References of "Clinquart, Antoine"
     in
Bookmark and Share    
Full Text
See detailCarnobacterium maltaromaticum isolated from vacuum-packed beef with long shelf life: morphological and functional characterization
Didimo Imazaki, Pedro Henrique ULg; Tahiri, Assia ULg; Ndedi Ekolo, François et al

Poster (2014, September)

This study was conducted as part of a research project on meat conservability, in particular vacuum packaged beef displaying very long shelf lives at a temperature close to the freezing point, and its ... [more ▼]

This study was conducted as part of a research project on meat conservability, in particular vacuum packaged beef displaying very long shelf lives at a temperature close to the freezing point, and its objective was to perform a morphological and functional characterization of C. maltaromaticum with potential bioprotective effect isolated from vacuum packaged long shelf life beef. The isolated C. maltaromaticum strain presented similar morphological, biochemical and enzymatic profiles as those of two reference strains (LMG 11393 and LMG 22902). Among the studied conditions, a temperature of +12 °C and an atmosphere poor in oxygen (100 % N2) were the optimal conditions for the growth of C. maltaromaticum. Nevertheless, growth on lower temperatures is also possible. After inoculation of beef samples with C. maltaromaticum and 7 days of storage under vacuum at −1 °C, no effect was observed on the total viable count and on the count of lactic acid bacteria. A reduction of Pseudomonas sp. and Brochothrix thermosphacta was observed during the first week of storage under vacuum conditions. After 7 days of subsequent storage of the same samples under modified atmosphere at +4 °C, the inoculant favored the growth of B. thermosphacta and inhibited the growth of Enterobacteriaceae under 100 % N2. No effect of the inoculant was observed when an atmosphere rich in oxygen was applied. The evaluation of the influence of different atmospheres showed that the growth of C. maltaromaticum was slower in an atmosphere containing O2 and CO2. Long-term storage under vacuum at low temperatures are therefore suitable for the growth of this bacterium. An antimicrobial effect against Enterobacteriaceae was highlighted on inoculated fresh meat stored under N2. The functional characterization of this strain will be further pursued by genotypic characterization. Special attention will be taken to study its bioprotective properties. [less ▲]

Detailed reference viewed: 13 (0 ULg)
Full Text
See detailMorphological and functional characterization of Carnobacterium maltaromaticum isolated from vacuum-packed beef with long shelf life
Didimo Imazaki, Pedro Henrique ULg; Tahiri, Assia ULg; Ndedi Ekolo, François et al

Poster (2014, August)

The aim of this study was to perform a morphological and functional characterization of a Carnobacterium maltaromaticum strain with a potential bioprotective effect isolated from vacuum packaged long ... [more ▼]

The aim of this study was to perform a morphological and functional characterization of a Carnobacterium maltaromaticum strain with a potential bioprotective effect isolated from vacuum packaged long shelf life beef. The morphological, biochemical and enzymatic profiles, the influence of different temperatures and atmospheres, and the microbial stability of fresh beef inoculated with the C. maltaromaticum strain were evaluated. The isolated C. maltaromaticum strain presented similar morphological, biochemical and enzymatic profiles as those of two reference strains (LMG 11393 and LMG 22902). The growth of C. maltaromaticum was slower in an atmosphere containing O2 and CO2. Vacuum packing is therefore suitable for this bacterium. An antimicrobial effect against Enterobacteriaceae was highlighted on inoculated fresh meat stored under N2. The functional characterization of this isolate will be further pursued by a genotypic characterization to better understand its potential bioprotective effect. [less ▲]

Detailed reference viewed: 9 (0 ULg)
Full Text
See detailInfluence of aging technique and muscle on physicochemical stability and antioxidant capacity of high-oxygen atmosphere packed beef
Didimo Imazaki, Pedro Henrique ULg; Tahiri, Assia ULg; Thimister, Jacqueline ULg et al

Poster (2014, August)

The aim of this study was to compare the effect of aging technique (wet-aging vs. carcass-aging), muscle (longissimus dorsi vs. rectus femoris) and previous vacuum storage time on color and lipid ... [more ▼]

