Acta Univ. Agric. Silvic. Mendelianae Brun. 2018, 66(2), 365-369 | DOI: 10.11118/actaun201866020365

Evaluation of Yoghurts with Thyme, Thyme Essential Oil and Salt

Viera Ducková, Miroslav Kročko, Vladimíra Kňazovická, Margita Čanigová
Department of Animal Products Evaluation and Processing, Faculty of Biotechnology and Food Sciences, Slovak University of Agriculture, Tr. A. Hlinku 2, 949 76 Nitra, Slovakia

The aim of this work was production and evaluation of yoghurts with different addition of thyme (Thymus vulgaris), thyme essential oil (EO) and salt. It was produced: control yoghurt, yoghurt with 0.45 % of salt and 0.25 % of thyme, yoghurt with 0.90 % of salt and 0.50 % of thyme, yoghurt with 0.45 % of salt and 0.004 % of thyme EO, yoghurt with 0.90 % of salt and 0.008 % of thyme EO. The time of yoghurt fermentation was extended from the previous 3.5 hours (control sample) to 5 hours for samples with thyme or even up to 7 hours for samples with thyme EO. The fermentation time also depended on the concentration of the used substances. The average titratable acidity of yoghurts fluctuated from 46.52 °SH to 49.51 °SH at day after the production and from 51.57 °SH to 55.75 °SH after 7 days of storage. Average pH values of yoghurts fluctuated from pH 4.77 to pH 4.81 at day after production and from pH 4.48 to pH 4.63 after storage. In all samples of yoghurts were not detected coliform bacteria (< 10 CFU.g-1). The yeasts were appeared rarely (101 CFU.g-1), and their numbers were increased during cold storage (102 up to 103 CFU.g-1). Moulds appeared rarely (101 CFU.g-1). The number of lactic acid bacteria reached required minimum value of 107 CFU.g-1. Samples of yoghurts reached characteristic yoghurt and thyme aroma. The intensity of sour, salty and thyme taste, determined by sensory evaluation was in experimental samples of yoghurts at different level. A higher concentration of thyme and thyme EO gave to yoghurts a bitter taste. The dense consistency of the yoghurts was decreased with the increased addition of thyme and thyme EO. According to results, we recommend the recipe of yogurt with 0.45 % of salt and 0.25 % of thyme or 0.004 % of thyme EO.

Keywords: yoghurt, essential oil, thyme

Published: May 2, 2018  Show citation

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Ducková, V., Kročko, M., Kňazovická, V., & Čanigová, M. (2018). Evaluation of Yoghurts with Thyme, Thyme Essential Oil and Salt. Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis66(2), 365-369. doi: 10.11118/actaun201866020365
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References

