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 Animal Science and Food Technology, Ramin Agriculture and Natural Resources University of Khuzestan, Mollasani, Iran.

2 Department of Food Science & Engineering, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran.

Abstract

Introduction: Scientific evidence has demonstrated that consumption of high-fat foods has direct connection with increasing incidences of various diseases such as obesity, diabetes, hardening of the artery walls and blood pressure. Thus, demand for low-fat foods has increasingly been promoted by health-conscious consumers. However, development of low-fat foods is challenging as fat makes a major contribution to sensory attributes of many foods. Low-fat cheeses are usually characterized as having a flat taste, more translucency and a rubbery and gummy texture. A common strategy for improving the properties of low-fat cheeses is to increase its moisture content sufficiently to provide moisture to protein ratio which is greater than or equal to its full-fat counterpart. The addition of denatured whey proteins, which are known for their high water-holding capacity, to cheese milk is one method used to achieve this objective. Likewise, transglutaminase treatment of cheeses milk has been shown to increase the moisture content of the resultant cheese. Enzyme transglutaminase (MTGase; protein-glutamine gamma glutamyl transferase, EC 2.3.2.13) catalyzes acyl transfer reactions between protein intra- or inter- chain glutamine (acyl donor) and lysine (acyl acceptor) peptide residues. UF-Feta cheese has the highest per capita consumption amongst cheese varieties in Iran. However, UF-Feta cheese is also perceived as being high in fat, discouraging some consumers from including it in their diets. The objective of this study was enzymatic incorporation of whey proteins into the formulation of UF-Feta cheese by TGase in order to obtain a low-fat product with desirable textural and sensory properties.

Materials and methods: The experiments were designed according to a 5-level-3-factor central composite design using response surface methodology (RSM). The independent variable were formulation ingredients including TGase enzyme (0-2 units/g protein), whey protein concentrate (WPC) (0-16 % w/w) and fat (0-10 % w/w) and the responses of interest were the physicochemical (moisture content and lightness (L*)), textural (hardness, adhesiveness, cohesiveness and springiness) and sensory properties (flavor and odor, color and appearance, texture and total acceptability) of UF-Feta cheese.

Results and discussion: The results indicated that fat reduction caused significant increment in the moisture content of UF-Feta cheese. The whey protein addition showed the same effect on moisture content as fat reduction whereas transglutaminase treatment decreased the moisture of UF-Feta cheese. As expected, fat reduction was accompanied by an increase in hardness and elasticity of UF-Feta cheese. Fat and moisture act as fillers in the casein matrix of cheese texture. When the fat content is decreased, the moisture does not replace the fat on an equal basis, so the total filler volume is decreased, resulting in lower moisture to protein ratio. This in turn increases possibilities of cross-linking between protein chains, resulting in a more compact cheese matrix with harder and chewier texture. Similarly, the increasing effect of TGase treatment on hardness and elasticity may be attributed to formation of a more compact protein matrix because of cross-linking action of enzyme on milk proteins. The whey proteins, however, decreased the hardness and elasticity of UF-Feta cheese. It seems that the added whey proteins increased the moisture content of cheese as sufficiently as to offset the decrease in the total filler volume caused by fat reduction, preventing the protein matrix to be more compact and elastic. Promoted protein-protein interactions of the cheese matrix resulting from fat reduction or TGase treatment might also account for our observation on decreased adhesiveness and increased cohesiveness. As the protein matrix becomes more compact, the cheese loses its adhesiveness. Conversely, as the number or strength of protein interactions increases, the structural integrity of cheese matrix called cohesiveness increases. Apart from fat, water can also create more open conformation for protein molecules, resulting in increased adhesiveness and decreased cohesiveness. This may justify our observation on higher adhesiveness and lower cohesiveness of whey protein-fortified low-fat cheeses with high moisture content. Not surprisingly, all the sensory attributes of UF-Feta cheese were adversely influenced by fat reduction. On the other hand, whey proteins improved the flavor and texture of low-fat UF-Feta cheeses. They, however, showed no effect on appearance score of cheese samples in spite of the fact that they somewhat compensated for lost lightness (L*) of low-fat cheeses. Similarly, TGase treatment did not affect the appearance acceptability of UF-Feta cheeses despite having significant effect on their L* value. The sensory panel did not appreciate the flavor of TGase-treated samples; however, they scored the samples treated with enzyme concentration lower than 1 U/g protein as having desirable texture. RSM suggested that the optimum formulation of 5.95% (w/w) fat, 0.56 unit TGase per gram protein and 8.79% (w/w) WPC could produce a low-fat cheese sample with desired textural (hardness 0.342 kg; elasticity 8.58 mm; adhesiveness -0.070 kg.s; cohesiveness 0.474) and sensory (overall sensory score 88.73 out of 100) attributes.

