with the collaboration of Iranian Food Science and Technology Association (IFSTA)

Document Type : Research Article

Authors

1 Department of Food Science and Technology, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran

2 Department of Food Science and Industry, Research and Education Center Khorasan Razavi Agriculture and Natural Resources, Research, Education and Promotion Organization Agriculture, Mashhad, Iran

Abstract

Introduction
Doogh is a fermented dairy product that is produced by blending yogurt with water and some salt. This fermented beverage is widely consumed as a refreshing drink in Iran and other Middle East countries. Doogh is a source of calcium needed by the body on a daily basis and contains B vitamins that are effective in the health and strength of teeth and bones. In addition, doogh contains a low percentage of fat, which makes it a diet drink. Whey Protein Concentrate (WPC) is a product contains 25 to 89% protein and different amounts of lactose, fat and minerals. Due to the functional properties of whey protein and its nutritional value; whey protein is widely used in dairy products. The development of cross-linking bonds between protein chains by enzymes is very important today. Enzyme cross-linking of proteins can affect some of their functional properties such as solubility, water absorption, rheological and emulsifying properties. One of the most widely used enzymes in the food industry is the transglutaminase enzyme. In this study the effects of WPC in three levels (0%,1% and 2%) and the transglutaminase enzyme in two levels (0 and 1 unit per gram of milk protein) in two method of dough preparation (adding water to yogurt and fermented milk diluted with water) on rheological characteristics, and microstructure of doogh were studied.
 
Material and Methods
Raw milk was provided by Pegah Khorasan Company, WPC from Multi Company) Mashhad (and Trans glutaminease enzyme from BDF Company of Spain. WPC was first added to milk at 45 ̊ C at three levels of zero, 1 and 2%.The milk samples were then pasteurized at 85 ̊ C for 30 min. After lowering the temperature to 45 ̊ C, the enzymatic operation was performed at two levels of zero and one unit (per gram of protein).To complete the enzyme function, the samples were incubated for 180 minutes at 45 ̊ C. Then a temperature of 90 ̊ C was applied for 1 minute to inactivate the enzyme. The samples were then cooled to 45  ̊ C. At this stage, the samples were divided into two parts. In one part of the samples; milk was diluted with water in a ratio of 6% of the total dry matter for direct production of doogh. After adding the starter, the samples were transferred to an incubator and hold at 43-42 ̊ C, until the pH reaches about 4.1.Thefermented samples were then transferred to a refrigerator. In the second part, starter was added to milk to produce yogurt; after adding starter, the mix was transferred to an incubator and hold at 43-42 ̊ C, until the pH reaches about 4.1. Doogh was produced by diluting yogurt with waterto givethe final product with 6% of  total dry matter.
 
Results and Discussion
 In both production methods, in samples treated only with WPC, the average particle size increased with increasing WPClevel. In both methods, the production of only enzymatically treated samples  led to the formation of smaller particles with a more uniform shape and distribution. In samples of doogh produced by both production methods, WPC and transglutaminase enzyme changed the flow characteristics of doogh to non-Newtonian behavior. Samples made directly from milk had significantly higher viscosity than samples made from yogurt. In samples without enzymatic treatment, the microstructure was smooth and homogeneous with smaller particles than other samples. These particles settle very quickly. In the samples where WPC treatment was applied, the amount of large particles and non-uniformity increase with increasing WPC level. The distribution of particles in samples made directly from milk was more regular than samples made from yogurt.

Keywords

Main Subjects

©2023 The author(s). This is an open access article distributed under Creative Commons Attribution 4.0 International License (CC BY 4.0), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source.

