Microbiological Quality of Fresh Produce and Ready-to-Eat Salads Through the Processing Line at a Mass Catering System

Yıl 2025, Cilt: 18 Sayı: 2, 173 - 181, 31.12.2025

Ergün Ömer Göksoy , Yıldız Ay Yiğit , Pelin Koçak Kızanlık , Cemil Şahiner

https://doi.org/10.47027/duvetfd.1655386

https://izlik.org/JA89ZZ54RN

Öz

This study investigated the microbiological load of vegetables used for salad preparation through the salad processing line of a mass catering establishment and salad as a final product. Total viable count (TVC), the levels of total coliform bacteria and Staphylococcus aureus (S. aureus), and the presence of Eschericia coli (E. coli) in the salads a long with the processing line were determined. A total of 510 vegetable and salad samples, and 30 washing water samples (before and after washing) were collected and analyzed. The results showed that the TVCs were ranging between 5.54 log cfu/g and 6.66 log cfu/g on the fresh produce entering kitchen. The total coliform bacteria levels were between 3.31 log cfu/g and 5.98 log cfu/g. The levels of S. aureus obtained from vegetables just before processing were between 2.10 log cfu/g and 4.91 log cfu/g. The incidence of E. coli was ranging between 10 and 30%. In salads, the levels for TVC, total coliform bacteria and S. aureus were 5.36 log cfu/g, 4.72 log cfu/g and 2.67 log cfu/g, respectively. The incidence of E. coli was 30%. The levels of bacteria examined and the incidence of E. coli in salads were found to be substantially high and cross contamination was present through the steps of salad processing line. It is thought that the results of this study may help the establishments to reduce cross contamination at the processing steps and potential public health hazards.

Anahtar Kelimeler

Foodborne microorganisms , food preservation and processing , food safety and quality , fresh-cut fruit and vegetables , salad.

Etik Beyan

The authors declare that this study does not require the ethical statement.

Destekleyen Kurum

This study was supported by Aydın Adnan Menderes University Scientific Research Project Coordination (Project Number: VTF-15020).

Proje Numarası

VTF-15020

Teşekkür

The authors thank Prof. Dr. H. Erbay Bardakcioglu for conducting the statistical analyses of the work presented here.

Toplu Tüketim Merkezlerinde Salatalık Sebzelerin ve Tüketime Hazır Salataların Üretim Hattı Boyunca Mikrobiyolojik Kaliteleri

https://izlik.org/JA89ZZ54RN

Öz

Bu çalışmada bir toplu tüketim işletmesi için salata hazırlama sürecinde üretim basamaklarında kullanılan sebzelerin ve son ürün olan salatanın mikrobiyolojik kalitesi araştırılmıştır. Toplam mezofil aerobik canlı sayısı (TMAC), toplam kolifom bakteri ve Staphylococcus aureus (S. aureus) seviyeleri ile hazırlama süreci boyunca üretim basamaklarındaki Eschericia coli (E. coli) varlığı tespit edilmiştir. Çalışma kapsamında toplam 510 adet sebze ve salata örneği ile 30 adet yıkama suyu örneği (yıkama öncesi ve sonrası) analiz edilmiştir. Sonuçlar mutfağa giren taze ürünlerin TMAC sayılarının 5,54 log kob/g ile 6,66 log kob/g arasında değiştiğini göstermiştir. Toplam koliform bakteri seviyeleri 3,31 log kob/g ile 5,98 log kob/g arasında bulunmuştur. İşlemeden hemen önce sebze örneklerinden elde edilen S. aureus seviyeleri 2,10 log kob/g ile 4,91 log kob/g arasında bulunmuştur. Taze sebze örneklerinde E. coli’nin bulunma oranı ise %10 ile %30 arasında belirlenmiştir. Salatalarda TMAC sayısı, toplam koliform bakteri ve S. aureus seviyeleri sırasıyla 5,36 log kob/g, 4,72 log kob/g ve 2,67 log kob/g olarak tespit edilmiştir. Salata örneklerinde E. coli bulunma oranının ise %30 olduğu gözlemlenmiştir. Araştırmada bir toplu yemek işletmesinin salata işleme hattında salatalarda incelenen bakterilerin mikrobiyolojik yükü ile E. coli varlığının oldukça yüksek olduğu ve işleme hattında çapraz kontaminasyonun mevcut olduğu bulunmuştur. Bu çalışmanın sonuçlarının, işletmelere çapraz kontaminasyonu ve olası halk sağlığı tehlikelerini azaltmada yardımcı olabileceği düşünülmektedir.

