Meat Broth Research Articles

Combination of Origanum vulgare L. essential oil and lactic acid to inhibit Staphylococcus aureus in meat broth and meat model.

This study assessed the occurrence of an enhancing inhibitory effect of the combined application of Origanum vulgare L. essential oil and lactic acid against Staphylococcus aureus by the determination of Fractional Inhibitory Concentration (FIC) index and cell viability in meat broth and meat model. Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the oil was 0.6 and 1.25 µL.mL-1, respectively. Lactic acid showed MIC and MBC of 2.5 and 5µL.mL-1, respectively. FIC indices of the combined application of the oil and lactic acid were 0.5 showing a synergic interaction. The essential oil and lactic acid showed similar (p>0.05) anti-S. aureus effect in meat broth over 96 h of exposure. Treatment with essential oil or lactic acid presented a smaller anti-staphylococcal effect in meat in comparison to meat broth. No significant difference (p>0.05) was found for the microbial counts in meat treated with each antimicrobial alone or in mixture. These results could arise as an interesting approach for the improvement of food preservation using more natural procedures, considering the current demand of consumer and sensory quality of foods.

Promoting Bacillus cereus spore germination for subsequent inactivation by mild heat treatment.

Sublethal heat treatment may activate dormant spores and thereby potentiate the conversion of spores to vegetative cells. As the germinated spore is known to possess lower heat resistance than its dormant counterpart, it has been postulated that double heat treatment, i.e., spore heat activation followed by germination and then by heat inactivation, can be used to control spores in foods. Production of refrigerated processed foods of extended durability often includes more than one heat treatment of the food components. This work simulates conventional heat treatment procedures and evaluates double heat treatment as a method to improve spore control in model food matrixes of meat broth and cream sauce. Bacillus cereus NVH 1230-88 spores were supplemented in food model matrixes and heat activated at 70°C and then heat inactivated at 80 or 90°C. The samples were held at 29 to 30°C for 1 h between primary and secondary heat treatments, to allow spore germination. Nutrients naturally present in the food matrixes, e.g., amino acids and inosine, could act as germinants that induce germination. The levels of germinants could be too low to produce effective germination within 1 h. Following primary heat treatment, some samples were therefore supplemented with a combination of L-alanine and inosine, a germinant mixture known to be effective for B. cereus spores. In both matrixes, a combination of double heat treatment (heat activation, germination, and inactivation) and addition of germinants gave a reduction in spore counts equivalent to or greater than that obtained with a single heat treatment for 12 min at 90°C. Addition of germinants was essential to induce effective germination in cream sauce during 1 h at 29 to 30°C, and germinants were therefore a crucial supplement to obtain an effect of double heat treatment in this matrix. These data will be valuable when setting up temperature-time-germinant combinations for an optimized spore reduction in mild-heat-treated foods.

Characterisation and Carriage Ratio of Clostridium difficile Strains Isolated from a Community-Dwelling Elderly Population in the United Kingdom

BackgroundCommunity-associated Clostridium difficile infection (CDI) appears to be an increasing problem. Reported carriage rates by C.difficile are debatable with suggestions that primary asymptomatic carriage is associated with decreased risk of subsequent diarrhoea. However, knowledge of potential reservoirs and intestinal carriage rates in the community, particularly in the elderly, the most susceptible group, is limited. We have determined the presence of C.difficile in the faeces of a healthy elderly cohort living outside of long-term care facilities (LCFs) in the United Kingdom.MethodsFaecal samples from 149 community-based healthy elderly volunteers (median age 81 years) were screened for C.difficile using direct (Brazier's CCEY) and enrichment (Cooked Meat broth) culture methods and a glutamate dehydrogenase (GDH) immunoassay. Isolates were PCR-ribotyped and analysed for toxin production and the presence of toxin genes.ResultsOf 149 faecal samples submitted, six (4%) were found to contain C.difficile. One particular sample was positive by both the GDH immunoassay and direct culture, and concurrently produced two distinct strain types: one toxigenic and the other non-toxigenic. The other five samples were only positive by enrichment culture method. Overall, four C.difficile isolates were non-toxigenic (PCR-ribotypes 009, 026 (n = 2) and 039), while three were toxigenic (PCR-ribotypes 003, 005 and 106). All individuals who had a positive culture were symptom-free and none of them had a history of CDI and/or antibiotics use in the 3 month period preceding recruitment.ConclusionsTo our knowledge, this is the first study of the presence of C.difficile in healthy elderly community-dwelling individuals residing outside of LCFs. The observed carriage rate is lower than that reported for individuals in LCFs and interestingly no individual carried the common epidemic strain PCR-ribotype 027 (NAP1/BI). Further follow-up of asymptomatic carriers in the community, is required to evaluate host susceptibility to CDI and identify dynamic changes in the host and microbial environment that are associated with pathogenicity.