The aim of this study was to compare the effect of aging technique (wet-aging vs. carcass-aging), muscle (longissimus dorsi vs. rectus femoris) and previous vacuum storage time on color and lipid stability of beef packaged in high-oxygen atmosphere. After a seven-day wet- or carcass-aging step, longissimus dorsi and rectus femoris muscle cuts from 4 Belgian Blue cows were vacuum packaged and stored at −1 °C for up to 28 days. At different times, part of these samples was repackaged under modified atmosphere – 70 % O2:30 % CO2 –, and stored during 7 days at +4 °C. The following parameters were evaluated at different intervals: color (CIE L*a*b*), metmyoglobin %, lipid oxidation (TBARS), antioxidant enzyme activities (catalase, glutathione peroxidase and superoxide dismutase), alpha-tocopherol and fat content. The sensitivity of modified atmosphere repacked meat cuts to oxidation was influenced by the conditions of the previous aging period (wet > carcass conditions), muscle (rectus femoris > longissimus dorsi) and length of the vacuum storage. Oxidation stability could be associated with catalase activity, and no association could be established with the alpha-tocopherol content. [less ▲]

Detailed reference viewed: 13 (0 ULg)
Full Text
Peer Reviewed
See detailEvaluation of the bacterial diversity and its evolution during storage of fresh beef from British and Belgian origins under different atmosphere and temperature conditions
Didimo Imazaki, Pedro Henrique ULg; Tahiri, Assia ULg; Taminiau, Bernard ULg et al

Conference (2013, December 10)

The purpose of this study was to evaluate the bacterial diversity and its evolution during storage of fresh beef, depending on its origin, packaging and storage temperature, by using a metagenomic ... [more ▼]

The purpose of this study was to evaluate the bacterial diversity and its evolution during storage of fresh beef, depending on its origin, packaging and storage temperature, by using a metagenomic approach. Metagenomic analyzes revealed that the origin, atmosphere and temperature conditions influenced the selection of the predominant flora. Vacuum-packaged British samples presented higher concentrations of Lactobacillus algidus at the begging of the experiment than Belgian samples. Furthermore, the development of Lactobacillus algidus was favored in British and Belgian samples preserved under vacuum at −1 °C, while a predominance of Lactococcus piscium was observed for samples stored at +4 °C. These microorganisms have already been isolated from beef, but taking into account that the knowledge about these two species is currently limited, it is still not possible to state if the conservability of the tested samples was influenced by the presence of these bacteria. Moreover, storage under modified atmosphere favored the development of Leuconostoc gasicomitatum in both British and Belgian samples. This specie is often associated with spoilage of cold-stored modified-atmosphere-packaged (MAP) nutrient-rich foods. This result can partially explain the short shelf-life of the samples once they are stored under this condition. Metagenomics showed to be a useful tool to study the microbial population of a complex matrix since some of the identified genera could not have grown or have grown slowly in culture media commonly used. In addition, it helped to clarify the evolution of the bacterial ecosystem associated to meat during its storage. [less ▲]

Detailed reference viewed: 50 (12 ULg)
Full Text
Peer Reviewed
See detailInfluence of two breeds (Belgian Blue and Limousin) and previous storage time on pigment and lipid stability of high-oxygen atmosphere packaged beef
Didimo Imazaki, Pedro Henrique ULg; Tahiri, Assia ULg; Thimister, Jacqueline ULg et al

Poster (2013, December 10)

The aim of this study was to evaluate the effect of two breeds (Belgian Blue vs. Limousin) and previous storage time in vacuum conditions on color and lipid stability of meat packaged in high-oxygen ... [more ▼]

The aim of this study was to evaluate the effect of two breeds (Belgian Blue vs. Limousin) and previous storage time in vacuum conditions on color and lipid stability of meat packaged in high-oxygen atmosphere. Limousin meat samples of this study presented a higher sensitivity to myoglobin and lipid oxidation than Belgian Blue samples. The higher content of fat in those samples was one of the factors that could explain this higher sensitivity. Lipid oxidation and myoglobin oxidation appear to be linked, and further studies to understand the interaction between both processes are still needed. An understanding of the oxidative processes and their interaction would provide a basis for explaining quality deterioration in meat and also for developing strategies (e.g. antioxidant supplementation) to maintain sensory qualities. [less ▲]

