Enterobacteria Counts Research Articles

Effect of Different Immersion Tank Water Temperatures on the Microbiological Quality of Rabbit Carcasses

The pre-chilling of rabbit carcasses in an immersion tank directly interferes with microbial control. Therefore, this study was developed to examine the influence of different pre-chill tank water temperatures (4, 7, and 10 °C) on the microbiological quality of rabbit carcasses. Samples of rabbit carcasses and water and ice from the pre-chiller tank were collected; mesophilic aerobic heterotrophic microorganisms (MES), enterobacteria (EC), and coagulase-positive Staphylococcus (CPS) were counted; and the presence of Salmonella spp. was investigated. After the carcasses were immersed in the pre-chiller, there was a significant increase (p < 0.05) in MES (38.69 and 88.06 Log CFU·mL−1 at 4 and 10 °C, respectively) and EC (3.20, 4.15, and 4.84 Log CFU·mL−1 at 4, 7, and 10 °C, respectively). The average EC count tended to increase after the carcasses were immersed in the pre-chiller at different temperatures, but this increase was not significant. Water samples showed MES, EC, and CPS counts only after the immersion of the carcasses; however, the presence of these microorganisms was not detected in any of the ice samples. Salmonella spp. was not identified in the analyzed samples. The microorganisms analyzed at the three pre-chiller water temperatures evaluated did not multiply on the surface of the rabbit carcasses or in the pre-chiller water after carcass immersion. This study showed that none of the three pre-chilling temperatures were able to reduce the count of indicator microorganisms in the carcasses of rabbits. These data provide scientific support to discuss the need for specific norms and guidelines for rabbit meat production.

Diet supplementation with dalbergia palo-escrito hexane extract in fattening rabbits: its effect on productive performance, carcass traits, meat characteristics and meatballs Shelf-Life

This study was conducted to determine the influence of Dalbergia palo-escrito hexane extract supplemented to rabbits on productive performance, blood biochemistry, haematology, carcase traits, meat characteristics and meatballs shelf-life. A hexane extract of D. palo-escrito was obtained from leaves of the tree. Average feed consumption daily gain, average daily weight gain, total weight gain and feed conversion ratio, length body, lumbar circumference, carcase traits, texture profile analysis, meat colour, antioxidant properties, water activity as well as shelf life of meatballs (Total viable bacterial counts, staphylococcus counts, enterobacteria counts, antioxidant activity, pH and water activity) were determined. Feed conversion rate was lower (p < 0.05) in group feed with hexane extract (1.89 and 1.54, for control and hexane extract, respectively). Also, hexane extract decreases feed intake and weight gain. Hot dressing percentage was higher (p < 0.05) in the hexane extract group (48%) than the control group (47%), but the main carcase cuts were similar (p > 0.05) between groups. L* value was lower (p < 0.05) in the hexane extract group (51.2 vs 49.4, for control and hexane extract, respectively). The meatballs prepared with the meat obtained from the hexane extract group showed a lower (p < 0.05) total viable bacterial count after 14 d of storage in refrigeration conditions (8.45 and 4.75 CFU.g−1, for control and hexane extract group, respectively). D. palo-escrito hexane extract decreases productive performance, it is possible that albumin: globulin rate indicates a liver damage, but there no was effect on carcase and meat quality and it increased the shelf life of meatballs. Highlights Extracts of Dalbergia palo-escrito have bioactive compounds Dalbergia palo-escrito could be used to feed rabbits Meatballs increase shelf-life

Different periods of inclusion of acetic acid in broiler drinking water

The objective of this experiment was to evaluate the benefits of acetic acid in different periods of inclusion in broiler drinking water on broiler performance, pH, and microbiota, especially the morphometry of the jejunum of broiler chickens. For this, 240 chickens of the Cobb500® lineage of 21 days of age were used and distributed in boxes in an experimental broiler house, considering a completely randomized design, with four treatments and four replications of 15 birds each (experimental unit). The treatments were: T1 - Control (chlorinated water at 3 ppm); T2 - chlorinated and acidified water with acetic acid in the period from 21 to 42 days of age; T3- chlorinated and acidified water with acetic acid in the period from 28 to 42 days of age; T4 - chlorinated and acidified water with acetic acid in the period from 35 to 42 days of age. The results were analyzed using Analysis of Variance, followed by Tukey's post-test, considering a significance level of 5%. No differences in performance were observed in the period from 21 to 42 days of age, pH, and Lactobacillus spp. counts of the crop at 42 days of age and height of villi and jejunum crypt depth in the same age. However, there was a reduction (P&lt;0.05) in the enterobacteria count in the crop at 42 days of age, which could contribute to the reduction of intestinal enterobacteria counts and, in turn, reduce the contamination of the carcass of broiler chickens.