Sterile Surgical Helmet System in Elective Total Hip and Knee Arthroplasty

To evaluate the sterility of the sterile surgical helmet system (SSHS) during elective total hip and knee arthroplasty in theatres with (n=20) and without (n=20) laminar flow. Three surgeons performed 14 total knee arthroplasties (TKAs) and 6 total hip arthroplasties (THAs) in a laminar flow theatre and 15 TKAs and 5 THAs in a non-laminar flow theatre. An SSHS was used in all the procedures. Samples were taken from the hood at 30-minute intervals during surgery. Swabs were then broken into cooked meat broths for cultivation of organisms. The broths were then directly inoculated onto blood agar and fastidious anaerobic agar for culture of aerobic and anaerobic bacteria, respectively. After 24 hours, these plates were reinoculated with broths that had been incubated for 24 hours. Microbial growth was quantified as 0 (none), 1 (mild), 2 (moderate) and 3 (heavy). Bacterial contamination in the 2 groups at 30, 60 and 90 minutes was compared. Respectively in the laminar and non-laminar flow theatres, 0 and 9 of the SSHSs showed bacterial growth after direct inoculation, and 14 and 18 of the SSHSs grew 18 and 24 types of organisms in the swab cultures after 24 hours of incubation. Respectively at 30, 60, and 90 minutes, the degree of contamination from direct incubation was significant, but the degree of contamination on swabs after 24 hours of inoculation was not significant. The mean time-dependent contamination after direct inoculation was 0 for the laminar flow group and 0.5, 0.75, and 1.0 for the non-laminar flow group, whereas the corresponding values after 24 hours of incubation were 1.8, 1.8, and 2.6, and 2, 2.75, and 2.95. Coagulase negative Staphylococcus aureus was the most common organism in both groups. 80% of SSHSs used were contaminated intra-operatively. Direct contact with the SSHS should be avoided by the operating team during surgery. Routine changing of gloves in case of contact with the SSHS should be practised.

A Historical Study on the Changes in the Recipe of Naengmyeon (Korean Cold Noodles) Base on Water - Focus on the Recipe Data Published in Korea from 1800’s to 1980’s -

The mainly purpose of this research was to investigate tendency of changes regarding the recipe of Naengmyeon (Korean cold noodles) based on water. In order to conduct of this research, we analyze the recipe data published in Korea from 1800's to 1980's. A method of mainly study was conducted by content analysis and literature review. The documents of recipe used research were 42 literatures (euigwae, recipe book, magazines, and dictionaries). In addition, the recipes of Naengmyeon based on water were total method of 84. The results of an analysis of recipe data published in the last 200 years showed 3 different types of the recipe of Naengmyeon based on water; 1) Naengmyeon based on water of Kimchi juice type 2) Naengmyeon based on water of (meat) broth type 3) Naengmyeon based on water of mixed (Kimchi juice+broth) type.