Detailed reference viewed: 40 (8 ULg)
Full Text
Peer Reviewed
See detailBacterial diversity and its evolution during storage of fresh beef from different origins under different atmosphere and temperature conditions
Didimo Imazaki, Pedro Henrique ULg; Tahiri, Assia ULg; Taminiau, Bernard ULg et al

Poster (2013, October 11)

The purpose of this study was to evaluate the bacterial diversity and its evolution during storage of fresh beef, depending on its origin, packaging and storage temperature. Two batches of three vacuum ... [more ▼]

The purpose of this study was to evaluate the bacterial diversity and its evolution during storage of fresh beef, depending on its origin, packaging and storage temperature. Two batches of three vacuum packed striploins from United Kingdom and Belgium were obtained from a food wholesaler located in the Walloon Region. Fifteen days after slaughter, the striploins were sliced and individually kept under vacuum for 30 days: i) at −1 °C; ii) at +4 °C and iii) at −1 °C for 15 days and then at +4 °C for 15 days. The bacterial diversity was evaluated by metagenomic approach 15, 30 and 45 days after slaughter. Furthermore, each 15 days part of the vacuum packed striploin slices were repacked under modified atmosphere (70 % O2/30 % CO2), stored at +4 °C for 2 days and at +8 °C for 5 days, and then analyzed. Metagenomic analysis revealed a selection of the initial flora depending on atmosphere and temperature conditions. The development of Lactobacillus algidus was favored in samples preserved under vacuum at −1 °C, while a predominance of Lactococcus piscium was observed for samples stored at +4 °C. Moreover, storage under modified atmosphere favored the development of Leuconostoc gasicomitatum. These microorganisms have already been isolated from beef, but no study has evaluated their role in food conservation. The next step of this study will be to isolate and characterize strains of Lactobacillus algidus from meat and to assess their bioprotective potential. [less ▲]

Detailed reference viewed: 32 (9 ULg)
Full Text
See detailGrowth performance and meat quality of stress negative Piétrain pigs in the tropics: the case of Vietnam
Ha Xuan, Bo; Do Duc, Luc ULg; Moula, Nassim ULg et al

Poster (2013, October 11)

This study was carried out at the animal farm of Hanoi University of Agriculture, Vietnam to evaluate the growth performance and meat quality of stress negative Piétrain pigs. The study concerns the body ... [more ▼]

This study was carried out at the animal farm of Hanoi University of Agriculture, Vietnam to evaluate the growth performance and meat quality of stress negative Piétrain pigs. The study concerns the body weight (BW) of 116 pigs at 7.5 months of age and the ultrasound measurements on 83 live animals in order to determine backfat thickness, longissimus muscle depth and lean meat percentage (LM). Meat color (C.I.E L*, a* and b*), peak shear force (SF), pH at 24h (pH24) and at 45 minutes (pH45) post mortem were measured on 31 meat samples. Meat chemical composition (dry matter, protein, lipids and ash) was determined on 23 meat samples. All the data were analyzed according to a linear fixed model including gender effect (female and intact males) and Halothane genotype (CC and CT). The interaction between gender and genotype was not observed and therefore it was ignored from the final model. The results show that BW and LM were not significantly different between genotypes (P>0.21) while females were heavier than males (101.11 vs. 93.85 kg, P=0.0011). LM of female and male were respectively 63.27 and 63.56%. Gender and genotype didn’t affect meat quality and chemical composition (P>0.05) except pH24 (P=0.0011), a* (P<0.0001) and lipids (P=0.0012) for gender effect. The pH45 (6.50 and 6.45 for females and males) and pH24 (5.34 and 5.49 for females and males) were in the range corresponding to a normal meat. The obtained results show that stress negative Piétrain pigs have high lean meat percentage and satisfactory meat quality under tropical climatic conditions in Vietnam. [less ▲]

Detailed reference viewed: 27 (8 ULg)
Full Text
Peer Reviewed
See detailInfluence of breed and previous storage time on color and lipid stability of beef packaged in high-oxygen atmosphere
Didimo Imazaki, Pedro Henrique ULg; Tahiri, Assia ULg; Thimister, Jacqueline ULg et al

Poster (2013, August 20)