Characterization of Microbiological Quality of Whole and Gutted Baltic Herring.

There is growing interest in Baltic herring (Clupea harengus membras) and other undervalued, small-sized fish species for human consumption. Gutting or filleting of small-sized fish is impractical; hence, the aim of this study was to explore the suitability of the whole (ungutted) herring for food use. The microbiological quality of commercially fished whole and gutted herring was analysed with culture-dependent methods combined with identification of bacterial isolates with MALDI-TOF Mass Spectrometry and culture-independent 16S rRNA gene amplicon sequencing. Whole and gutted herring had between 2.8 and 5.3 log10 CFU g−1 aerobic mesophilic and psychrotrophic bacteria and between 2.2 and 5.6 log10 CFU g−1 H₂S-producing bacteria. Enterobacteria counts remained low in all the analysed herring batches. The herring microbiota largely comprised the phyla Proteobacteria, Firmicutes, and Actinobacteria (71.7% to 95.0%). Shewanella, Pseudomonas, and Aeromonas were the most frequently isolated genera among the viable population; however, with the culture-independent approach, Shewanella followed by Psychrobacter were the most abundant genera. In some samples, a high relative abundance of the phylum Epsilonbacteraeota, represented by the genus Arcobacter, was detected. This study reports the bacterial diversity present in Baltic herring and shows that the microbiological quality was acceptable in all the analysed fish batches.

Somatic Cell Number, Physicochemical, and Microbiological Parameters of Raw Milk of Goats During the End of Lactation as Compared by Breeds and Number of Lactations.

This study was aimed for the evaluation of somatic cell count (SCC), physicochemical, and microbiological parameters during the end of lactation in the raw milk of Alpine and native Red goat breed. In the experiment, 102 milk samples from Alpine and native Red goats were included. Two different groups within the same breed were analyzed: a group consisting of animals in their first lactation and the second group consisting of animals from the fifth lactation. The milk samples were individually and daily collected during late lactation for three consecutive weeks, and milk fat, protein, lactose, SCC, and total bacteria with enterobacteria were assessed. Fresh milk of goats from late lactation period had a number of somatic cells (SC) within the expected value with log10 of 5.8–6.18 cells/ml for the compared groups. In both breeds, the total mesophilic bacteria were fewer in numbers, however, in the native Red goat, a larger population of such bacteria was enumerated. The number of coliforms and enterobacteria was below 100 cfu/ml. In the current study, we were able to show a significant difference among the studied breeds depending on lactation and season for fat (p = 0.002), but not for lactose and protein content. A positive correlation for total protein (TP), lactose, and fat as well as for lactose and SCC was found in the native Red goat breed. In the Alpine goat breed, a strong positive correlation (0.821**) was found for lactose and enterobacteria count (EC). In conclusion, these findings evaluate different goat milk parameters during late lactation period and provide an indirect measure to monitor goat mammary gland health for both breeds.

Photohydroionisation for disinfection of poultry litter

ABSTRACT 1. This study evaluated photohydroionisation efficiency on the disinfection of new shavings used as substrate for litter in the poultry industry, pre-inoculated with bacterial, fungal and viral agents. 2. Each replicate consisted of 250 g of new shavings sterilised by autoclaving, challenged with bacterial (Escherichia coli, Staphylococcus aureus, and Salmonella enterica, serovar Abony), fungal (Saccharomyces cerevisiae) and viral inoculum (Gumboro disease virus). The experiment consisted of six replicates at four times (0, 1, 5 or 10 min exposure) of photohydroionisation. The disinfection process was performed in a bench photohydroionisation device with four ultraviolet lamps. The agents inoculated in the shavings were analysed after the disinfection process. 3. The counts of enterobacteria and total bacteria showed a quadratic effect. In contrast, the counts of fungi and viruses showed a negative linear effect with an increase in the time of photohydroionisation. The enterobacteria showed a linear response plateau effect (LRP), with a minimum time point of 5.498 minutes at a minimum contamination of 0.666 CFU/g and a reduction of 82.27% of the pre-established inoculum. Total bacteria had an LRP effect with a minimum time point of 1.902 minutes at minimum contamination of 1.739 CFU/g and a reduction of 50.0% of the pre-established inoculum. An LRP effect was found for fungi, with a minimum time point of 7.931 minutes in minimum contamination of 3.380 CFU/g, and with a reduction of 11.0% of the pre-established inoculum. For viruses, there was an LRP effect with a minimum time point of 5.012 minutes in minimum contamination of 0.000 viral titre per 100 g of shavings, which was reduced by 100% of the pre-established inoculum. 4. Photohydroionisation in the disinfection of new shavings used as poultry litter has partial potential as a microbiological control tool, as a complete reduction occurred only for the viruses, whereas for bacteria and fungi only partial reductions of these microorganisms were observed.

