Sanitation of liquid egg products by nonthermal processes: HACCP and inactivation studies

3rd Seminar on Risk Management by Hygienic Design and Efficient Sanitation Programs; Tallinn; Estonia; 4 May 2009 through 6 May 2009Foodborne disease outbreaks involving Escherichia coli O157:H7 and Salmonella enteriditis in liquid egg products (LEPs) are the major public health concern. Egg is a principal source of the S. enteritidis able to colonize the ovarian tissue and is present within the contents of intact shell eggs. Most of the S. enteritidis outbreaks have been associated with shell eggs or egg containing products. Although statutory action has been taken at breeding flock level, contaminated eggs and LEPs remain the main source of infection. The special facility of S. enteritidis to cause prolonged infection of the avian reproductive tract has been a major factor in vertical transmission of the organism from breeding flocks and internal contamination of eggs is thought to have been the major factor in its spread S. enteritidis localizes in glandular parts of the reproductive tract

Effects of pomegranate and pomegranate-apple blend juices on the growth characteristics of Alicyclobacillus acidoterrestris DSM 3922 type strain vegetative cells and spores

The present study examined the growth characteristics of Alicyclobacillus acidoterrestris DSM 3922 vegetative cells and spores after inoculation into apple, pomegranate and pomegranate-apple blend juices (10, 20, 40 and 80%, v/v). Also, the effect of sporulation medium was tested using mineral [Bacillus acidoterrestris agar (BATA) and Bacillus acidocaldarius agar (BAA)] and non-mineral containing media [potato dextrose agar (PDA) and malt extract agar (MEA)]. The juice samples were inoculated separately with approximately 105CFU/mL cells or spores from different sporulation media and then incubated at 37°C for 336h. The number of cells decreased significantly with increasing pomegranate juice concentration in the blend juices and storage time (p<0.001). Based on the results, 3.17, 3.53, and 3.72 log cell reductions were observed in 40%, 80% blend and pomegranate juices, respectively while the cell counts attained approximately 7.17logCFU/mL in apple juice after 336h. On the other hand, the cell growth was inhibited for a certain time, and then the numbers started to increase after 72 and 144h in 10% and 20% blend juices, respectively. After 336h, total population among spores produced on PDA, BATA, BAA and MEA indicated 1.49, 1.65, 1.67, and 1.28 log reductions in pomegranate juice; and 1.51, 1.38, 1.40 and 1.16 log reductions in 80% blend juice, respectively. The inhibitory effects of 10%, 20% and 40% blend juices varied depending on the sporulation media used. The results obtained in this study suggested that pomegranate and pomegranate-apple blend juices could inhibit the growth of A. acidoterrestris DSM 3922 vegetative cells and spores

Quantitative risk assessment models for food pathogens

3rd Seminar on Risk Management by Hygienic Design and Efficient Sanitation Programs; Tallinn; Estonia; 4 May 2009 through 6 May 2009Risk assessment (RA) which is a holistic approach involves hazard identification, exposure assessment, dose-response assessment, and risk characterization (Oscar, 2004). Microbiological risk assessments (MRAs) have been subdivided into four steps, which comprise, hazard identification, hazard characterization, exposure assessment and risk characterization. RAs are well developed for chemical hazards, and much effort has been put into the application of this type analysis to microbial food safety risks, especially for human foodborne diseases. The methods used for MRA, as well as the underlying concepts for evaluating risk derived from foodborne organisms and the effects of control measures on reducing risk are still new to many countries including developing countries. It is important to demonstrate examples of practical data generation and modelling even if they are limited in data size

Short wave ultraviolet light (UVC) disinfection of surface - Inhibition of Alicyclobacillus acidoterrestris spores on agar medium

Risk Assessment of Microbial Problems and Preventive Actions in Food Industry - 2nd Open Seminar Arranged by SAFOODNET - Food Safety and Hygiene Networking Within New Member States and Associated Candidate Countries; Istanbul; Turkey; 22 October 2007 through 23 October 2007Alicyclobacillus species are thermoacidophilic spoilage spore-formers found in soil. The spores can survive the normal hot fill processes that are carried out on commercial fruit juices. It seems likely that fruit in contact with soil are susceptible to contamination by Alicyclobacillus. Beverage ingredients e.g. liquid sugar are also a potential contamination sources. Alicyclobacillus has also been isolated from citrus processing lines

Evaluation of bioactivity of pomegranate fruit extract against Alicyclobacillus acidoterrestris DSM 3922 vegetative cells and spores in apple juice

This research evaluated the antimicrobial activity of commercial pomegranate extract (POMELLA®, PE) against Alicyclobacillus acidoterrestris vegetative cells and spores (approximately 105 log CFU/mL) in apple juice (pH 3.82, °Brix 11.3) during storage at 37°C. After 240h, the cell counts were reduced from the initial log count (CFU/mL) by 2.84, 3.26, 3.32, 3.46 and 3.56 in the apple juice with PE at the concentrations of 2.5, 5, 10, 20 and 40μg/mL, respectively. On the other hand, counts of the control reached 7.36 log CFU/mL after 24h. The Weibull model satisfactorily described the survival curves of cell inactivation kinetics (R2 > 0.983). While the growth of all spores obtained from different sporulation media (potato dextrose agar, malt extract agar, Bacillus acidoterrestris agar, and Bacillus acidocaldarius agar) was inhibited in the apple juice with PE (2.5-40μg/mL), the control spores increased by 1.9-2.2 log CFU/mL after 336h. Based on the scanning electron microscopy (SEM) imaging, vegetative cells indicated substantial damage and spore germination was inhibited in the apple juice with PE. The results showed that PE can have possible uses as a natural antimicrobial to control the growth of A.acidoterrestris vegetative cells and spore germination in the apple juice. © 2015 Elsevier Ltd