The aim of this study was to compare the effect of two breeds (Belgian Blue vs. Limousin) and previous vacuum storage time on color and lipid stability of meat packaged in high-oxygen atmosphere. Vacuum ... [more ▼]

The aim of this study was to compare the effect of two breeds (Belgian Blue vs. Limousin) and previous vacuum storage time on color and lipid stability of meat packaged in high-oxygen atmosphere. Vacuum packaged striploins from Belgian Blue and Limousin cows were stored at −1 °C and +4 °C for up to 60 days and analyzed. Part of these samples were repackaged under modified atmosphere – 70 % O2/30 % CO2 – at different times, stored 2 days at +4 °C and 5 d at +8 °C, and then analyzed. The following parameters were evaluated: color (CIE L*a*b*), metmyoglobin %, lipid oxidation (TBARS) and fat content. Color measurement and metmyoglobin % determination showed greater pigment stability in Belgian Blue samples than in Limousin. Belgian Blue also presented higher lipid stability (TBARS). A positive correlation between pigment oxidation and lipid oxidation was highlighted. The greater amount of fat in meat of Limousin could partially explain its higher sensitivity to oxidation. Nevertheless, other factors may be involved in oxidative stability such as metmyoglobin reducing activity and antioxidant capacity. An understanding of the oxidative processes and their interaction would provide a basis for explaining quality deterioration in meat and for developing strategies to maintain sensory qualities. [less ▲]

Detailed reference viewed: 38 (8 ULg)
Full Text
Peer Reviewed
See detailMuscle Characteristics, Meat Tenderness and Nutritional Qualities Traits of Borgou, Lagunaire and Zebu Fulani Bulls Raised on Natural Pasture in Benin
Salifou, C.F.A.; Dahouda, Mahamadou; Houaga, I et al

in International Journal of Animal and Veterinary Advances (2013), 5(4), 143-155

This study was carried out to evaluate muscle characteristics, meat ten derness and nutritional qualities of Benin indigenous cattle raised on natural pasture. Thus, 10 Zebu Fulani, 10 Borgou and 5 ... [more ▼]

This study was carried out to evaluate muscle characteristics, meat ten derness and nutritional qualities of Benin indigenous cattle raised on natural pasture. Thus, 10 Zebu Fulani, 10 Borgou and 5 Lagunaire were slaughtered at 5 years old and their Longissimus thoracis muscle samples were collected for analyses. Lactate dehydrogenase activity of Zebu Fulani was higher (p<0.05) than that of Lagunaire (3494 vs 2813 μmol/min/g protein) while that of Borgou was not significantly different from those of the two other breeds (p>0.05). As for isocitrate dehydrogenase, citrate synthase, cytochrome oxidase and phosphofructokinase, no significant difference was observed between the three breeds (p>0.05). By contrast, the total collagen content of Borgou (5.2 mg OH-proline/mg dry matter) was higher (p<0.01) than those of Zebu Fulani (3.1 mg OH-proline/mg dry matter) and Lagunaire (3.2 mg OH-proline/mg dry matter). The myosin heavy chain isoforms I, IIa and IIx were not different between the three breeds. The dry matter, the crude protein and the ether extract percentage were not significantly varied from one breed to another. Branched-chain Fatty Acids and saturated fatty acids contents were identical in Lagunaire and Borgou (p>0.05) while the Zebu Fulani had the highest values (p<0.05). The ratio n-6 to n-3 fatty acids obtained in the Zebu was the lower. In general, according to the fatty acids profile, Borgou and Lagunaire bulls’ meat is better than that of Zebu for heart disease [less ▲]

Detailed reference viewed: 17 (1 ULg)
Full Text
Peer Reviewed
See detailUtilization of Large White x Mong Cai crossbred sows, Duroc and stress negative Piétrain boars for the production of fattening pigs under household conditions in northern Vietnam
Do Duc, Luc ULg; Clinquart, Antoine ULg; Vu Dinh, Ton et al

in Animal Production Science (2013)

The objective of the present study was to compare Duroc (DU) and stress-negative Piétrain (PI) as terminal sires mated to F1(Large White x Mong Cai) sows (F1) on productivity, carcass characteristics ... [more ▼]

