scholarly journals Microbial Deterioration of Portuguese Lamb Meat as Affected by Its Intrinsic Properties

Proceedings ◽  
2020 ◽  
Vol 70 (1) ◽  
pp. 83
Author(s):  
Gisela Rodrigues ◽  
Sara Coelho-Fernandes ◽  
Ana Sofia Faria ◽  
José M. Lorenzo ◽  
Ursula Gonzales-Barron ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Ash Content ◽  
Meat Production ◽  
Intrinsic Properties ◽  
Psychrotrophic Bacteria ◽  
Lamb Meat ◽  
Spoilage Bacteria ◽  
Spoilage Microorganisms ◽  
Intramuscular Fat Content

In Portugal, the main autochthonous sheep breeds exploited for meat production are Churra Galega Bragançana (CGB) and Bordaleira de Entre Douro e Minho (BEDM). This study aimed to characterise the evolution of spoilage microorganisms in refrigerated vacuum-packed (VP) lamb meat from BEDM and CGB breeds and to elucidate how the intrinsic properties of meat can affect its microbial spoilage. Meat from the BEDM breed presented higher (p < 0.0001) populations of mesophiles, lactic acid bacteria, Pseudomonas spp. and psychrotrophic bacteria, since its higher ultimate pH (means: 5.77 for BEDM vs. 5.58 for CGB) accelerated spoilage rate (p < 0.0001). While water activity and protein content were not found to regulate microbial deterioration (p > 0.05), the growth of spoilage bacteria was exacerbated by higher moisture (p < 0.0001) and higher ash content (p < 0.001). On the contrary, a higher intramuscular fat content slowed down (p < 0.0001) the growth of spoilage bacteria in VP lamb meat.

scholarly journals Effectiveness of Bacteriocin-Producing Lactic Acid Bacteria and Bifidobacterium Isolated from Honeycombs against Spoilage Microorganisms and Pathogens Isolated from Fruits and Vegetables

2020 ◽  
Vol 10 (20) ◽  
pp. 7309
Author(s):  
Chrysa Voidarou ◽  
Athanasios Alexopoulos ◽  
Anastasios Tsinas ◽  
Georgios Rozos ◽  
Athina Tzora ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Antibacterial Activity ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Fruits And Vegetables ◽  
Salmonella Spp ◽  
E Coli ◽  
Hazard Control ◽  
Spoilage Bacteria ◽  
Spoilage Microorganisms

Screening natural products for bacteriocin-producing bacteria may be the equilibrium point between the consumer demand for mild processing and the industry’s need for hazard control. Raw unprocessed honeycombs filled with oregano honey from the alpine mountainous territory of Epirus, Greece were screened for bacteriocinogenic lactic acid bacteria and Bifidobacterium spp., with inhibitory action towards some pathogens and spoilage microorganisms isolated from fresh fruits and vegetables (number and type of strains: three E. coli, two L. monocytogenes, two Salmonella spp., two B.cereus, two Erwinia spp., one Xanthomonas spp., L. innocua (ATCC 33090TM) and E. coli 0157:H7 (ATCC 69373)). Among the 101 collected isolates (73 Lactobacillus, 8 Lactococcus, 8 Leuconostoc and 12 Bifidobacterium species) from the oregano honeycombs (an original finding since there are no other reports on the microbial biodiversity of the flora of the oregano honey), 49 strains of lactic acid bacteria (LAB) and Bifidobacterium spp. were selected and tested for their bacteriocin-producing capacity (34 Lactobacillus, 6 Lactococcus, 5 Leuconostoc and 4 Bifidobacterium). The antibacterial activity exerted by the tested LAB and Bifidobacterium strains was not of the same potency. Our results suggest that the main molecules involved in the antimicrobial activity are probably bacteriocin-like substances (a conclusion based on reduced antibacterial activity after the proteolytic treatment of the cell-free supernatant of the cultures) and this antimicrobial activity is specific for the producing strains as well as for the target strains. The spoilage bacteria as well as the reference microorganisms showed increased resistance to the bacteriocin-like substances in comparison to the wild-type pathogens.

scholarly journals Nisin and ε-poly-L-lysine as natural antimicrobials towards spoilage-associated Lactobacillus plantarum

2021 ◽  
Vol 51 (2) ◽  
Author(s):  
Fernanda Cristina Kandalski Bortolotto ◽  
Maria Helena da Rosa Farfan ◽  
Nathalia Cristina Kleinke Jede ◽  
Gabriela Maia Danielski ◽  
Renata Ernlund Freitas de Macedo
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Inhibitory Concentration ◽  
Inhibitory Effect ◽  
Minimal Bactericidal Concentration ◽  
Natural Antimicrobials ◽  
Food Preservatives ◽  
Spoilage Bacteria ◽  
Mass Spectrometry Identification