Keywords

Alizadeh, M., Hamedi, M. & Khosroshahi, A., 2006, Modeling of proteolysis and lipolysis in Iranian white brine cheese, Food Chemistry, 97(2), 294-301.
AOAC, 2000, Official Methods of Analysis. 17th ed, Association of Official Analytical Chemists, Gaithersburg, Maryland, USA.
Broadbent, J., McMahon, D., Oberg, C. & Welke, D., 2001, Use of exopolysaccharide-producingcultures to improve the functionality of low fat cheese, International Dairy Journal, 11, 433–439.
Cooke, D. R., Khosrowshahi, A. & McSweeney, P. L., 2013, Effect of gum tragacanth on the rheological and functional properties of full-fat and half-fat Cheddar cheese, Dairy Science & Technology, 93(1), 45-62
Dimitreli, G. & Thomareis, A. S., 2007, Texture evaluation of block-type processed cheese as a function of chemical composition and in relation to its apparent viscosity, Journal of Food Engineering, 79, 1364-1373.
Di Pierro, P., Mariniello, L., Sorrentino, A., Giosafatto, L. C., Chianese, L. & Porta, R., 2010, Transglutaminase-induced chemical and rheological properties of cheese, Food Biotechnology, 24,107-120.
El-Sheikh, M. M., Farrag, A. F., Shahein, N. M. & El-Shibiny, S., 2001, Low fat Domiati cheese with particulated whey protein concentrate (PWPC), Egyptian Journal of Dairy Science, 29(2), 331-342.
Egan, H., Kirk, R. S. & Sawyer, R., 1981, Pearson’s Chemical Analysis of Foods. pp 497-499. eighth edition, Longman Scientific and Technical Bath Press, Avon, UK.
Fernandes-DE Sa, E. M., & Bordignon-Luiz, M. T., 2010, The effect of transglutaminase on the properties of milk gels and processed cheese, International journal of dairy technology, 63(2), 243-251.
Fox, P. F., Guinee, T. P., Cogan, M. T. & McSweeney, P. L. H., 2000, Fundamentals of cheese science, Aspen publication.
Gaspar, A. L. C. & de Goes-Favoni, S. P., 2015, Action of microbial transglutaminase (MTGase) in the modification of food proteins: A review, Food chemistry, 171, 315-322.
Goudarzi, M., Madadlou, A., Mousavi, M. E. & Emam-Djomeh, Z., 2015, Formulation of apple juice beverages containing whey protein isolate or whey protein hydrolysate based on sensory and physicochemical analysis, International Journal of Dairy Technology, 68 (1), 70-78.
Gunasekaran, S. & Mehmet, A. k. M., 2003, Cheese rheology and texture, CRC Press.
IDF, 1987, Sensory evaluation of dairy products. Standard 99A, International Dairy Federation, Brussels.
Imeson, A. P., 2000, Carrageenan. Hand book of Hydrocolloids. Edited by Phillips,G.O and Williams, P. A.Woodhead Publishing Limited and CRC Press LLC.
Imm, J. Y., Lian, P. & Lee, C. M., 2000, Gelation and water binding properties of transglutaminase-treated skim milk powder, Journal of Food Science, 65,200-205.
Jooyandeh, H., 2009, Effect of fermented whey protein concentrate on texture of Iranian white cheese, Journal of Texture Studies, 40, 497-510.
Karami, M., Ehsani, M. R., Mousavi, M. E., Rezaei, K. & Safari, M., 2008, Microstructural changes in fat during the ripening of Iranian ultrafiltered Feta cheese, Journal of dairy science, 91(11), 4147-4154.
Katsiari, M. C., Voutsinas, L. P., Kondyli, E. & Alichanidis, E., 2002, Flavour enhancement of low-fat Feta-type cheese using a commercial adjunct culture, Food chemistry, 79(2), 193-198.‏
Koca, N. & Metin, N., 2004, Textural, melting and sensory properties of low-fat fresh Kashar cheese produced by using fat replacers, International Dairy Journal, 14, 365-373.
Lee, S. K., Huss, M., Klostermeyer, H. & Anema, S. G., 2013, The effect of pre-denatured whey proteins on the textural and micro-structural properties of model processed cheese spreads, International Dairy Journal, 32(2), 79-88.