The objective of the present study was to compare Duroc (DU) and stress-negative Piétrain (PI) as terminal sires mated to F1(Large White x Mong Cai) sows (F1) on productivity, carcass characteristics, meat quality and meat chemical composition under household conditions in Hai Duong province, Vietnam. The reproduction performances were based on 74 litters of 42 F1 sows from 12 households and the semen from 11 Duroc and 10 Piétrain boars. Data on production and carcass traits were collected from 76 DUxF1and 67 PIxF1 crossbred fattening pigs. Longissimus dorsi samples from 55 and 37 of DUxF1 and PIxF1 respectively were analyzed to determine meat quality and meat chemical composition. The results show that household affected production, carcass, and meat quality traits (P<0.05) as well as reproduction (weights at birth and weaning, P<0.01). Inversely, boar breeds did not influence (P>0.06) on reproduction traits (except individual weight of born alive pigs and weaned pigs, P<0.01), production traits, meat chemical composition and meat quality (except pH at 4 days post mortem, P<0.05) while lean meat percentage of Piétrain-sired pigs was higher than those of Duroc-sired pigs (P<0.05). The utilization of Piétrain boars does not affect reproduction performances, growth rate and meat quality while improving lean meat percentage in comparison to Duroc boars. This suggests that the use of stress-negative Piétrain boars as terminal sires would improve lean meat percentage under household conditions in North Vietnam. [less ▲]

Detailed reference viewed: 54 (26 ULg)
Full Text
Peer Reviewed
See detailRetrospective Analysis of a Listeria monocytogenes Contamination Episode in Raw Milk Goat Cheese Using Quantitative Microbial Risk Assessment tools
Delhalle, Laurent ULg; Ellouze, Mariem; Yde, Marc et al

in Journal of Food Protection (2012), 75(12), 2122-2135

In 2005, the Belgian authorities reported a Listeria monocytogenes contamination episode in cheese made from raw goat's milk. The presence of an asymptomatic shedder goat in the herd caused this ... [more ▼]

In 2005, the Belgian authorities reported a Listeria monocytogenes contamination episode in cheese made from raw goat's milk. The presence of an asymptomatic shedder goat in the herd caused this contamination. On the basis of data collected at the time of the episode, a retrospective study was performed using an exposure assessment model covering the production chain from the milking of goats up to delivery of cheese to the market. Predictive microbiology models were used to simulate the growth of L. monocytogenes during the cheese process in relation with temperature, pH, and water activity. The model showed significant growth of L. monocytogenes during chilling and storage of the milk collected the day before the cheese production (median increase of 2.2 log CFU/ml) and during the addition of starter and rennet to milk (median increase of 1.2 log CFU/ml). The L. <br /><br />monocytogenes concentration in the fresh unripened cheese was estimated to be 3.8 log CFU/g (median). This result is consistent with the number of L. monocytogenes in the fresh cheese (3.6 log CFU/g) reported during the cheese contamination episode. A variance-based method sensitivity analysis identified the most important factors impacting the cheese contamination, <br /><br />and a scenario analysis then evaluated several options for risk mitigation. Thus, by using quantitative microbial risk assessment tools, this study provides reliable information to identify and control critical steps in a local production chain of cheese made from raw goat's milk. [less ▲]

Detailed reference viewed: 156 (15 ULg)
Full Text
Peer Reviewed
See detailLa diversité bactérienne et son évolution pendant la conservation de viandes bovines fraîches de différentes origines conditionnées sous vide
Didimo Imazaki, Pedro Henrique ULg; Tahiri, Assia ULg; Taminiau, Bernard ULg et al

Poster (2012, December)

Le but de cette étude à été d'évaluer la diversité bactérienne et son évolution pendant la conservation de viandes bovine fraîches sous vide, en fonction de leur origine et du respect ou non d’une ... [more ▼]

Le but de cette étude à été d'évaluer la diversité bactérienne et son évolution pendant la conservation de viandes bovine fraîches sous vide, en fonction de leur origine et du respect ou non d’une température proche du point de congélation. Les dénombrements réalisés ont mis en évidence que les viandes d’origines britannique et belge testées présentent un écosystème microbien différent. Les analyses par approche métagénomique permettront d’éclaircir ces différences, surtout en ce qui concerne la présence de bactéries pouvant jouer un rôle "bioprotecteur" permettant d’améliorer la conservabilité des viandes. [less ▲]