  1. BEHRAD, S., YUSOF, M. Y., GOH, K. L. and BABA, A. S. 2012. Manipulation of Probiotics Fermentation of Yogurt by Cinnamon and Licorice: Effects on Yogurt Formation and Inhibition of Helicobacter Pylori Growth in vitro. International Journal of Biological and Life Sciences, 8(3): 135-139.
  2. BURT, S. 2004. Essential oils: their antibacterial properties and potential aplications in food - review. Journal of Food Microbiology, 94(3): 223-253. DOI: 10.1016/j.ijfoodmicro.2004.03.022 Go to original source...
  3. CARVALHO, R. J., SOUZA, G. T., HONÓRIO, V. G., SOUSA, J. P, CONCEICAO, M. L. and MAGANANI, M. 2015. Comparative inhibitory effect of Thymus vulgaris L. essential oil against Staphylococcus aureus, Listeria monocytogenes and mesophilic starter co-culture in cheese-mimicking models. Food Microbiology, 52: 59-65. DOI: 10.1016/j.fm.2015.07.003 Go to original source...
  4. CVAK, Z., PETERKOVÁ, Ľ. and ČERNÁ, E. 1992. Chemické a fyzikálně-chemické metódy v kontrole jakosti mléka a mlékarenských výrobků. Praha: VÚPP.
  5. EL-NAWAWY, M. A., EL-KENANY, Y. M. and ABD EL-GHAFFAR, E. A. 1998. Effect of some herb plants on the use of yoghurt culture. In: Annals of agriculture Sci. 7th Conf. Agric. De. Res. Fac. Agric. Ain Shams University of Cairo, Egypt, 15-17 December.
  6. ERSÖZ, E., KINIK, O., YERLIKAYA, O. and MERVE, A. 2011. Effect of phenolic compounds on characteristics of strained yoghurts produced from sheep milk. African Journal of Agricultural Research, 6(23): 5351-5359.
  7. HAYALOGLU, A. A. and KARAGUL-YUCEER, Y. 2011. Utilization and characterization of small ruminants'milk and milk products in Turkey: Current status and new perspectives. Small Ruminant Research, 101(1-3): 73-83. DOI: 10.1016/j.smallrumres.2011.09.027 Go to original source...
  8. HOLLEY, R. A. and PATEL, D. 2005. Improvement in shelf-life and safety of perishable foods by plants essential oils and smoke antimicrobials. Food Microbiology, 22(4): 273-292. DOI: 10.1016/j.fm.2004.08.006 Go to original source...
  9. ISMAIL, A. M., HARBY, S. and SALEM, A. S. 2006. Production of flavored labneh with extended shelf life. Egyptian Journal of Dairy Science, 34: 59-68.
  10. MAHMOUDI, R., ZARE, P., HASSANZADEH, P. and NOSRATPOUR, S. 2014. Effect of Teucrium polium essential oil on the physicochemical and sensory properties of probiotic yoghurt. Journal of Food Processing and Preservation, 38(3): 880-888. DOI: 10.1111/jfpp.12042 Go to original source...
  11. OTAIBI, M. A. and DEMERDASH, H. E. 2008. Improvement of the quality and shelf life of concentrated yoghurt (labneh) by the adittion of some essential oils. African Journal of Microbiology Research, 2: 156-161.
  12. SHAHBAZI, Y. 2015. Ziziphora clinopodioides Essential Oil and Nisin as Pontential Antimicrobial Agents against Esherichia coli O157:H7 in Doogh (Iranian Yoghurt Drink). Journal of Pathogen, 2015: 176024. Go to original source...
  13. SHAHDADI, F., MIRZAIE, H., KASHANINEJAD, M., MORTEZA, K. M., ZIAIIFAR, A. M. and AKBARIAN, A. 2015. Effects of Various Essential Oils on Chemical and Sensory Characteristics and Activity of Probiotic Bacteria in Drinking Yoghurt. Agricultural Communications, 3(1): 16-21.
  14. SIMSEK, B., SAGDIC, O. and OZCELIK, S. 2007. Survival of Escherichia coli O 157:H7 during the storage of Ayran produced with different spices. Journal of Food Engineering, 78(2): 676-680. DOI: 10.1016/j.jfoodeng.2005.11.005 Go to original source...
  15. SÚTN. 2010. Mikrobiológia potravín a krmív. Horizontálna metóda na stanovenie počtu kvasiniek a plesní. Časť 1: Metóda počítania kolónií vo výrobkoch s aktivitou vody väčšou ako 0,95. STN ISO 21527-1. Bratislava: Slovenský ústav technickej normalizácie.
  16. SÚTN. 2002. Mikrobiológia potravín a krmív. Horizontálna metóda na stanovenie počtu mezofilných kyslomliečných baktérií. Metóda počítania kolónií kultivovaných pri 30 °C. STN ISO 15214. Bratislava: Slovenský ústav technickej normalizácie.
  17. SÚTN. 2009. Mikrobiológia potravín a krmív. Horizontálna metóda na stanovenie počtu koliformných baktérií. Metóda počítania kolónií. STN ISO 4832: 2009 (56 0085). Bratislava: Slovenský ústav technickej normalizácie.
  18. TAJKARIMI, M. M., IBRAHIM, S. A. and CLIVER, D. O. 2010. Antimicrobial herb and spice compounds in food. Food Control, 21(9): 1199-1218. DOI: 10.1016/j.foodcont.2010.02.003 Go to original source...

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