  1. Afonso, I.M., & Maia, J.M. (1999). Rheological monitoring of structure evolution and development in stirred yoghurt. Journal of Food Engineering, 42(4), 183-190. https://doi.org/10.1016/S0260-8774(99)00118-1
  2. Beirami-Serizkani, F., Hojjati, M., & Jooyandeh, H. (2021). The effect of microbial transglutaminase enzyme and Persian gum on the characteristics of traditional kefir drink. International Dairy Journal, 112(10). https://doi.org/10.1016/j.idairyj.2020.104843
  3. Danesh, E., Jooyandeh, H., Samavati, V., & Goudarzi, M. (2017). Effect of enzymatic transglutaminase treatment on textural and sensory properties of low-fat Uf-Feta cheese incorporated with whey proteins using response surface optimization. Iranian Food Science and Technology Research Journal, 13(42), 282-294. (In Persian with English abstract). https://doi.org/10.22067/ifstrj.v1395i0.45870
  4. Danesh, E., Goudarzi, M., & Jooyandeh, H.(2018). Transglutaminase-mediated incorporation of whey protein as fat replacer into the formulation of reduced-fat Iranian white cheese: physicochemical, rheological and microstructural characterization. Journal of Food Measurement and Characterization, 12(4), 2416-2425. https://doi.org/10.1007/s11694-018-9858-5
  5. Danesh, E., Goudarzi, M., & Jooyandeh, H. (2017). Effect of whey protein addition and transglutaminase treatment on the physical and sensory properties of reduced-fat ice cream. Journal of Dairy Science, 100(7), 5206-5211. https://doi.org/10.3168/jds.2016-12537
  6. Bourne, M.C. (2002). Food Texture and viscosity. Consept and Measurment., New York, Academic press, p.p, 214.
  7. Færgemand, M., & Qvist, K.B. (1997). Transglutaminase: effect on rheological properties, microstructure and permeability of set style acid skim milk gel. Food Hydrocolloids, 11(3), 287-292. https://doi.org/10.1016/S0268-005X(97)80058-6
  8. Faergemand, M., Otte, J., & Qvist, K.B. (1997). Enzymatic cross-linking of whey proteins by a Ca 2+-independent microbial transglutaminase from Streptomyces lydicus. Food Hydrocolloids, 11(1), 19-25. https://doi.org/10.1016/ S0268-005X(97)80006-9
  9. Foroughi Nia, S., Abasi, S., & Hamidi Esfahani, Z. (2007). Effect of individual and combined addition of salep, tragacantin and guar gums on the stabilisation of Iranian doogh. Journal of Nutrition Scincce & Food Technology, 2(2), 15-25
  10. Foroughi Nia, S., Abasi, S., & Hamidi Esfahani, Z. (2009). Influence of shear stirring and homogenization on serum separation of doogh. Electronic Journal of Food Processing and Preservation, 1(3), 83-100. https://doi.org/20.1001.1.24233544.1388.1.3.5.9
  11. Gorji, E.G., Mohammadifar, M.A., & Ezzatpanah, H. (2011). Influence of gum tragacanth, Astragalus gossypinus, addition on stability of nonfat Doogh, an Iranian fermented milk drink. International Journal of Dairy Technology, 64(2), 262-268. https://doi.org/10.1111/j.1471-0307.2010.00658.x
  12. Janhøj, T., Frøst, M.B., & Ipsen, R. (2008). Sensory and rheological characterization of acidified milk drinks. Food Hydrocolloids, 22(5), 798-806. https://doi.org/10.1016/j.foodhyd.2007.03.006
  13. Jaros, D., Heidig, C., & Rohm, H. (2007). Enzymatic modification through microbial transglutaminase enhances the viscosity of stirred yogurt. Journal of Texture Studies, 38(2), 179-198. https://doi.org/10.1111/j.1745-4603.2007. 00093.x
  14. Kiani, H., Mousavi, M.E., Razavi, H., & Morris, E.R. (2010). Effect of gellan, alone and in combination with high-methoxy pectin, on the structure and stability of doogh, a yogurt-based Iranian drink. Food Hydrocolloids, 24(8), 744-754. https://doi.org/10.1016/j.foodhyd.2010.03.016
  15. Kiani, H., Mousavi, S.M.A., & Emam-Djomeh, Z. (2008). Rheological properties of Iranian yoghurt drink, Doogh. International Journal of Dairy Science, 3(2), 71-78. https://doi.org/10.3923/ijds.2008.71.78
  16. Kiani, H., Ebrahimzadeh Mousavi, S.M.A., Razavi, S.H., Yarmand, M.S., & Dini, A. (2009). Effect of source and amount of total solids content on the rheological properties and stability of non-fat doogh. Journal Of Agricultural Engineering Rresearch, 10(3),45-56.