Detailed reference viewed: 74 (10 ULg)
Full Text
Peer Reviewed
See detailValidation de la qualité de la viande hachée de porc par une approche métagénomique ciblée
Taminiau, Bernard ULg; Nezer, Carine; Adolphe, Ysabelle ULg et al

Conference (2012, November 13)

Food products represent great biotopes for bacteria. The optimization of foodstuffs conservation pass by a better understanding of those biotopes and their spoilage. The current techniques of new ... [more ▼]

Food products represent great biotopes for bacteria. The optimization of foodstuffs conservation pass by a better understanding of those biotopes and their spoilage. The current techniques of new generation sequencing give a new dimension to the microbial ecology, through the metagenomic analysis of individuals' large number, within a mixed microbial population. Our aim is to demonstrate that this methodology can be successfully applied to the validation of the quality of foodstuffs during storage. This study was carried out on pork minced meat with shelf-life tests in various conditions of preservation (temperature and packaging). The analysis was performed in parallel with standardized microbiological methods and with massive sequencing of two hypervariables regions of the rDNA 16S. The results show an excellent correlation between the two approaches and underline the tremendous utility of metagenomic analysis for in-depth characterization of the potential altering bacteria in fresh meat. [less ▲]

Detailed reference viewed: 80 (10 ULg)
Full Text
Peer Reviewed
See detailViandes bovines à longue durée de conservation conditionnées sous vide : isolement et caractérisation de souches de Carnobacterium
Didimo Imazaki, Pedro Henrique ULg; Tahiri, Assia ULg; Baptista Rodrigues, Ana Lucia ULg et al

Poster (2012, November 13)

The lactic acid bacteria Carnobacterium divergens and Carnobacterium maltaromaticum are often associated to meat and meat products and may be used as a protective culture, improving the microbial ... [more ▼]

The lactic acid bacteria Carnobacterium divergens and Carnobacterium maltaromaticum are often associated to meat and meat products and may be used as a protective culture, improving the microbial stability and the safety of these products. In this context, the aim of this study was to isolate and characterize Carnobacterium from long shelf-life vacuum-packed beef. LAB counts after culture at +22°C remained below 2.0 log UFC/cm², even at the end of shelf life. On the other hand, the ecosystem evaluation performed by metagenomics revealed the predominance of Carnobacterium and Lactobacillus on the samples. After spreading of a peptone water suspension obtained from the samples on PCA, pure isolates were collected and identified by API 50 CHL galleries. Seventy-eight % of isolates were C. maltaromaticum, 3 % C. divergens and 19 % could not be identified. The next step of this work will consist in performing a genotypic and functional characterization of these Carnobacterium isolates. [less ▲]

Detailed reference viewed: 92 (23 ULg)
Full Text
Peer Reviewed
See detailValidation of a method for measuring the colour and determining the proportions of myoglobin redox forms on beef
Didimo Imazaki, Pedro Henrique ULg; Salmon, Olivier; Tahiri, Assia ULg et al

Poster (2012, October 19)

The aim of this study was to validate the use of the spectrophotometer Minolta CM-600d for measuring the colour and the proportions of different myoglobin redox forms (oxymyoglobin, deoxymyoglobin, and ... [more ▼]

The aim of this study was to validate the use of the spectrophotometer Minolta CM-600d for measuring the colour and the proportions of different myoglobin redox forms (oxymyoglobin, deoxymyoglobin, and metmyoglobin) on the surface of meat. One vacuum-packaged (VP) striploin was supplied by a Belgian food wholesaler. It was cut in 3 cm thick steaks, repacked under vacuum and stored at −0.5 °C until analyses. The measurement of colour in the C.I.E. L*a*b* space and the determination of oxymyoglobin, deoxymyoglobin, and metmyoglobin were performed on VP and modified atmosphere-packed (70 % O2/30 % CO2 for 24 h) samples (n = 10). Results obtained were compared to two reference methods (colour measurement using a chromameter Minolta CR-400 and spectrophotometric determination of different myoglobin redox forms in aqueous meat extracts) by F-test for precision and t-test for accuracy. Statistic significance level was established at 5 %. The two colour measurement methods presented the same precision, when considering VP samples only, and different accuracies, probably because of the different detectors and observation angles used by both devices. The two methods for determining the different myoglobin forms presented also the same precision but different accuracies, probably due to the fact that oxygenation is favoured during some steps of the reference method (e.g. extraction, filtration). In conclusion, the results for colour measurement obtained by both devices cannot be compared. It is necessary to compare both methods for determining oxymyoglobin, deoxymyoglobin, and metmyoglobin in complete anaerobic conditions in order to eliminate the oxygenation bias. [less ▲]

