and Serratia liquefaciens within a commercial heat-shrunk vacuum-package film

2020 ◽  
Vol 91 ◽  
pp. 103515
Author(s):  
Kaniz Mohsina ◽  
David A. Ratkowsky ◽  
John P. Bowman ◽  
Shane Powell ◽  
Mandeep Kaur ◽  
...  
1983 ◽  
Vol 46 (12) ◽  
pp. 1078-1083 ◽  
Author(s):  
H.-J.S. NIELSEN ◽  
P. ZEUTHEN

Studies were done on the influence of phosphate and glucose addition on some selected spoilage bacteria in vacuum packed sliced bologna-type sausage during refrigerated storage. Batches with low pH phosphate mixture or sodium tripolyphosphate were used along with batches without phosphate addition. Addition of low pH phosphate had a pronounced influence on Brochothrix thermosphacta and Serratia liquefaciens, while the influence of glucose addition on these bacteria was small. No marked effect of phosphate type could be observed with the lactic acid bacteria, but the most profound growth happened in sausages without phosphate, and at 2°C was stimulated by glucose addition. Lactic acid accumulated more rapidly in batches without phosphate addition.


1983 ◽  
Vol 46 (3) ◽  
pp. 216-221 ◽  
Author(s):  
M. O. HANNA ◽  
J. W. SAVELL ◽  
G. C. SMITH ◽  
D. E. PURSER ◽  
F. A. GARDNER ◽  
...  

Large increases in counts cf Leuconostoc spp., Lactobacillus coryneformis, Lactobacillus plantarum, Lactobacillus viridescens and Lactobacillus curvatus occurred over a 28-d display period when aseptically fabricated steaks were inoculated with 103 to 104 cells/cm2 of these species and then were vacuum-packaged. With Lactobacillus cellobiosus 2, Serratia liquefaciens or Hafnia alvei as inoculum, increases in count were much smaller. Counts of L. cellobiosus 1, Brochothrix thermosphacta, a Moraxella sp. and Alteromonas putrefaciens of inoculated steaks decreased during display. With a higher inoculum (106 cells/cm2), increases in counts of lactic acid bacteria usually were smaller. Some lactic acid bacteria caused marked decreases (0.2 to 0.5) in the pH of the meat surface. Changes in surface discoloration of uninoculated and inoculated steaks over a 28-d display period were not significant (P>0.05). Off-odor scores of both uninoculated and inoculated steaks were lower (more off-odor) after display but few of the differences were significant. Off-odors of steaks inoculated with lactic acid bacteria were described as “sour”, “buttermilk”, “sulfur-like” and “H2S”.


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. 


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.


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