Koji fermentation based on extracellular peptidases of Flammulina velutipes

A total of 28 basidiomycetes and 16 substrates were investigated to detect extracellular peptidases for the hydrolysis of wheat gluten as a complex Koji substrate. In a first screening, basidiomycetes were grown in submerged cultures containing gluten as only carbon and nitrogen source. Growth rate, protein concentration and peptidase activity were monitored. Flammulina velutipes, Armillaria mellea, Trametes versicolor, Meripilus giganteus, Fomitopsis pinicola, Phanerochaete chrysosporium and Hericium erinaceus showed high peptidase activity. To evaluate the effects of complex substrates on peptidase generation, a set of experiments was performed using surface cultures of Flammulina velutipes. This fungus grew well on many of the substrates and yielded a maximum of over 160.000 arbitrary U mL−1 on the surface liquid released from gluten pellets. Gelatin zymography visualized a complex mixture of secreted peptidases. Highest peptidase yield was obtained from a koji-type culture: A maximum of 63% of the gluten was converted to free amino acids in 14 days by peptidase activities in the range of 80,000–90,000 aU mL−1. The dark brown hydrolysate smelled and tasted like meat broth with no detectable bitterness.

Schematic Method for Effective Identification of Anaerobes from Infected Surgical Wounds

Objective: To investigate post surgical wound infections for anaerobes and to develop effective method for their rapid identification. Method: Fifty seven (57) samples were collected in cooked meat broth, they consisted of 40 wound swabs, 7 pus, 6 vaginal and 4 rectal swabs. They were inoculated into two compounded media; Neomycin Blood Agar (NBA) and Neomycin Plasma Agar (NPA) incubated anaerobically at 37oC for (24-48) hours. Isolated anaerobes were gram-stained and tested using discs impregnated with antibiotics, bile salts and dyes, carbohydrate fermentation and other standard tests were carried out. Results: Abdominal surgery had the highest anaerobes (44%), Musculoskeletal (25%), Splenectomy and related procedures (5%). Severe outcomes associated with anaerobes were amputation of limbs and death. Anaerobes were classified into fragilis group, bile resistant, bile sensitive and Fusobacterium group. Further tests revealed Bacteroides fragilis, Fusobacterium nucleatium, Porphyromonas assacharolytica, Prevotella intermedia, and Peptosterptococcus magnus as most frequently isolated. The developed scheme interlinked the various identification steps: 1st level; inoculation and growth, 2nd level; Gram differentiation and 3rd level; Biochemical characterization. Conclusion: The study has shown anaerobic cultures as essential in the management of patients with post surgical would infections. The scheme serves as a guide of idealized representation to identification of anaerobes. KEY WORDS: Anaerobes, Culture, Compounded media, Schematic, Surgical wounds

Listeria monocytogenesEfficiently Invades Caco-2 Cells After Low-Temperature Storage in Broth and on Deli Meat

The objective of this study was to investigate how various growth conditions influence the virulence of Listeria monocytogenes monitored by its ability to invade the epithelial cell lines Caco-2 and INT-407. The growth conditions examined were modified atmosphere-packaged deli meat and brain heart infusion broth (BHI) with and without salt. Five strains of L. monocytogenes were selected to investigate their invasiveness and all strains invaded Caco-2 cells at higher levels than INT-407 cells. Further, the clinical strains (3443 and 3734) were more invasive (p < 0.05) than the strains isolated from meat and food-processing environments (3008, 3126, and 4140) after grown in BHI at 30 degrees C. This attenuation could not be ascribed to a defective Internalin A as all strains encoded an intact inlA gene. To determine the influence of food products on virulence, the ability of L. monocytogenes to invade Caco-2 cells was compared after growth on a fermented sausage and on cured cooked ham to that of bacteria grown in BHI broth supplemented with salt. Samples were stored under chilling conditions for up to 4 weeks. The results showed no difference (p > 0.05) in invasiveness after 7 days at 10 degrees C in BHI broth or on sausage, whereas a slight increase (p < 0.05) was observed after incubation on ham for 2 and 4 weeks compared to that in BHI broth. Most importantly, our results show that L. monocytogenes efficiently invade Caco-2 cells even after 4 weeks of storage at chilled temperature. This is highly relevant for safety assessment of this organism in food as these conditions reflect storage of ready-to-eat food products in domestic refrigerators.