Quality Changes of Fresh-Cut Watermelon During Storage as Affected by Cut Intensity and UV-C Pre-treatment

The effect of a UV-C (0, 2.4, 4.8 and 7.2 kJ m−2) pre-treatment was studied during storage at 5 °C on quality changes of fresh-cut watermelon cylinders with different cut intensities (2.7 cm O; 1, 2, 4 or 8 cm length). The steady state of the modified atmosphere was reached on day 4 with 4.5–9.6 kPa CO2 + 14 kPa O2. UV-C treatments were more effective against enterobacteria since enterobacteria counts were better preserved during storage in 4 and 8 cm cylinders under 7.2 kJ m−2. The longest shelf life (7 days), based on sensory quality, was established for the biggest cylinders (8 cm) treated with 4.8 kJ m−2, while it was reduced to 5 days for the remaining UV-C doses, regardless of the cut intensity. Lycopene content (52.1–75.3 mg kg−1) was not affected by radiation treatments. After UV-C illumination, initial total phenolic contents (387–508 mg kg−1) were reduced, reporting less reductions for higher cut intensities. Initial total antioxidant capacity (1.32–2.44 mmol kg−1), mainly due to phenolic compounds and lycopene, was decreased after UV-C treatments. Total antioxidant capacity of UV-C samples was increased (2- to 14-fold) compared with untreated samples throughout storage as an antioxidant response of UV-stressed samples. Conclusively, fresh-cut watermelon cylinders of 8 cm length (2.7 cm O) better preserved their quality during storage compared with smaller cylinders, with a shelf life of 7 days when a 4.8-kJ m−2 UV-C dose was applied.

Evaluation of the combined effects of different dose levels of Zinc oxide with probiotics complex supplementation on the growth performance, nutrient digestibility, faecal microbiota, noxious gas emissions and faecal score of weaning pigs.

This study was conducted to assess the effects of different dose levels of zinc oxide (ZnO) combined with probiotics complex supplementation on the growth, performance, nutrient digestibility, faecal lactobacillusandEnterobacteriacounts, noxious gas emissions and faecal score of weaned piglets. A total of 180 crossbred weaning pigs ([Yorkshire×Landrace]×Duroc; 6.61±1.29kg [mean±SE]; 28days old) were used in a 42-day trial. All pigs were randomly allotted to 1 of 4 treatment diets based on initial BW and sex (9 replicate pens/treatment; 2 gilts and 3 barrows/pen). Dietary treatment groups were as follows: CON, basal diet +ZnO 3,000ppm; BZS, basal diet +ZnO 2,100ppm +0.1% SynerZymeF10; BZS1, basal diet +ZnO 1,200ppm +0.1% SynerZymeF10; BZS2, basal diet +ZnO 300ppm +0.1% SynerZymeF10. During the phase 3, decreasing the ZnO concentration led to a linear reduction in ADG (p=0.044), and the ADG was lower (p<0.05) in BZS2 compared with CON treatment during the whole experimental period. The effects of dietary ZnO with probiotics complex were not detected (p>0.05) on nutrient digestibility, Lactobacillus and E.coli counts, faecal gas emissions and faecal scores. In conclusion, the diet supplementation of ZnO (1,200ppm) with probiotics complex has been shown to have comparable efficacy to ZnO (3,000ppm) diet on growth performance, nutrient digestibility, faecal microbiota, noxious gas emissions and faecal score of weaning pigs.