  17. Köksoy, A., & Kılıç, M. (2003). Effects of water and salt level on rheological properties of ayran, a Turkish yoghurt drink. International Dairy Journal, 13(10), 835-839. https://doi.org/10.1016/S0958-6946(03)00103-1
  18. Koksoy, A., & Kilic, M. (2004). Use of hydrocolloids in textural stabilization of a yoghurt drink, ayran. Food Hydrocolloids, 18(4), 593-600. https://doi.org/10.1016/j.foodhyd.2003.10.002
  19. Kücükcetin, A. (2008). Effect of heat treatment and casein to whey protein ratio of skim milk on graininess and roughness of stirred yoghurt. Food Research International, 41(2), 165-171. https://doi.org/10.1016/j.foodres.2007.11.003
  20. Lorenzen, P.C., Neve, H., Mautner, A., & Schlimme, E. (2002). Effect of enzymatic cross‐linking of milk proteins on functional properties of set‐style yoghurt. International Journal of Dairy Technology, 55(3), 152-157. https://doi.org/10.1046/j.1471-0307.2002.00065.x
  21. Nilson, L.-E., Lyck, S., & Tamime, A.Y. (2006). Production of drinking products. In: Tamime, A. (ed.) Fermented Milks. UK: Society of Dairy Tehnology-Blackwell Science Ltd, p.p, 95-127.
  22. Ozen, A.E., & Kilic, M. (2009). Improvement of physical properties of nonfat fermented milk drink by using whey protein concentrate. Journal of Texture Studies, 40(3), 288-299. https://doi.org/10.1111/j.1745-4603.2009.00182.x
  23. Patocka, G., Cervenkova, R., Narine, S., & Jelen, P. (2006). Rheological behaviour of dairy products as affected by soluble whey protein isolate. International Dairy Journal, 16(5), 399-405. https://doi.org/10.1016/j.idairyj. 2005.05.010
  24. Penna, A.L.B., Sivieri, K., & Oliveira, M.N. (2001). Relation between quality and rheological properties of lactic beverages. Journal of Food Engineering, 49(1), 7-13. https://doi.org/10.1016/S0260-8774(00)00179-5
  25. Puvanenthiran, A., Williams, R.P.W., & Augustin, M.A. (2002). Structure and visco-elastic properties of set yoghurt with altered casein to whey protein ratios. International Dairy Journal, 12(4), 383-391. https://doi.org/10.1016/S0958-6946(02)00033-X
  26. Rodriguez-Nogales, J.M. (2006). Effect of preheat treatment on the transglutaminase-catalyzed cross-linking of goat milk proteins. Process Biochemistry, 41(2), 430-437. https://doi.org/10.1016/j.procbio.2005.07.009
  27. Sandoval-Castilla, O., Lobato-Calleros, C., Aguirre-Mandujano, E., & Vernon-Carter, E.J. (2004). Microstructure and texture of yogurt as influenced by fat replacers. International Dairy Journal, 14(2), 151-159. https://doi.org/10.1016/S0958-6946(03)00166-3
  28. Şanli, T., Sezgin, E., Deveci, O., Şenel, E., & Benli, M. (2011). Effect of using transglutaminase on physical, chemical and sensory properties of set-type yoghurt. Food Hydrocolloids, 25(6), 1477-1481. https://doi.org/10.1016/j.foodhyd.2010.09.028
  29. Schorsch, C., Carrie, H., & Norton, I.T. (2000). Cross-linking casein micelles by a microbial transglutaminase: influence of cross-links in acid-induced gelation. International Dairy Journal, 10(8), 529-539. https://doi.org/10.1016/S0958-6946(00)00069-8
  30. Shahidi, F., Ehtiati, A., Mohebi, M., & Yavarmanesh, M. (2013). The effect of WPC and starters producing exopolysaccharide on the physical properties of doogh. Iranian Food Science and Technology, 9(4), 295-303. (In Persian with English abstract). https://doi.org/10.22067/ifstrj.v9i4.30072
  31. Sharma, R., Lorenzen, P.C., & Qvist, K.B. (2001). Influence of transglutaminase treatment of skim milk on the formation of ε-(γ-glutamyl) lysine and the susceptibility of individual proteins towards crosslinking. International Dairy Journal, 11(10), 785-793. https://doi.org/10.1016/S0958-6946(01)00096-6
  32. Shirkhani, M., Madadlou, A., & Khosrowshahi, A. (2015). Enzymatic modification to stabilize the fermented milk drink, doogh. Journal of Texture Studies, 46(1), 22-33. https://doi.org/10.1111/jtxs.12107
  33. Ye, A., & Taylor, S. (2009). Characterization of cold-set gels produced from heated emulsions stabilized by whey protein. International Dairy Journal, 19(12), 721-727. https://doi.org/10.1016/j.idairyj.2009.06.003

 

CAPTCHA Image