Epidemiological study on hyperuricemia and gout in Foshan areas, Guangdong province

To determine the prevalence rates and risk factors of hyperuricemia (HUA) and gout among residents aged over 20 years in Foshan areas. A randomly stratified cluster sampling was conducted, and 7403 inhabitants were investigated on their prevalence rates of HUA and gout. (1) The prevalence of HUA was 15.09%, and the standardized rate was 15.27%, in which the prevalence in males was 19.90% and females was 10.54%. The prevalence of gout was 1.04% and the standardized rate was 1.08%, in which the prevalence in males was 1.73% and females was 0.39%. The prevalence of gout in patients with HUA was 6.89%. (2) Average serum uric acid was (336.4 ± 81.5) µmol/L, with (347.1 ± 88.6) µmol/L in males and (289.7 ± 78.6) µmol/L in females. The serum uric acid levels in male patients with HUA was higher than those in women. (3) Age, body mass index, systolic blood pressure, diastolic blood pressure, serum uric acid, blood sugar, triglyceride (TG), total cholesterol were significantly higher in patients with HUA and gout than in the normal group (P < 0.05 - 0.01). The incidence rates of patients with hyperuricemia and gout in the following indices as:overweight and obesity, high blood pressure, high blood sugar were significantly higher than those in the normal group (P < 0.05). Patients having gout in the following indices as age, TG, serum uric acid levels were significantly higher than the HUA group (P < 0.05). (4) Data from non-conditional logistic regression analysis showed that age, overweight, hypertension, diabetes, hyperlipidemia, use of diuretics, family history, alcohol uptake, eating seafood and drinking meat broth, post-menopausal women, and other factors were similar to those factors as patients with hyperuricemia. Tea, fresh vegetables, fruits seemed to be the protective factors. Both the prevalence rates of HUA and gout had significantly increased in Foshan areas in recent years. Restricting the intake of food with rich purine, alcohol intake as well as controlling obesity and blood pressure, improving the status of lipid metabolic disorder together with programs as hypertension control etc. were important measures in the strategies on prevention and treatment on hyperuricemia and gout.

Perceptive maps of dishes varying in glutamate content with professional and naive subjects

The present study was undertaken to examine how western subjects perceive umami taste and how they can sensory discriminate among dish variants having different natural umami taste (glutamate) levels. The food matrix used in this study was prepared following a traditional Italian recipe of asparagus soup with ingredients having natural high endogenous content of umami compounds (i.e. Parmigiano, commercial meat broth, and fresh asparagus). The ingredients ratio was modified in order to modulate the flavour and, in particular, the umami taste. The study enrolled two groups of subjects: one group of panellists tested for normal taste perception but with no sensory training, and a second group of professional panellists trained in the recognition and quantification of umami taste. Panellists in both groups participated in a free sorting and verbalisation tasks. Additionally, a descriptive profiling was performed by the trained group. Both the groups distinguished the samples according to their umami compounds levels, although only the trained panellists recognised the taste increase as umami and provided a classification of the samples closer to formulation’s differences. The untrained subjects distinguished the soup samples for flavour intensification, although they did not recognise the ingredients responsible for enhancing the flavour.

Prolonged expression and production of Staphylococcus aureus enterotoxin A in processed pork meat