Anahtar Kelimeler

Gıda kaynaklı mikroorganizmalar , gıda güvenliği ve kalitesi , gıda muhafazası ve işlenmesi , salata , taze kesilmiş meyve ve sebzeler

Proje Numarası

VTF-15020

Kaynakça

• Rekhy R, McConchie R (2014). Promoting consumption of fruit and vegetables for better health. Have campaigns delivered on the goals? Appetite, 79:113-123.
• Wang X, Ouyang Y, Liu J, et al. (2014). Fruit and vegetable consumption and mortality from all causes, cardiovascular disease, and cancer: systematic review and dose-response meta-analysis of prospective cohort studies. BMJ, 349:g4490.
• Abadias M, Usall J, Anguera M, Solson C, Vinas I (2008). Microbiological quality of fresh, minimally-processed fruit and vegetables, and sprouts from retail establishments. Int J Food Microbiol., 123:121-129.
• Eurostat (2018). Fruit and vegetable consumption statistics - statistics Explained. Ec. europa.eu. Retrieved 27 January 2022, from https://ec.europa.eu/eurostat/statistics-explained/index.php/Fruit_and_vegetable_consumption_statistics#Genera l_overvie.
• Mir SA, Shah M.A, Mir MM, Dar BN, Greiner R, Roohinejad S (2018). Microbiological contamination of ready-to-eat vegetable salads in developing countries and potential solutions in the supply chain to control microbial pathogens. Food Control, 85:235-244.
• Callejon RM, Rodríguez-Naranjo MI, Ubeda C, Hornedo-Ortega R, Garcia-Parrilla MC, Troncoso AM (2015). Reported foodborne outbreaks due to fresh produce in the United States and European Union: trends and causes. Foodborne Pathog Dis., 12:32-38.
• Carstens CK, Salazar JK, Darkoh C (2019). Multistate outbreaks of foodborne illness in the United States associated with fresh produce from 2010 to 2017. Front Microbiol., 10:2667.
• FAO/WHO (2008). Microbiological hazards in fresh leafy vegetables and herbs: Meeting report. Microbiological risk assessment series (pp. 163). Rome, Italy Food Agriculture Organization of the United Nations/ World Health Organization. https://www.who.int/foodsafety/publications/micro/MRA_14_JEMRA.pdf. Last Access 28.03.2022.
• Aworh OC (2021). Food safety issues in fresh produce supply chain with particular reference to sub-Saharan Africa. Food Control, 123:107737.
• CDC (2022a). Centers for Disases Control and Prevention. National Outbreak Reporting System (NORS) https://wwwn.cdc.gov/norsdashboard/. Last access, 01.02.2022.
• CDC (2022b). Centers for Disases Control and Prevention. CDC Current Outbreak List. https://www.cdc.gov/outbreaks/index.html. Last access, 01.02.2022.
• EFSA (2008). European Food Safety Authority. Scientific opinion of the panel on biological hazards on a request from the European Food Safety Authority on foodborne antimicrobial resistance as a biological hazard. EFSA J., 765: 1–87.
• EFSA (2012). European Food Safety Authority. European Food Safety Authority and European Centre for Disease Prevention and Control; The European Union Summary Report on antimicrobial resistance in zoonotic and indicator bacteria from humans, animals and food in 2010. EFSA J., 10(3): 2598 (http://www.efsa.europa.eu/en/ efsajournal/doc/2598.pdf).
• Campos J, Mourão J, Pestana N, Peixe L, Novais C, Antunes P (2013). Microbiological quality of ready-to-eat salads: An underestimated vehicle of bacteria and clinically relevant antibiotic resistance genes. Int J Food Microbiol, 166:464–470.
• DANMAP (2018). Danish Integrated Antimicrobial Resistance Monitoring, Research Programme. Use of antimicrobial agents and occurrence of antimicrobial resistance in bacteria from food animals, food and humans in Denmark. Statens Serum Institut National Food Institute, Technical University of Denmark. https://www.danmap.org › sites › downloads › reports, Last access 25.03.2022.
• Rahman M, Alam MU, Luies SK, et al. (2022). Contamination of fresh produce with antibiotic resistant bacteria and associated risks to human health: A Scoping Review. Int J Environ Res Public Health., 19:360.
• Faour-Klingbeil D, Murtada M, Kuri V, Todd EC (2016). Understanding the routes of contamination of ready-to-eat vegetables in the Middle East. Food Control, 62:125-133.
• Castro-Ibanez I, Gil MI, Allende A (2017). Ready-to-eat vegetables: Current problems and potential solutions to reduce microbial risk in the production chain. LWT-Food Sci Tech., 85:284-292.