Influence of the Fermented Feed and Vaccination and Their Interaction on Parameters of Large White/Norwegian Landrace Piglets.

Simple SummaryFarm animals are constantly exposed to pathogenic microorganisms, which can lead to bacterial, as well as secondary infections caused by viruses. For this reason, vaccination is used. However, many discussions have been published about the effectiveness of this prophylactic measure. The aim of this study was to evaluate the influence of fermented feed on non-vaccinated (NV) and vaccinated with Circovac porcine circovirus type 2 vaccine piglets’ blood parameters, gut microbial composition, growth performance and ammonia emission. The 36-day experiment was conducted using 25-day-old Large White/Norwegian Landrace piglets, which were randomly divided into four groups each comprising 100 piglets (NV piglets fed with soya meal, vaccinated piglets fed with soya meal, NV piglets fed with fermented rapeseed meal and vaccinated piglets fed with fermented rapeseed meal). The results revealed that vaccination, as a separate factor, did not significantly influence piglets’ blood parameters. Finally, rapeseed meal fermented with the selected lactic acid bacteria strains can be used instead of expensive imported soya, because the fermented feed did not cause undesirable changes in piglets’ health and growth performance. Furthermore, the process is more sustainable.The aim of this study was to evaluate the influence of fermented with a newly isolated lactic acid bacteria (LAB) strains combination (Lactobacillus plantarum LUHS122, Lactobacillus casei LUHS210, Lactobacillus farraginis LUHS206, Pediococcus acidilactici LUHS29, Lactobacillus plantarum LUHS135 and Lactobacillus uvarum LUHS245) feed on non-vaccinated (NV) and vaccinated with Circovac porcine circovirus type 2 vaccine (QI09AA07, CEVA-PHYLAXIA Co. Ltd. Szállás u. 5. 1107 Budapest, Hungary) piglets’ blood parameters, gut microbial composition, growth performance and ammonia emission. The 36-day experiment was conducted using 25-day-old Large White/Norwegian Landrace (LW/NL) piglets, which were randomly divided into four groups with 100 piglets each: SnonV—non-vaccinated piglets fed with control group compound feed; SV—vaccinated piglets fed with control group compound feed; RFnonV—non-vaccinated piglets fed with fermented compound feed; RFV—vaccinated piglets fed with fermented compound feed. Samples from 10 animals per group were collected at the beginning and end of the experiment. Metagenomic analysis showed that fermentation had a positive impact on the Lactobacillus prevalence during the post-weaning period of pigs, and vaccination had no negative impact on microbial communities. Although a higher amount of Lactobacillus was detected in vaccinated, compared with non-vaccinated groups. At the end of experiment, there was a significantly higher LAB count in the faeces of both vaccinated compared to non-vaccinated groups (26.6% for SV and 17.2% for RFV), with the highest LAB count in the SV group. At the end of experiment, the SV faeces also had the highest total bacteria count (TBC). The RFV group had a 13.2% increase in total enterobacteria count (TEC) at the end of experiment, and the SV group showed a 31.2% higher yeast/mould (Y/M) count. There were no significant differences in the average daily gain (ADG) among the groups; however, there were significant differences in the feed conversion ratios (FCR) between several groups: SV vs. SnonV (11.5% lower in the SV group), RFV vs. RFnonV (10.2% lower in the RFnonV group) and SV vs. RFV (21.6% lower in the SV group). Furthermore, there was a significant, very strong positive correlation between FCR and TEC in piglets’ faeces (R = 0.919, p = 0.041). The lowest ammonia emission was in RFV group section (58.2, 23.8, and 47.33% lower compared with the SnonV, SV and RFnonV groups, respectively). Notably, there was lower ammonia emission in vaccinated groups (45.2% lower in SV vs. SnonV and 47.33% lower in RFV vs. RFnonV). There was also a significant, very strong positive correlation between ammonia emission and Y/M count in piglets’ faeces at the end of the experiment (R = 0.974; p = 0.013). Vaccination as a separate factor did not significantly influence piglets’ blood parameters. Overall, by changing from an extruded soya to cheaper rapeseed meal and applying the fermentation model with the selected LAB combination, it is possible to feed piglets without any undesirable changes in health and growth performance in a more sustainable manner. However, to evaluate the influence of vaccination and its interaction with other parameters (feed, piglets’ age, breed, etc.) on piglets’ parameters, additional studies should be performed and methods should be standardised to ensure the results may be compared.