The bacteriophage-encoded staphylococcal enterotoxin A (SEA) is the toxin most frequently reported to be involved in staphylococcal food poisoning. In this study, sea expression and SEA formation were studied in four processed pork products: boiled ham, hot-smoked ham, Serrano ham (dry-cured Spanish ham) and black pepper salami. The products were selected because of their differences in intrinsic factors. As a reference, Staphylococcus aureus was cultivated under favorable planktonic growth conditions. Expression was mainly linked to bacterial growth for both meat products and broth cultures. In liquid broth, however, the relative level of sea mRNA peaked in the late exponential phase and then rapidly declined, while in the meat products allowing immediate growth, i.e. boiled and smoked ham, active sea expression occurred throughout the incubation period of seven days. Lower levels of sea mRNA and SEA were found in smoked ham compared to boiled ham, although viable counts of S. aureus on the two products were similar. Furthermore, the SEA concentration in the boiled ham reached a maximum after three days of incubation and then unpredictably decreased. In the Serrano ham, no increase in cell number was observed until day seven, and sea expression and extracellular SEA could only be detected on days five and seven. Finally, the black pepper salami with low pH and competing microbiota proved to be a difficult environment for the survival of S. aureus. The molecular mechanism behind the behaviour of S. aureus SEA expression is discussed in connection to the life-cycle of the SEA-encoding bacteriophage and the microbial communities in these pork products.

Inhibition of Staphylococcus aureus in broth and meat broth using synergies of phenolics and organic acids

This study assessed the occurrence of an enhancing inhibitory effect of the combined application of thymol and carvacrol with lactic and acetic acid against Staphylococcus aureus using the determination of Fractional Inhibitory Concentration (FIC) index and kill-time assay in meat broth and in a food model (meat). Minimum Inhibitory Concentration (MIC) of carvacrol and thymol were 1.25 and 0.6 µL/mL, respectively. FIC indices of the combined application of the phenolic constituents and organic acids were 0.5 suggesting a synergic interaction. No difference ( p > 0.05) was found among the bacterial counts for the meat broth added of the phenolics alone or in combination with lactic acid at sub-inhibitory concentrations. Contrarily, the bacterial counts found for the meat broth added of the phenolics alone were significantly lower ( p < 0.05) than the counts obtained for the broth added of the combination of phenolics and acetic acid. No difference ( p > 0.05) was found among the bacterial counts for the meat model added of phytochemicals alone and in combination with the organic acids. The tested antimicrobials alone or in mixture provided smaller anti-staphylococcal effect in meat broth than in meat model. These results could arise as an interesting approach for the improvement of food preservation using more natural procedures, considering the current demand of consumer and sensory quality of foods.

Molecular characterization of biofilm formation and attachment of Salmonella enterica serovar typhimurium DT104 on food contact surfaces.

The molecular mechanism of biofilm formation by Salmonella Typhimuriun DT104 was characterized for a better understanding of its attachment and colonization in food processing environments. A library of random mutagenized clones was screened for phenotypic analyses of their ability to form biofilm, pellicle, curli, and cellulose. The genes identified were involved in lipopolysaccharide synthesis, assembly of flagella, regulation of rRNA biosynthesis, and outer membrane transportation and signaling. The insertion of transposon in flgK, rfbA, nusB, and pnp genes resulted in decreased biofilm formation. Alterations of flagellar and lipopolysaccharide production were confirmed in the flgK mutant and rfbA mutant, respectively. Biofilm formation by these four mutants in meat and poultry broths and their attachment on surfaces of stainless steel and glass were significantly reduced compared with those of the wild-type strain (P < 0.05). On the contrary, the mutation of STM4263 and yjcC genes in Salmonella Typhimuriun DT104 resulted in increased biofilm formation and attachment of the species in tested broths and on contact surfaces. Our findings suggest that many factors, such as production of exopolymeric substances and their efficient transportation through outer membrane, expression of flagella, and regulation of exoribonucleases and RNA-binding protein, could be involved in biofilm formation and attachment of Salmonella Typhimurium DT104 on contact surfaces.