ABSTRACT: Sausages are highly susceptible to microbial spoilage. Lactic acid bacteria (LAB) is the main group of spoilage bacteria in vacuum packed cooked sausages. To control microbial growth natural antimicrobials have been used as food preservatives. The aim of this study was to identify strains of lactic acid bacteria isolated from spoiled commercial Calabresa sausages and use them in an in vitro challenge with the natural antimicrobials, nisin (NI) and ε-poly-L-lysine (ε-PL). Mass spectrometry identification of LAB isolated from sausages using MALDI-TOF revealed a predominance of L. plantarum in the LAB population. RAPD-PCR of L. plantarum strains showed four different genetic profiles. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of NI and ε-PL, alone and in combination, against a pool of different profiles L. plantarum were determined. MIC of NI and ε-PL were 0.468 mg/ L and 75 mg/ L; respectively, whereas MBC of NI and ε-PL were 12.48 mg/L and 150 mg/L, respectively. The combined effect of NI and ε-PL was determined using concentrations at 1/4 and 1/8 of individual MICs. Synergistic effect was confirmed at both concentrations showing a fractional inhibitory concentration index of 0.5 and 0.2, respectively. The combination of NI and ε-PL at a small concentration of 0.05 mg/L and 9.375 mg/L, respectively, showed inhibitory effect towards spoilage L. plantarum Results show the potential of the combined use of NI and ε-PL to control sausage spoilage-associated with lactobacilli.

Effect of Single or Sequential Hot Water and Lactic Acid Decontamination Treatments on the Survival and Growth of Listeria monocytogenes and Spoilage Microflora during Aerobic Storage of Fresh Beef at 4, 10, and 25°C

2004 ◽  
Vol 67 (12) ◽  
pp. 2703-2711 ◽  
Author(s):  
KONSTANTINOS P. KOUTSOUMANIS ◽  
LAURA V. ASHTON ◽  
IFIGENIA GEORNARAS ◽  
KEITH E. BELK ◽  
JOHN A. SCANGA ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Listeria Monocytogenes ◽  
Lactic Acid Bacteria ◽  
Hot Water ◽  
Microbial Profile ◽  
Spoilage Bacteria ◽  
Brochothrix Thermosphacta ◽  
Survival And Growth ◽  
Spoilage Microflora ◽  
Storage Temperatures

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 &lt; 0.05) at 25°C than at 4 and 10°C. In general, the order of effectiveness of treatments was HW-LA &gt; LA &gt; LA-HW &gt; HW &gt; 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.

Sodium Lactate Addition on the Quality and Shelf Life of Refrigerated Sliced Poultry Sausage Packaged in Air or Nitrogen Atmosphere

2004 ◽  
Vol 67 (3) ◽  
pp. 601-606 ◽  
Author(s):  
RENATA CEGIELSKA-RADZIEJEWSKA ◽  
JAN PIKUL
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Shelf Life ◽  
Sodium Lactate ◽  
Life Extension ◽  
Poultry Meat ◽  
Color Measurement ◽  
Refrigerated Storage ◽  
Psychrotrophic Bacteria

The aim of this study was to determine the effect of sodium lactate addition on shelf-life extension of sliced poultry sausage packaged both in air and nitrogen atmospheres and stored in refrigerated conditions. Basic chemical composition, pH, and malonaldehyde content were assayed and color measurement using the reflection method was carried out. Microbiological examination consisted of determination of total number of aerobic psychrotrophic bacteria and number of lactic acid bacteria. Sensory evaluation of products was performed. Microbiological and sensory quality of sliced poultry meat sausage was dependent on the addition during production of sodium lactate and the composition of gases (air or nitrogen) used in packaging. Slices of poultry sausage with 1% as well as 2% of sodium lactate maintained their initial quality of evaluated sensory attributes longer, irrespective of the applied gases. Sodium lactate inhibited growth of aerobic psychrotrophic bacteria and lactic acid bacteria during refrigerated storage. Sodium lactate also inhibited the formation of malonaldehyde in sliced poultry sausage during refrigerated storage. The effectiveness of this process depended on the concentration of sodium lactate addition. It was concluded that 1% as well as 2% addition of sodium lactate could extend the shelf life of sliced poultry sausage packaged in air atmosphere and stored at 5 to 7°C by 3 or 4 times, respectively. Sliced poultry sausage treated with 2% sodium lactate packed in nitrogen had the longest (35-day) shelf life. This was a sevenfold increase in the shelf life of sliced poultry sausage compared with the control.

Comparison of the Microflora on Organically and Conventionally Grown Spring Mix from a California Processor

2005 ◽  
Vol 68 (6) ◽  
pp. 1143-1146 ◽  
Author(s):  
CHRISTIE A. PHILLIPS ◽  
MARK A. HARRISON
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Foodborne Pathogens ◽  
Period Analysis ◽  
E Coli ◽  
Psychrotrophic Bacteria ◽  
Microbial Group ◽  
The Mean ◽  
Yeasts And Molds ◽  
Organically Grown