Intestinal microbiota modulation in juvenile Pacú (Piaractus mesopotamicus) by supplementation with Pyropia columbina and β-carotene

The aim was to evaluate the effects of diet supplementation with red seaweed Pyropia columbina or β-carotene on the intestinal microbiota of juvenile Pacu (Piaractus mesopotamicus). Three hundred and fifteen fish (body weight 12.4 ± 2.8 g) were stocked in nine 300-L tanks with 35 fishes per tank and fed for 62 days with a basal feed (BG) or the same feed added with P. columbina (35 g kg−1) (AG) or supplemented with β-carotene (225 g kg−1) (β-CG). From fecal samples of three fishes slaughtered per group at 20th, 41th, and 62th days, plate counts of bacterial populations (enterobacteria, lactic acid bacteria—LAB, total aerobes, and psychrotrophs) and DGGE were made. Enterobacteria counts were lower in AG-group than the other groups throughout the experience (p = 0.016). LAB/enterobacteria ratio was greater in fishes supplemented with AG on 20th day, showing a greater amount of beneficial bacteria than non-beneficial ones. DGGE profiles resulting from the microbiota of β-CG at 62th day were clustered and separated from the rest of the profiles with a difference of 91%. Margalef richness (p = 0.049) and Shannon diversity index (p = 0.044) were lower in β-CG than in AG at 62th day. Taxonomic characterization showed the presence of three phylum: Bacteroidetes, Firmicutes, and Fusobacteria. This is the first study in which the microbiota of juvenile Pacu fed with biofunctional diets was evaluated. Future interventions that modify the bacterial ecosystem could improve the productive performance and ensure the safety of the pacu meat intended for consumption.

Agar-immobilized basil–lactic acid bacteria bioproducts as goat milk taste-masking agents and natural preservatives for the production of unripened goat cheese

Goat milk cheeses have become popular recently; however, many consumers do not choose these products because they have specific sensory properties that are not acceptable to all consumers and the shelf life of the cheese is short. The concept of this work was to increase overall acceptability and shelf life of unripened goat milk cheese by using Ocimum basilicum and lactic acid bacteria (Lactobacillus plantarum LUHS135, Lactobacillus paracasei LUHS244, Pediococcus pentosaceus LUHS100, Pediococcus acidilactici LUHS29, and Lactobacillus brevis LUHS140) bioproducts (basil-LAB) immobilized in agar. A basil-LAB bioproduct could be a promising multifunctional ingredient for cheese manufacturing because it has a low pH, high LAB count, and high total phenolic compound content (after fermentation pH decreased by 25.4%, LAB count averaged 7.2 log10 cfu/g, and total phenolic compound content increased by 30.9%). Use of different LAB in the preparation of basil-LAB bioproducts had a significant influence on cheese pH and hardness, and compared with cheese samples prepared with nonfermented basil, cheese samples prepared with basil-LAB bioproducts had, on average, higher pH (by 2.6%) and lower hardness (by 36.0%), similar to the control cheese (without basil). Overall acceptability of cheese was significantly influenced by the basil-LAB bioproduct immobilization process; in all cases, cheese samples prepared with fermented and immobilized basil-LAB bioproduct had better acceptability (5 points). After 120 h of storage, cheese samples prepared with basil-LAB bioproducts fermented with LUHS135, LUHS244 and LUHS140, no enterobacteria were found, and we detected strong negative and moderate negative correlations, respectively, of LAB count with enterobacteria count and yeast/mold count (r = -0.7939 and r = -0.4495, respectively). Finally, immobilization increased LAB viability in fresh goat milk cheese, which led to a reduction in enterobacteria and mold/yeast contamination during storage and an increase in overall acceptability compared with nonimmobilized basil-LAB. Therefore, basil-LAB bioproducts fermented with LUHS135, LUHS244, and LUHS140 strains can be recommended for preparing fresh goat milk cheese with extended shelf life and high acceptability.