• Johnston LM, Jaykus L, Moll D et al. (2005). A field study of the microbiological quality of fresh produce. J Food Prot, 68:1840-1847.
• Holvoet K, De Keuckelaere A, Sampers I, Van Haute S, Stals A, Uyttendaele M (2014). Quantitative study of cross-contamination with Escherichia coli, E. coli O157, MS2 phage and murine norovirus in a simulated fresh-cut lettuce wash process. Food Control, 37:218-227.
• Lehto M, Kuisma R, Määttä J, Kymäläinen HR, Mäki M (2011). Hygienic level and surface contamination in fresh-cut vegetable production plants. Food Control, 22:469-475.
• Sodha SV, Lynch M, Wannemuehler K, et al. (2011). Multistate outbreak of Escherichia coli O157:H7 infections associated with a national fast-food chain, 2006: a study incorporating epidemiological and food source traceback results. Epidemiol Infect., 139: 309–316.
• Bencardino D, Amagliani G, Brandi G (2021). Carriage of Staphylococcus aureus among food handlers: An ongoing challenge in public health. Food Control, 130:108362.
• Derrick J, Hollinghurst P, O’Brien S, Elviss N, Allen DJ, Iturriza-Gomara M (2021). Measuring transfer of human norovirus during sandwich production: Simulating the role of food, food handlers and the environment. Int J Food Microbiol., 348:109151.
• Huang K, Yi J, Young MG, Nitin N (2022). Cell-based carriers incorporated antimicrobial coatings on diverse food contact surfaces for preventing cross-contamination of fresh produce. Food Control, 134:108700.
• ISO 4833-2 (2013). Microbiology of the food chain - Horizontal method for the enumeration of microorganisms - Part 2: Colony count at 30 degrees C by the surface plating technique. International Standard 2013, Geneva, Switzerland. [Retrieved February 19, 2021]. https://www.iso.org/standard/29824.html
• ISO 6888-1 (2021). Microbiology of food and animal feeding stuffs: horizontal method for the enumeration of coagulase positive staphylococci (Staphylococcus aureus and other species). Part 1: technique using Baird Parker agar medium. International Standard 2021, Geneva, Switzerland.
• ISO 4832 (2010). Microbiology of food and animal feeding stuffs - Horizontal method for the enumeration of coliforms - Colony-count technique. International Standard 2001, Geneva, Switzerland.
• ISO 16649-2 (2001). Microbiology of food and animal feeding stuffs — Horizontal method for the enumeration of beta-glucuronidase-positive Escherichia coli Part 2: Colony-count technique at 44 degrees C using 5-bromo-4-chloro-3-indolyl beta-D-glucuronide. International Standard 2001, Geneva, Switzerland.
• Meldrum RJ, Little CL, Sagoo S, Mithani V, McLauchlin J, De Pinna E (2009). Assessment of the microbiological safety of salad vegetables and sauces from kebab take-away restaurants in the United Kingdom. Food Microbiol., 26(6):573–577.
• Younus MI, Sabuj AAM, Haque ZF, et al. (2020). Microbial risk assessment of ready-to-eat mixed vegetable salads from different restaurants of Bangladesh Agricultural University campus. J Adv Vet Anim Res., 7(1): 34–41.
• Stephan R, Althaus D, Kiefer S, et al (2015). Foodborne transmission of Listeria monocytogenes via ready-to eat salad: A nationwide outbreak in Switzerland, 2013-2014. Food Control, 57:14-17.
• Murray K, Wu F, Shi J, Xue SJ, Warriner K (2017). Challenges in the microbiological food safety of fresh produce: Limitations of post-harvestwashing and the need for alternative interventions Food Qual Saf., 2017, 1(4), 289–301.
• Alegbeleye OO, Singleton I, Sant'Ana AS (2018). Sources and contamination routes of microbial pathogens to fresh produce during field cultivation: A review. Food Microbiol.,73: 177–208.
• Balali GI, Yar DD, Dela VGA, Adjei-Kusi P (2020). Microbial contamination, an increasing threat to the consumption of fresh fruits and vegetables in today’s world. Int J Food Microbiol., 3029295.
• Zhu Y, Wu F, Trmcic A, Wang S, Warriner K (2020). Microbiological status of reusable plastic containers in commercial grower/packer operations and risk of Salmonella cross-contamination between containers and cucumbers. Food Control, 110, 107021.
• Rodriguez-Caturla MY, Valero A, Carrasco E, Posada GD, Garcia-Gimeno RM, Zurera G (2012). Evaluation of hygiene practices and microbiological status of ready-to-eat vegetable salads in Spanish school canteens. J Sci Food Agric., 92: 2332–2340