Detailed reference viewed: 48 (16 ULg)
Full Text
See detailL’analyse métagénomique ciblée au service de la microbiologie des aliments : applications concrètes
Taminiau, Bernard ULg; Nezer, Carine; Delhalle, Laurent ULg et al

Conference (2012, September 21)

Detailed reference viewed: 110 (23 ULg)
Full Text
Peer Reviewed
See detailEffect of duration and temperature of previous vacuum-packed storage on the microbiological quality of Belgian Blue meat packed in high-oxygen atmosphere
Didimo Imazaki, Pedro Henrique ULg; Tahiri, Assia ULg; Daube, Georges ULg et al

Poster (2012, September 05)

The aim of this experiment was to study the effect of duration and temperature of previous vacuum-packed (VP) storage on the microbiological quality of Belgian Blue (BB) beef packed in high-oxygen ... [more ▼]

The aim of this experiment was to study the effect of duration and temperature of previous vacuum-packed (VP) storage on the microbiological quality of Belgian Blue (BB) beef packed in high-oxygen atmosphere. VP striploins from bulls (B) and cows (C) were stored at −1 °C and +4 °C for up to 80 days. These meats were subsequently repackaged under modified atmosphere (MA) – 70 % O2/30 % CO2 – at different times, and stored 2 d at +4 °C and 5 d at +8 °C. The average initial counts in VP meats were 3.6 log CFU/cm² (B) and 2.7 log CFU/cm² (C) for total viable count (TVC) at +22 °C; < 2.0 log CFU/cm² (B and C) for lactic ac id bacteria (LAB) at +22 °C; 1.1 log CFU/cm² (B) and 1.3 log CFU/cm² (C) for Enterobacteriaceae at +30 °C and < 1.0 log CFU/cm² (B and C) for Pseudomonas spp. and Brochothrix thermosphacta. During the first 40 days of VP storage, temperature had a striking influence on microbial growth. The maximum count differences between storage temperatures were obtained at the 20th day of storage: 2.7 log CFU/cm² (B) and 2.9 log CFU/cm² (C) for TVC, 4.0 log CFU/cm² (B and C) for LAB and 3.6 log CFU/cm² (B and C) for Enterobacteriaceae. The difference in TVC between temperatures at the 20th day tended to disappear once the meats were repacked under MA and stored during seven days. Conversely, the difference in LAB and Enterobacteriaceae counts tended to be maintained after MA repackaging, showing that duration and temperature of VP storage had influence on microbiological quality of BB meat subsequently stored in high-oxygen atmosphere. Moreover, chilling at temperatures very close to the freezing point of meat during VP storage, which has already showed innumerous advantages for physicochemical quality of meat, was capital to maintain the microbiological quality of BB fresh meat during subsequent MA-packed storage. [less ▲]

Detailed reference viewed: 65 (12 ULg)
Full Text
See detailMetagenomic analysis as a tool to better characterize the bacterial content of food and food preparations.
Taminiau, Bernard ULg; Delhalle, Laurent ULg; Nezer, Carine et al

Conference (2012, September 04)

Metagenomic analysis is a new culture-independent approach for assigning a taxonomic, genic or functional identity to bacterial DNA fragments of unknown origin. Its power and utility is increasingly ... [more ▼]