Chemical, physical and biological changes of white oat ensiled with different additives

SUMMARY This study evaluated the addition of inoculants on the aerobic stability, nutritional value, and fermentation and microbiological profiles of white oat silages (Avena sativa L.). The trial was carried out in a completely randomized design with three treatments and six replicates. The treatments consisted of three ensiling approaches: oat (O); oat with homofermentative bacterial inoculant (OB); and oat with bacterial-enzymatic inoculant (OBE). The aerobic stability was 9 days for silage O and 14 days for silages OB and OBE. The non-fiber carbohydrates (NFC) decreased (16.67 to 14.05% DM) and the crude protein (CP) did not change (mean of 8.98% DM) during the aerobic exposure in all silages. The buffering capacity (BC) decreased, while pH and the ammonia nitrogen (NH3-N) increased during the aerobic exposure in all silages. Independent from the aerobic exposure period, BC of OBE silage was higher than O silage (29.67 vs. 24.80 meq/100 g DM). Lactic acid bacteria count in OB silage (7.83 log CFU/g) was higher than in O and OBE silages (5.24 log CFU/g, on average). Also, the OB silage showed high enterobacteria count compared to OBE silage (2.49 vs. 0.76 log CFU/g). The inoculation with Lactobacillus plantarum, Pediococcus acidilactici and amylase enzyme at the dose of 1×105 CFU/g does not improve the aerobic stability, nutritional value and the fermentation and microbiological profiles of oat silages.

Bacterial communities of fresh goat meat packaged in modified atmosphere

The objective of this work was to study the growth and development of fortuitous flora and food pathogens in fresh goat meat packaged under modified atmospheres containing two different concentrations of CO2. Meat samples were stored at 10 °C under two different modified-atmosphere packing (MAP) conditions: treatment A had 45% CO2 + 20% O2 + 35% N2 and treatment B had 20% CO2 + 55% O2 + 25% N2. During 14 days of storage, counts of each bacterial group and dominant species identification by 16S rRNA gene sequencing were performed to determine the microbial diversity present. The MAP condition used for treatment A was a more effective gas mixture for increasing the shelf life of fresh goat meat, significantly reducing the total number of viable bacteria and enterobacteria counts. Members of the Enterobacteriaceae family were the most common contaminants, although Hafnia alvei was dominant in treatment A and Serratia proteamaculans in treatment B. Identification studies at the species level showed that different microorganisms develop under different storage conditions, reflecting the importance of gas composition in the modified atmosphere on the bacterial community. This work provides new insights into the microbial changes of goat meat storage under different MAP conditions, which will be beneficial for the meat industry.

Desempenho de bezerros leiteiros recebendo probiótico contendo Bacillus subtilis e Bacillus licheniformis

RESUMO Foram utilizados 24 bezerros que receberam 4L/dia de sucedâneo, além de livre acesso a água e concentrado até a 8a semana. Os animais foram distribuídos em delineamento de blocos casualizados, em dois tratamentos: 1) Controle: sem a suplementação de probiótico; 2) Suplementação de 2g/d de Bacillus subtilis e Bacillus licheniformis via sucedâneo lácteo. Semanalmente os animais foram pesados e foram aferidas as medidas corporais; também foram realizadas colheitas de sangue para determinação de glicose, proteína total, ureia e albumina, além de hematócrito. Foram colhidas amostras de fezes semanalmente para contagem de bactérias ácido láticas e enterobactérias e determinação de pH fecal. O peso corporal, o ganho de peso médio diário e as medidas corporais não foram alteradas pela suplementação; muito embora tenham apresentado efeito significativo de idade dos animais. O escore fecal, pH fecal e consumo de concentrado diário também não foram afetados pela suplementação. No entanto, o consumo de concentrado e o pH fecal sofreram influência da idade em resposta ao crescimento natural dos bezerros. A contagem de bactérias ácido láticas foi maior em número do que a contagem de enterobactérias durante todo o período. Apenas as enterobactérias sofreram efeito da idade, enquanto as bactérias ácido láticas permaneceram variando, porém dentro de um padrão constante. Os parâmetros sanguíneos também não foram afetados pela suplementação com probiótico mas todos, com a exceção da albumina, tiveram influência da idade. A suplementação com o probiótico não apresentou benefícios no desempenho ou no metabolismo de bezerros leiteiros, também não reduziu a ocorrência de casos de diarreia.