The effect of sporulation medium on Alicyclobacillus acidoterrestris guaiacol production in apple juice

The present study evaluated the effect of sporulation medium on guaiacol formation from vanillin and vanillic acid by Alicyclobacillus acidoterrestris DSM 3922 in the reconstituted apple juice (pH 3.82, °Brix 11.3). For sporulation, potato dextrose agar and Bacillus acidoterrestris agar were used. After heat-activation, spores were turned into vegetative cells and inoculated into juice samples to a final concentration of 103 or 105 CFU/mL. Samples were incubated at 37 °C for 264 h and guaiacol concentration was determined using peroxidase enzyme colourimetric assay. Based on the results, the conversion of vanillic acid into guaiacol was faster than that of vanillin among both cell suspensions. Also, there were no significant differences among any of the samples inoculated into apple juice spiked with vanillin at the end of the incubation period (P > 0.05). In the case of vanillic acid, the guaiacol concentrations were significantly different among cells activated from spores produced on PDA and BATA (P < 0.05). The obtained results suggested that type of sporulation medium composition may affect the guaiacol concentration depending on inoculum level and type of precursor present in the apple juice

Microbial profile and bacterial characterisation of naturally debittered Hurma olives compared to non-debittered Erkence variety during ripening period

Naturally debittered Hurma olive is grown in a specific area in Karaburun peninsula in Turkey. It is characterised by its sweet taste and it differs from other varieties by losing its bitterness caused by phenolic compounds during its maturation period on the tree. Therefore, Hurma olive does not require any further debittering process to be served as table olive. This study was particularly interested in the comparison of the microbial profile of Hurma olive during its 8 weeks of maturation period in two subsequent harvest years and Erkence (not naturally debittered) olive. In addition, main bacterial profile of both Hurma and Erkence olives were isolated and identified. Aerobic mesophilic microorganism (AMM), lactic acid bacteria (LAB), Enterobacteriaceae, Pseudomonadaceae, Staphylococci, Micrococcaceae, yeasts and moulds (Y&Ms) were detected (counted and isolated) in the olive drupes during the maturation period. Isolated bacteria were identified as different spp. of Bacillaceae, Enterobacteriaceae, Micrococcoceae and Pseudomonadaceae.Scientific and Technical Research Council of Turkey (TUBITAK-TOVAG 110O780

Modeling inactivation kinetics of liquid egg white exposed to UV-C irradiation

The efficiency of UV-C irradiation as a non-thermal pasteurization process for liquid egg white (LEW) was investigated. LEW inoculated with Escherichia coli K-12 (ATCC 25253), pathogenic strain of Escherichia coli O157:H7 (NCTC12900) and Listeria innocua (NRRL B33314) were treated with UV light using a bench top collimated beam apparatus. Inoculated LEW samples were exposed to UV-C irradiation of known UV intensity of 1.314mW/cm2 and sample depth of 0.153cm for 0, 3 5, 7, 10, 13, 17 and 20min. The populations of E. coli K-12, E. coli O157:H7 and L. innocua were reduced after 20min of exposure by 0.896, 1.403 and 0.960logCFU respectively. Additionally, the inactivation data obtained for each strain suspended in LEW was correlated by using Weibull (2 parameter), Log-Linear (1 parameter), Hom (2 parameter) and modified Chick Watson (2 parameter) models. The inactivation kinetics of E. coli K-12, E. coli O157:H7 and L. innocua were best described by modified Chick Watson model with the smallest root mean squared error (RMSE) (R2≥0.92). © 2010 Elsevier B.V.TÜBİTAK Project No: TOVAG-104O210; Izmir Institute of Technology (IYTE-38

Risk management in production of egg-pasta

3rd Seminar on Risk Management by Hygienic Design and Efficient Sanitation Programs; Tallinn; Estonia; 4 May 2009 through 6 May 2009Pasta (Italian for "dough") is a generic term for Italian variants of noodles, food made from a dough of flour, water and/or eggs. The word can also denote dishes in which pasta products are the primary ingredient, served with sauce or seasonings. There are approximately 350 different shapes of pasta. Examples include spaghetti (solid, thin cylinders), maccheroni (tubes or hollow cylinders), fusilli (swirls), and lasagne (sheets). Two other noodles, gnocchi and spätzle, are sometimes considered pasta. They are both traditional in parts of Italy. Pasta is categorized in two basic styles: Dried and fresh

Bacterial foodborne pathogens of concern

Microbial Contaminants and Contamination Routes in Food Industry - 1st Open Seminar arranged by SAFOODNET; Espoo; Finland; 22 January 2007 through 23 January 2007A high level of protection of public health is one of the fundamental objectives of food law as laid down in regulations (EC) No 178/2002 and 852/2004. Throughout the European Union (EU) consumers are requiring the food industry to provide them with an increasing range of safe, nutritious and healthy foods of high sensory quality and increased shelf life. To meet the demand for healthier food of high sensory quality, the use of additives and preservatives is being reduced or eliminated and minimal processing techniques introduced. To increase food safety and quality considerable amount of time, effort and money has been spent to food safety control and management (ISO 22000:2005) systems including better packaging methods and improved new pathogen detection methods