Considerable speculation has occurred concerning the potential for higher numbers of foodborne pathogens on organically grown produce compared with produce not grown organically. The microflora composition of spring mix or mesclun, a mixture of multiple salad ingredients, grown either by organic or conventional means was determined. Unwashed or washed spring mix was obtained from a commercial California fresh-cut produce processor who does not use manure in their cultivation practices. Fifty-four samples of each type of product were supplied over a 4-month period. Analysis included enumeration of total mesophiles, psychrotrophs, coliforms, generic Escherichia coli, lactic acid bacteria, yeasts, and molds. In addition, spring mix was analyzed for the presence of Salmonella and Listeria monocytogenes. The mean populations of mesophilic and psychrotrophic bacteria, yeasts, molds, lactic acid bacteria, and coliforms on conventionally grown spring mix were not statistically different (P &gt; 0.05) from respective mean populations on organically grown spring mix. The mean population of each microbial group was significantly higher on unwashed spring mix compared with the washed product. Of the 14 samples found to contain E. coli, eight were from nonwashed conventional spring mix, one was from washed conventional spring mix, and four were from nonwashed organic spring mix. Salmonella and L. monocytogenes were not detected in any of the samples analyzed.

scholarly journals NIRA LONTAR SEBAGAI KANDIDAT DALAM MEMPERTAHANKAN KANDUNGAN PROTEIN SILASE JEROAN IKAN CAKALANG

2012 ◽  
Vol 8 (3) ◽  
pp. 91
Author(s):  
Yandres Nelson Hege ◽  
I Ketut Suwetja ◽  
Frans G Ijong
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Protein Content ◽  
Acid Content ◽  
Crude Protein ◽  
Crude Protein Content ◽  
Total Acid ◽  
Tuna Fish ◽  
Fermentation Time ◽  
Spoilage Bacteria

Jeroan ikan sebagai limbah dari pengelolaan ikan cakalang panggang di Kupang, Nusa Tenggara Timur dapat dimanfaatkan untuk membuat silase dengan menambahkan bahan nira lontar (Borassus flabellifer) yang telah mengalami fermentasi. Fermentasi dilakukan selama 0–15 hari dan pengujian terhadap total asam, pH, serta kadar protein kasar dilakukan secara teratur. Hasil yang diperoleh menunjukkan bahwa penambahan nira lontar yang telah difermentasi ke dalam jeroan ikan cakalang pada semua konsentrasi secara nyata memberi­kan pengaruh terhadap pertumbuhan bakteri asam laktat dan menekan pertumbuhan bakteri pembusuk, hal ini erat kaitannya dengan kandungan asam (total asam) nira lontar yang berkontribusi terhadap penurunan pH bahan fermentasi. Produk silase jeroan ikan cakalang terbaik, ditinjau dari aspek kadar protein kasar, adalah pada perlakuan konsentrasi nira lontar 10% dengan lama fermentasi 24 jam yang memiliki kandungan protein sebesar 15,46% dari berat basah bahan fermentasi (silase). Kata kunci: Silase, jeroan ikan cakalang, nira lontar, fermentasi   The innards from fresh tuna fish grill in Kupang, Nusa Tenggara Timur can be used to make silage with addition of fermented sap of lontar palm (Borassus flabellifer). Fermentation was carried out for 0–15 days and regularly tested for total acid, pH, as well as the crude protein content. The results showed that the addition of palm sap that has been fermented into the innards of tuna at all concentrations significantly impact the growth of lactic acid bacteria and suppress the growth of spoilage bacteria, it is closely related to the acid content (total acid) that contribute to the palm sap decrease in pH of fermentation ingredients. Tuna offal silage products best viewed from the aspect of the content of crude protein in the treatment of palm sap concentration of 10% with a 24-hour fermentation time which has a protein content of 15.46% by weight of the wet ingredients fermentation (silage). Keywords: Silage, tuna offal, lontar palm sap, fermentation

Growth Rates of Mesophilic Bacteria, Aerobic Psychrotrophic Bacteria, and Lactic Acid Bacteria in Low-Dose–Irradiated Pork

1999 ◽  
Vol 62 (11) ◽  
pp. 1297-1302 ◽  
Author(s):  
RAVEENDRAN J. VENUGOPAL ◽  
JAMES S. DICKSON
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Bacterial Population ◽  
Vacuum Packaging ◽  
Lag Phase ◽  
Phase Duration ◽  
Psychrotrophic Bacteria ◽  
Gompertz Equation ◽  
Pork Patties ◽  
Descriptive Models

Frozen pork patties, thawed overnight at 0°C or temperature abused through storage at 15°C for 24 h, were packaged using both vacuum and air packaging methods. Immediately after packaging, both sets of patties were irradiated at 0, 0.5, 1, and 2 kGy. All the samples were stored at 2°C and were analyzed for populations of mesophilic, psychrotrophic, and lactic acid bacteria every 3 days for 30 days. By using a mesophilic population of 107 cells/g as a criteria for spoilage, fresh pork patties receiving a dose of 0 kGy had shelf lives of 11 and 16 days with air and vacuum packaging methods, respectively, whereas temperature-abused patties had a shelf life of 7 days with both air and vacuum packaging methods. Both fresh and abused patties that received a dose of 2 kGy had shelf lives that were greater than 30 days at 2°C with both air and vacuum packaging methods. Descriptive models based on the Gompertz equation for mesophilic, psychrotrophic, and lactic acid bacteria were developed, and the generation time and lag-phase duration for each bacterial population were calculated.

Sign in / Sign up

Export Citation Format

Share Document