DIAGNOSIS OF EGG MARKETING CONDITION IN SINOP - MT

The eggs, when manipulated in inadequate sanitary conditions, are considered as ways for development and multiplication of spoilage and pathogenic microorganisms. Thus, the objective was to evaluate the microbiological quality of eggs marketed out at Sinop – MT, through the identification of Salmonella spp., count of aerobic mesophile bacteria and enterobacteria. We collected 12 eggs from each establishment, three supermarkets and three fairs. Were not identified Salmonella spp. in egg shells and internal content. Escherichia coli was isolated from the internal contents of eggs come from an street fair. In aerobic mesophilic counts were obtained from eggs supermarkets counts CFU/g/egg shell of 5,8 x 10 5 , 1,21 x 10 5 e 4,7 x 10 3 . In relation to the fairs, the counts were 7,2 x 10 4 , 5,66 x 10 4 e 8,7 x 10 3 . The absence of Salmonella spp. the evaluated eggs classifies them as fit for consumption for compliance with current legislation. However, the presence of E. coli and the values of aerobic mesophilic counts and Enterobacteriaceae highlight the need to establish measures to reduce bacterial contamination of shell eggs sold out at Sinop, MT.

Cheese production using kefir culture entrapped in milk proteins.

The aim of the present study was to evaluate the use of kefir culture entrapped in casein and in whey protein as starter cultures for the production of Feta-type cheese. Microbiological analysis showed that counts of enterobacteria, coliforms, and staphylococci were significantly reduced due to kefir culture. In addition, the effect of kefir culture on the formation of volatile compounds, such as esters, organic acids, alcohols, carbonyl compounds, and lactones, was also investigated using the SPME GC/MS technique. Cheese samples produced with kefir culture entrapped in milk proteins presented improved profile of aroma-related compounds. Principal component analysis of the results indicated that the volatile composition of the different cheese types was dependent on the nature of the starter culture. Finally, the sensory evaluation showed that the products produced with kefir culture had a soft, fine taste, and were of improved quality.

Sterilization and aseptic packaging of soymilk treated by ultra high pressure homogenization

Ultra high pressure homogenization (UHPH) was applied on soymilk to produce an aseptically packaged beverage. UHPH-treated soymilk (300 MPa, 80 °C inlet temperature and 144 °C/0.7 s at the homogenization valve) was compared with samples treated by ultra high temperature (UHT) at 142 °C for 6 s. After treatment, soymilk samples were aseptically packaged in coated paperboard cartons of 200 mL Tetra Brik containers. Tetra Brik containers were stored for 6 months at room temperature and analyzed at different days. Microbiological (total mesophilic aerobic bacteria, aerobic spores, Bacillus cereus , and enterobacteria counts), physical (dispersion stability and particle size distribution), chemical (hydroperoxide index and volatile profile evolution) and sensory analyses were performed on soymilks. Both UHPH and UHT soymilks did not present microbiological growth during storage. UHPH soymilk presented high colloidal stability and relevant decrease in hydroperoxide index during storage. On the other hand, almost all of the compounds associated to off-flavors were detected in the volatile profile of soymilk. Sensory results indicated that UHPH treatment did not produce changes in soymilk which could affect the panel perception for different UHT and UHPH soymilks and for selecting their preference. Soymilk constitutes one of the food industry sectors with the highest worldwide growth and its consumption has experienced a noticeable increase in the last years. The growing consumer demand for safe products, environmentally friendly processes and high quality nutritional foods has challenged the food industry to adapt the technological processes. This tendency impacts directly on traditional technologies, like heat treatments. In this sense, UHPH technology has been applied as an alternative to those thermal treatments. This research paper presents a comparative study between soymilk treated by UHPH and by UHT to produce a product stored at room temperature for 6 months. Results showed stable levels of oxidation, high physical stability, no microbial growth and a positive trend of sensory response during the period analyzed for UHPH soymilk. Moreover, the UHPH system was designed to work at continuous flow, allowing its application in several industrial food processes. • UHPH and UHT soymilks did not present microbial growth over 180 days of storage. • UHPH soymilks showed high physical stability during storage at room temperature. • UHPH soymilks presented relevant decrease in hydroperoxide index during storage. • Hexanal values showed important decrease during storage of UHPH soymilks. • Panelist was not able to identify the differences between UHT and UHPH treatments.