Biofilm evidence and the microbial diversity of horse wounds

Evidence of biofilms in human chronic wounds are thought to be responsible for preventing healing in a timely manner. However, biofilm evidence in horse wounds has not yet been documented. Consequently, this study aimed to determine whether biofilms could be detected in wounds, and to investigate the microbiology of chronic wounds in horses. Prior to analysis, wound surfaces were irrigated with 5 mL of sterile saline to remove debris. All wounds were swabbed twice (1 cm2 area) using sterile cotton-tipped swabs. In addition to this, 2 tissue biopsies were taken to investigate evidence of biofilm and the microbiology richness of the wounds. All swabs and 1 biopsy sample were transported to the laboratory in Robertson's cooked meat broth. Traditional culturable techniques and denaturing gradient gel electrophoresis with PCR were utilized to identify common bacteria isolated in all wounds. Following analysis of a number of the biopsy samples, biofilms could be clearly seen. The most common bacteria isolated from each wound analysed included Pseudomonas aeruginosa, Staphylococcus epidermidis, Serratia marcescens, Enterococcus faecalis, and Providencia rettgeri. Sequencing of the 16S ribosmonal DNAs, selected on the basis of DGGE profiling, enabled identification of bacterial species not identified using culturable technology. This study is the first to identify biofilms in the chronic wounds of horses. In addition, this study also demonstrated the importance of combining DGGE-PCR with culture techniques to provide better microbiology analysis of chronic wounds.

Combined application of origanum vulgare l. essential oil and acetic acid for controlling the growth of staphylococcus aureus in foods.

This study evaluated the occurrence of an enhancing inhibitory effect of the combined application of Origanum vulgare L. essential oil and acetic acid against Staphylococcus aureus by the determination of Fractional Inhibitory Concentration (FIC) index and kill-time assay in nutrient broth, meat broth and in a food model (meat pieces). Acetic acid showed MIC and MFC of 0.6 and 1.25 μL.mL-1, respectively. For O. vulgare essential oil MIC and MBC were 1.25 and 2.5 μL.mL-1, respectively. FIC indexes of the mixture of essential oil and acetic acid at MIC x ½ were ≤ 1.0, showing an additive effect. No synergy was found at kill-time study. Anti-staphylococcal effect of the antimicrobials alone or in mixture (MIC x ½) was lower in meat than in nutrient and meat broths. The effective combination of essential oils and organic acids could appear as an attractive alternative for the food industry, as the doses to inhibit the microbial growth in foods can be lowered.

Modelling the effect of temperature, carbon dioxide, water activity and pH on growth and histamine formation by Morganella psychrotolerans

A mathematical model was developed to predict growth and histamine formation by Morganella psychrotolerans depending on temperature (0–20 °C), atmosphere (0–100% CO 2), NaCl (0.0–6.0%) and pH (5.4–6.5). Data from experiments with both sterile tuna meat and Luria Bertani broth was used to develop the mathematical growth and histamine formation model. The expanded Logistic model with a growth dampening parameter ( m) of 0.7 was used as primary growth model. A primary model for histamine formation during storage was obtained by combining the expanded Logistic growth model with a yield factor ( Y His/CFU). 120 maximum specific growth rate ( µ max)-values were generated for M. psychrotolerans and used to model the combined effect of the studied environmental parameters. A simple cardinal parameter type secondary model was used to model the effect of the four parameters on µ max. The maximum population density (log N max) was correlated with log ( Y His/CFU) and a simple constrained polynomial (quadratic) secondary model was developed for the effect of the environmental conditions on these model parameters. The developed model describes the effect of initial cell concentrations, storage conditions and product characteristics on histamine formation. This is a significant progress compared to previously available models for the effect of storage temperature only.

Cooking activities during the Middle Ages: organic residues in ceramic vessels from the Sant'Antimo Church (Piombino–Central Italy)

A combined gas chromatography-electron ionization (GC-EI), atmospheric pressure chemical ionization (APCI) mass spectrometry (MS) and MS/MS approach has been used for characterizing organic residues of ceramic vessels of different forms and dimensions recovered from a vault of the apse of the 13th century church of Sant'Antimo in Piombino (Central Italy). The artifacts studied in this investigation are pots, jugs, colanders and pans probably used for cooking meals or as food containers. GC-MS has shown the presence of different fatty acids and other nonpolar markers, while APCI ionization proved to be particularly useful in the detection of diterpenoids and diacylglycerols. The data show that some organic markers may be of animal origin, while others are typical constituents or biodegradation products of vegetables. This allows one to propose the main use of these articles as vessels for cooking meat and maybe vegetable broths and soups. As there is no strict correlation between organic markers and shape, form and dimension of the ceramic vessel, it appears that the different objects probably served the same function. Chemical characterization of the organic residues of ceramic vessels, together with all the other archaeological data, contributes to a better understanding of their uses and the customs of people in the Middle Ages in Central Italy.