Lobato‐Calleros, C., Robles-Martinez, J. C., Caballero-Perez, J. F., Vernon-Carter, E. J. & Aguirre‐Mandujano, E., 2001, Fat Replacers in Low‐Fat Mexican Manchego Cheese, Journal of Texture Studies, 32(1), 1-14.
Lo, C. G. & Bastian, E. D., 1998, Incorporation of native and denatured whey proteins into cheese curd for manufacture of reduced fat, Havarti-type cheese, Journal of dairy science, 81(1), 16-24.
Madadlou, A., Khosroshahi, A. & Mousavi, M. E., 2005, Rheology, microstructure, functionality of low-fat Iranian White cheese made with different concentrations of rennet. Journal Dairy Science, 88, 3052–3062.
Michaelidou, A., Katsiari, M., Kondyli, E., Voutsinas, L. & Alishanidis, E., 2003, Effect of a commercial adjunct culture on proteolysis in low-fat Feta-type cheese, International Dairy Journal, 13, 179-189.
Mistry, V., 2001, Low fat cheese technology, International Dairy Journal, 11, 413–422.
Mleko, S., Gustaw, W., Glibowski, P. & Pielecki, J., 2004, Stress relaxation study of UF-milk cheese with transglutaminase, Egyptian Journal of Dairy Science, 32, 237-244.
Özer, B. H., Robinson, R. K. & Grandison, A. S., 2003, Textural and microstructural properties of Urfa cheese (a white-brined Turkish cheese), International Journal of Dairy Technology, 56,171-176.
Ozer, B., Adnan Hayaloglu, A., Yaman, H., Gürsoy, A. & Sener, L, 2013, Simultaneous use of transglutaminase and rennet in white-brined cheese production, International Dairy Journal, 33, 129-134.
Rahimi, J., Khosrowshahi, A., Madadlou, A. & Aziznia, S., 2007, Texture of Low-Fat Iranian White Cheese as Influenced by Gum Tragacanth as a Fat Replacer, American Dairy Science Association, 90, 4058–4070.
Ritvanen, T., Lampolahti, S., Lilleberg, L., Tupasela, T., Isoniemi, M., Appelbye, U. & Uusi-Rauva, E., 2005, Sensory evaluation, chemical composition and consumer acceptance of full fat and reduced fat cheeses in the Finnish market, Food quality and preference, 16(6), 479-492.
Romeih, EA, Michaelidou, A., Biliaderis, CG. & Zerfiridis, G., 2002, Low-fat white-brined cheese made from bovine milk and two commercial fat mimetics: chemical, physical and sensory attributes, International Dairy Journal, 12(6), 525-540.
Rudan, M. A., Barbano, D. M., Yun, J. J. & Kindstedt, P. S., 1999, Effect of fat reduction on chemical composition, proteolysis, functionality, and yield of Mozzarella cheese, Journal of dairy science, 82(4), 661-672.
Saint-Eve, A., Lauverjat, C., Magnan, C., Deleris I. & Souchon, I., 2009, Reducing salt and fat content: impact of composition, texture and cognitive interaction on the perception of flavored model cheeses, Food Chemistry, 116, 167-175.
Sayadi, A., Madadlou, A. & Khosrowshahi, A., 2013, Enzymatic cross-linking of whey proteins in low fat Iranian white cheese, International Dairy Journal. 29: 88-92.
Sipahioglu, O., Alvarez, V. B. & Solano Lopez, C., 1999, Structure, physicochemical and sensory properties of Feta cheese made with Tapioca starch and lecithin as fat mimetic, International -Dairy Journal, 9, 783-789.
Ye, A. & Taylor, S., 2009, Characterization of cold-set gels produced from heated emulsions stabilized by whey protein, International Dairy Journal, 19, 721–727.
Zalazar, C. A., Zalazar, C. S., Bernal, S., Bertola, N., Bevilacqua, A. & Zaritzky, N., 2002, Effect of moisture level and fat replacer on physicochemical, rheological and sensory properties of low fat soft cheeses, International Dairy Journal, 12(1), 45-50.
Zisu, B. & Shah, N. P., 2005, Textural and functional changes in low-fat Mozzarella cheese in relation to proteolysis and microstructure as influenced by the use of fat replacers, pre-acidification and EPS starter, International Dairy Journal, 15, 957-972
CAPTCHA Image