Predominant enterobacteria on modified-atmosphere packaged meat and poultry

Enterobacteria on modified-atmosphere (MA) packaged meat (n = 54) and poultry (n = 32) products were enumerated, and 899 isolates were picked and ribotyped. For identification, 16S rRNA genes of representative strains were sequenced and analyzed. Altogether 54 (60%) of the samples contained enterobacteria >104 CFU/g. In 34% of the poultry samples, enterobacteria counts were >106 CFU/g suggesting that enterobacteria may contribute to spoilage of MA packaged poultry. The enterobacteria identified were predominantly Hafnia spp. (40%) and Serratia spp. (42%) with Hafnia alvei, Hafnia paralvei, Serratia fonticola, Serratia grimesii, Serratia liquefaciens, Serratia proteamaculans, and Serratia quinivorans being the species identified. In addition, 6% of the isolates were identified as Rahnella spp., 3% as Yersinia spp., and 1% as Buttiauxella spp. Percentage distributions of the predominant genera in different products showed that 89% of the Serratia spp. were from products packaged under a high-O2 MA containing CO2 (25–35%), whereas most (76%) isolates of Hafnia originated from anaerobically packaged red meat and poultry. These findings suggest that the gas mixture used for MA packaging influence the selection of enterobacteria growing on meat and poultry.

Effects of Ginger (Zingiber officinale) Oil on Growth Performance and Microbial Population of Broiler Ross 308

2 Abstract: An experiment was conducted at the University of Kirkuk, poultry farm of college of agriculture department of animal science to evaluate the effect of ginger oil on growth performance and microbial population of broiler chickens. Two hundred male and female day old chicks of Ross308 were arranged in a complete random design experiment and allotted to one of four treatments doses 0 (Control),10mg/kg/day (T1), 20mg/kg/day (T2) and 40mg/kg/day (T3). The trial lasted for seven weeks and there were no differences in feed intake, body weight gain and the feed conversion ratio among the birds, All organs weight and carcass characteristics were not affected by the treatments, except for a decrease (P<0.05) in relative liver weight of birds those given ginger oil treatment compared with control. Similarly, a lower (P<0.001) proportion of the head weight of birds given ginger oil was observed compared to the control. Dosages effects showed a decrease in relative weight of organs only for the head (P<0.001) and the gizzard (P<0.05) compared to the control. Male broilers deposited less (P<0.001) than the females. There were no significant differences observed in the activities of the serum transaminases (AST and ALT) and blood creatinine level, indicating that none of the three dosages of oil given to birds was toxic. However, Escherichia coli and other Enterobacteria counts in the ileo-caecal digesta numerically decreased (P<0.05) compared to the control as the doses of oil given increased. The same observation was made for the Salmonella and Shigella species (P<0.001).The Colony Forming Units (CFU) of Staphylococci spp were statistically significantly (P<0.01) reduced compared with the control group. Yeast and mold fungi were found in the ileo-caecal digests of all the groups.

Innovative Cooking Techniques for Improving the Overall Quality of a Kailan-Hybrid Broccoli

The microbial, physical, sensory and nutritional quality of boiled (vacuum and conventional), steamed, pressure cooked, sous vide, microwaved (sous vide and conventional), deep-fried (vacuum and conventional) and grilled kailan-hybrid broccoli (Bimi®) after cooking was studied. Sous vide microwaving greatly decreased microbial counts, achieving very low psychrophilic and enterobacteria counts (1.1 and 0.2 log CFU g−1, respectively). Vacuum boiling and sous vide reduced the stem broccoli firmness by approximately 54–58 %, reaching a pleasant and moderate softening. Sous vide, grilling and steaming induced the lowest stem colour changes. Generally, all cooking treatments showed a good overall sensory quality. The total phenolic content (1,148 mg CAE kg−1 fw) usually increased after cooking, with microwave and grilled treatments registering the highest increases up to 2-fold. Commonly, the total antioxidant capacity (296.6 mg AAE kg−1 fw) increased after cooking by sous vide, microwaving and frying treatments registering the highest increments, by approximately 3.6-fold. Generally, the cooking process reduced the initial vitamin C content, with vacuum and conventional boiling showing the lowest and highest losses with 27 and 62 %, respectively, while vacuum deep frying preserved the initial value (1,737 mg kg−1 fw). As a main conclusion, the studied grilling and vacuum-based cooking treatments resulted in better microbial quality, colour, stem firmness and sensory quality than the remaining ones. This maintained or even improved the total antioxidant content of the new kailan-hybrid broccoli studied.