Modelling microbial growth in meat broth with added lactic acid under refrigerated storage

SummaryLactic acid is a classical preservative in meat industry and it is used with high efficiency on sanitization of meat surfaces. This work analyses the effect of temperature and added lactic acid on the growth of different beef muscle‐isolated bacteria: Pseudomonas sp. and two enterobacteria identified as Klebsiella sp. and Escherichia coli, in a liquid model system. Inoculation levels between 104 and 106 CFU mL−1 in a culture medium of meat extract broth at 2% were studied, with addition of lactic acid in concentrations of 0.29, 0.39 and 0.58 m, which allowed to reach pH values of 6.1, 5.8 and 5.6 respectively. Culture media inoculated with each micro‐organism were incubated at three temperatures: 0, 4 and 10 °C in aerobiosis; bacterial counts as a function of time were mathematically modelled by applying Gompertz equation. Derived parameters: lag phase (LPD), specific growth rate (μ) and maximum population density were calculated. When the observed effect was bacteriostactic a linear regression was used. Results were compared with a meat extract broth control at pH = 7. At 10 °C added lactic acid produced a higher variation in μ values for Klebsiella sp. and E. coli, whereas LPD values were modified between six and three times for each micro‐organism. The highest LPD values were observed for E. coli, followed by Pseudomonas and finally by Klebsiella. LPD values for E. coli at 0 °C ranged between 40 and 50 days, whereas at 10 °C they varied between 3 and 6.5 days. Escherichia coli did not grow at 0 °C, except when the control system was at pH 7. The effect of temperature on μ values was modelled through an Arrhenius type equation and the corresponding activation energies were determined; μ and LPD values were correlated with the undissociated acid concentration for the three tested temperatures.

Aceitabilidade de flocos desidratados de abóbora

OBJETIVO: Avaliar a aceitabilidade de flocos desidratados de abóbora, uma vez que tal produto pode constituir uma alternativa no combate à hipovitaminose A. MÉTODOS: Os flocos foram avaliados quanto às características microbiológicas, por meio das análises de coliformes a 45ºC, Escherichia coli, Staphylococcus aureus, Salmonela sp, contagem de bolores e leveduras, e características físico-químicas, por meio da análise de umidade, proteínas, lipídios, cinzas, fibra alimentar, carboidratos, carotenóides, estabilidade ao longo do tempo de armazenamento e aceitabilidade dos flocos adicionados ao feijão e ao pirão de 188 adultos e 67 crianças, respectivamente. RESULTADOS: Os flocos estavam adequados quanto às características microbiológicas e físico-químicas e os percentuais de aceitação de 95,21% para os adultos e 95,52% para as crianças. CONCLUSÃO: Os flocos desidratados de abóbora podem ser utilizados em larga escala para o estudo do efeito deste produto no combate à hipovitaminose A.

Inhibition of Clostridium perfringens LMG 11264 in Meat Samples of Chicken Turkey and Beef by the Bacteriocin Plantaricin UG1

The inhibition of Clostridium perfringens LMG 11264 (Cl. perfringens) by the bacteriocin plantaricin UG1 in vit ro (brain heart infusion broth and cooked meat broth) and in meat samples (cooked meat, uncooked meat & dry mortadella) of poultry (chicken and turkey) and beef was studied. The inhibitory activity of plantaricin UG1 was apparently more in liquid systems (BHI broth & cooked meat broth) than in mea t samples. The viable cells of Cl. perfringens were increased from 10 cfu/gm to 10 - 10 cfu/gm in almost 5 7 9