Metagenomic analysis is a new culture-independent approach for assigning a taxonomic, genic or functional identity to bacterial DNA fragments of unknown origin. Its power and utility is increasingly rising thanks to the next generation sequencing techniques. It is now mature and cheap enough to be transposed to more applied fields like the food microbiology. We demonstrated in several studies the extraordinary potential of the targeted metagenomic analysis to different problematics related to food products. First, this approach is highly useful for the validation of the shelf life of food products. We analyzed standardized pork minced meat and meat product samples packaged either under modified atmosphere (MAP - 30% CO2, 70% O2) or under permeable atmosphere packaging, stored at different temperature (4°C, 4-8°C and 12°C) until the end of shelf-life. The metagenomic analysis allowed to identify species of all the sub-dominant bacterial populations. This approach showed why MAP can improve meat quality by favoring certain species rather than others. As a second example, we sought to identify the potential spoiling bacteria in several food products like raw fish, rind cheese or vacuum packed beef meats in order to illustrate the usefulness of metagenomics for the quality control of food preparations. Samples from various food matrices were screened to identify the bacterial contaminants. We combined the bioinformatics analysis with a classical approach to generate effective quantitative data for the various bacterial populations detected. This analysis characterizes the samples both on the identity of the potential spoiling bacteria present and on the quantification level of the contaminants. Finally, the metagenomic analysis reveals the presence of numerous uncultured and uncharacterized bacteria. The use of a carefully designed analysis pipeline has been used to ensure to label the bacterial population with a precise taxonomic identity and to determine whether the targeted population corresponds to a known species or not. This way, even if the nearest known homologous sequence is an environmental sample, its relatedness to known species can be deduced. This represents a new tool to trace yet uncharacterized food spoiling bacteria. [less ▲]

Detailed reference viewed: 84 (11 ULg)
Full Text
Peer Reviewed
See detailLes modèles de microbiologie prévisionellepour la maitrise de la sécurité des aliments (synthèse bibliographique)
Delhalle, Laurent ULg; Daube, Georges ULg; Adolphe, Ysabelle ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2012), 16(3), 369-381

Predictive microbiology aims to predict the evolution of microorganisms in foods with mathematical models. Several models have been published and the complexity of some of them makes their use difficult ... [more ▼]

Predictive microbiology aims to predict the evolution of microorganisms in foods with mathematical models. Several models have been published and the complexity of some of them makes their use difficult for the uninitiated. However, the use of this discipline will become widespread in coming years. These models provide, for example, additional tools to ensure the microbiological safety of food, to establish the contamination flow in a food chain, to develop and to assist the quality assurance systems. The development of new computer software and database will enable stakeholders in the food chain to have a better control of microbiological hazards. The aim of this summary is to give an overview of existing models of predictive microbiology and their applications. A first approach of the primary, secondary and tertiary models is given. The modelling of latency, integrated models and growth tests are also discussed. [less ▲]

Detailed reference viewed: 129 (20 ULg)
Full Text
Peer Reviewed
See detailEffect of duration and temperature of previous vacuum-packed storage on the oxidative stability of Belgian Blue meat packed in high-oxygen atmosphere
Didimo Imazaki, Pedro Henrique ULg; Tahiri, Assia ULg; Thimister, Jacqueline ULg et al

Poster (2012, August 13)

The aim of this experiment was to study the effect of duration and temperature of previous vacuum-packed (VP) storage on the oxidative stability of Belgian Blue meat packed in high-oxygen atmosphere. VP ... [more ▼]

The aim of this experiment was to study the effect of duration and temperature of previous vacuum-packed (VP) storage on the oxidative stability of Belgian Blue meat packed in high-oxygen atmosphere. VP striploins from bulls and cows were stored at −1 °C and +4 °C for up to 80 days and analyzed. These same meat samples were also repackaged under modified atmosphere (MA) – 70 % O2/30 % CO2 – at different times, stored 2 d at +4 °C and 5 d at +8 °C, and then analyzed. Meat from cows presented a lower loss of redness than meat from bulls. A low lipid oxidation was observed in VP samples, but an increase of lipid oxidation took place after MA repackaging. Meat from cows presented a higher -tocopherol content. A decrease of α-tocopherol content during storage was observed as well. The fat content was also higher in meat from cows than in meat from bulls. The duration and temperature of vacuum-packed storage influenced the sensitivity of Belgian Blue beef to pigment and lipid oxidation during subsequent high-oxygen storage. [less ▲]

Detailed reference viewed: 40 (15 ULg)