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NMR Relaxometry of Water in Set Yogurt During Fermentation  

Mok, Chul-Kyoon (Department of Food Science and Biotechnology, Kyungwon University)
Qi, Jinning (Department of Bioproducts and Biosystems Engineering, University of Minnesota)
Chen, Paul (Department of Bioproducts and Biosystems Engineering, University of Minnesota)
Ruan, Roger (Department of Bioproducts and Biosystems Engineering, University of Minnesota)
Publication Information
Food Science and Biotechnology / v.17, no.5, 2008 , pp. 895-898 More about this Journal
Abstract
The mobility of water in set yogurt during fermentation was studied using nuclear magnetic resonance (NMR) relaxometry. The spin-spin relaxation was analyzed using a 2-fraction model, resulting in 2 spin-spin relaxation time constants $T_{21}$ and $T_{22}$. Both $T_{21}$ and $T_{22}$ exhibited rapid changes between 2 and 4 hr of fermentation, coinciding with the drop in pH and the rise in lactic acid bacteria count. The spin-lattice relaxation time $T_1$ increased over the fermentation period. Both $T_1$ and $T_2$ showed an increase in the mobility of water upon gel formation during fermentation. Water redistribution within the gel matrix due to casein aggregation and structure forming may be responsible for the changes in mobility.
Keywords
yogurt; fermentation; nuclear magnetic resonance; relaxometry; water mobility; protein; casein;
Citations & Related Records

Times Cited By Web Of Science : 4  (Related Records In Web of Science)
Times Cited By SCOPUS : 2
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1 Krasaekoopt W, Bhesh B, Deeth H. Yogurt from UHT milk: A review. Aust. J. Dairy Technol. 58: 26-29 (2003)
2 Kinsella JE, Fox PF. Water sorption by proteins: Milk and whey proteins. Crit. Rev. Food Sci. 24: 91-139 (1986)   DOI   ScienceOn
3 Lucey JA. Formation and physical properties of milk gels. J. Dairy Res. 85: 281-294 (2002)   DOI   ScienceOn
4 Ruan RR, Chen PL. Molecular magnetic resonance techniques and their application in food quality analysis. pp. 165-216. In: Nondestructive Food Evaluation. Gunasekaran S (ed). Marcel Dekker, Inc., New York, NY, USA (2001)
5 Roefs SPFM, Van As H, Van Vliet T. Pulse NMR of casein dispersions. J. Food Sci. 54: 704-708 (1989)   DOI
6 Zhang Q, Matsukawa S, Katanabe T. Theoretical analysis of water $^1H\;T_2$ based chemical exchange and polysaccharide mobility during gelation. Food Hydrocolloid 18: 441-449 (2004)   DOI   ScienceOn
7 Chen PL, Long Z, Ruan R, Labuza T. Nuclear magnetic resonance studies of water mobility in bread during storage. Lebensm.-Wiss. Technol. 30: 178-183 (1997)   DOI   ScienceOn
8 Vasbinder AJ, Alting AC, Visschers RW, de Kruif CG. Texture of acid milk gels: Formation of disulfide cross-links during acidification. Int. Dairy J. 13: 29-38 (2003)   DOI   ScienceOn
9 Everett DW, McLeod RE. Interactions of polysaccharide stabilisers with casein aggregates in stirred skim-milk yogurt. Int. Dairy J. 15: 1175-1183 (2005)   DOI   ScienceOn
10 Haque A, Richardson RK, Morris ER. Effect of fermentation temperature on the rheology of set and stirred yogurt. Food Hydrocolloid 15: 593-602 (2001)   DOI   ScienceOn
11 Han J, Ruan RR, Park CH. Prediction of hydrogel pore size by pulse NMR and neural networks. Biotechnol. Tech. 9: 637-642 (1995)   DOI   ScienceOn
12 Sodini I, Remeuf F, Haddad S, Corrieu G. The relative effect of milk base, starter, and process on yogurt texture: A review. Crit. Rev. Food Sci. 44: 113-137 (2004)   DOI   ScienceOn
13 Harrigan WF. Determination of the number and detection of viable microorganisms in a sample. pp. 52-70. In: Laboratory Methods in Food Microbiology. 3rd ed. Academic Press, San Diego, CA, USA (1998)
14 Horen DS. Casein interactions: Casting light on the black boxes, the structure in dairy products. Int. Dairy J. 8: 171-177 (1998)   DOI   ScienceOn
15 Kalab M. Electron microscopy of foods. pp. 43-104. In: Physical Properties of Foods. Peleg M, Bagley EB (eds). AVI Publishing Co., Westport, CT, USA (1983)
16 Ruan RR, Han J, Chen PL, Martinez BC. Pulse NMR study of structural characteristics of temperature-sensitive hydrogel. Biotechnol. Tech. 11: 257-260 (1997)   DOI   ScienceOn
17 Parnell-Clunies EM. Influence of heat-induced protein changes in milk on the physical and ultrastructural properties of yogurt. PhD thesis, University of Guelph, ON, Canada (1986)
18 Prentice JH. Dairy Rheology - A Concise Guide. VCH Publishing, Inc., New York, NY, USA. p.125 (1992)
19 Tamine AY, Robinson RK. Yoghurt: Science and Technology. 2nd ed. CRC Press, Boca Raton, FL, USA. pp.79-82 (1999)
20 Fiszman SM, Salvador A. Effect of gelatin on the texture of yoghurt and of acid-heat-induced milk gels. Z. Lebensm. Unters. F. A. 208: 100-105 (1999)   DOI
21 Heertje I, Visser J, Smits P. Structure formation in acid milk gels. Food Microstruct. 4: 267-277 (1985)
22 Rasic JL, Kurmann JA. Yogurt - Scientific Grounds, Technology, Manufacture, and Preparations. Technical Dairy Publishing House, Copenhagen, Denmark. p. 149 (1978)
23 Mariette F, Topgaard D, Jonsson B, Soderman O. $^1H$ NMR diffusometry study of water in casein dispersions and gels. J. Agr. Food Chem. 50: 4295-4302 (2002)   DOI   ScienceOn