• Calonico C, Delfino V, Pesavento G, Mundo M, Lo Nostro A (2019). Microbiological quality of ready-to-eat salads from processing plant to the consumers. J Food Nut Res., 2019, Vol. 7, No. 6, 427-434.
• Seow J, Ágoston R, Phua L, Yuk HG (2012). Microbiological quality of fresh vegetables and fruits sold in Singapore. Food Control, 25:39-44.
• Aycicek H, Oguz U, Karci K (2006). Determination of total aerobic and indi-cator bacteria on some raw eaten vegetables from wholesalers in Ankara, Turkey. Int J Hyg Environ., 209(2):197–201.
• Regulation concerning water intended for human consumption. Official Gazette of Publication: 07.03.2013. Nr. 28580.
• Warriner K, Huber A, Namvar A, Fan W, Dunfield K (2009). Recent advances in the microbial safety of fresh fruits and vegetables. Ad Food Nutr Res., 57: 155-208.
• Whipps JM, Hand P, Pink DA, Bending GD (2008). Human pathogens and the phyllosphere. Adv Appl Microbiol., 64:183-221.
• Beuchat LR (1998). Surface decontamination of fruits and vegetables eaten raw: a review. WHO/FSF/FOS/98.2. Food Safety Unit. World Health Organization. https://apps.who.int/iris/bitstream/handle/10665/64435/WHO_FSF_FOS_98.2.pdf?sequence=1&isAllowed=y. Last access 25.03.2022.
• Shen C, Geornaras I, Kendall PA, Sofos JN (2009). Antilisterial activities of salad dressings, without or with prior microwave oven heating, on frankfurters during simulated home storage. Int J Food Microbiol., 132(1):9-13.
• Yang H, Kendall PA, Medeiros L, Sofos JN (2009). Inactivation of Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella Typhimurium with compounds available in households. J Food Prot., 72(6):1201-1208.
• Beuchat S, Klaibe R, Hua W, Hammes WP, Carle R (2003). Effect of temperature and chlorination on pre-washing water on shelf-life and physiological properties of ready-to-use iceberg lettuce. IFSET., 6(2):171-182.
• Nastou A, Rhoades J, Smirniotis P, Makri I, Kontominas M, Likotrafiti E (2012). Efficacy of household washing treatments for the control of Listeria monocytogenes on salad vegetables. Int J Food Microbiol., 159:247–253.
• López-Gálvez F, Tudela JA, Allende A, Gil MI (2019). Microbial and chemical characterization of commercial washing lines of fresh produce highlights the need for process water control. Innov Food Sci Emerg., 51:211–219.
• Erickson MC, Liao J, Cannon JL, Ortega YR (2015). Role of brushes and peelers in removal of Escherichia coli O157:H7 and Salmonella from produce in domestic kitchens. J Food Protect., 78(9):1624–1631.
• Nguz K, Shindano J, Samapundo S, Huyghebaert A (2005). Microbiological evaluation of fresh-cut vegetables produced in Zambia. Food Control, 16:623-628.
• Seo YH, Jang JH, Moon KW (2010). Microbial evaluation of minimally processed vegetables and sprouts produced in Seoul, Korea. Food Sci Biotechnol., 19(5):1283-1288.
• Najafi MBH, Bahreini M (2012). Microbiological Quality of Mixed Fresh-Cut Vegetable Salads and Mixed Ready-to-Eat Fresh Herbs in Mashhad, Iran. 2012 International Conference on Nutrition and Food Sciences IPCBEE vol. 39 (2012) IACSIT Press, Singapore.
• Akyea-Mensah E., Kortei NK, Aboagye G, Tuah B, Annan T, Madilo FK, Adu-Bobi NAK, Annan SNY, Armah JO, Edziah FS (2025). Microbial quality of some street-vended and restaurant vegetable salads in the Ho municipality of Ghana. Discov Environ., 3(1):1-16.
• Zernadji W, Rahmani F, Jebri S, Hamdi M, Khammassi M, Dhib S, Hmaied F (2025). Distribution of microbial contaminants of minimally processed salads produced in Tunisia: Need to strengthen good hygiene practices. Int J Food Sci., 2025(1):9570620.
• McLauchlin J, Aird H, Amar CFL, Jenkins C, Jørgensen F, Lai S, Willis C (2022). Microbiological quality of ready-to-eat salad products collected from retail and catering settings in England during 2020 to 2021. J. Food Prot., 85(12):1680-1689.
• Soriano JM, Rico H, Molto JC, Manes J (2000). Assessment of the microbiological quality and wash treatments of lettuce served in university restaurants. Int J Food Microbiol., 58:123-128.
• Viswanathan P, Kaur R (2001). Prevalence and growth of pathogens on salad vegetables, fruits and sprouts. Int J Hyg Environ Health., 203:205-213.