Functional and thermal characteristics of Buffalo's milk protein products
Treść / Zawartość
Buffalo’s milk protein products, total milk proteinate (TMP), rennet casein, and lactic acid casein were studied. The chemical composition was determined and some properties (water and oil absorption capacity, emulsion activity, foam expansion, and buffer capacity) of these products were also determined. The results indicated some differences in the chemical composition and electrophoresis bands of protein between total milk proteinate, rennet casein and lactic acid casein. The TMP was characterised by the lowest ash and moisture contents with highest protein contents compared to the other protein products. There is no remarkable effect of drying methods on the chemical composition within each type of protein products. Total milk proteinate contains some whey proteins which are high in alanine, cystine when compared with rennet casein. Lactic acid casein had high contents of amino acid proline. On the other hand, the rennet casein had a low content of sulfur containing amino acids cysteine and methionine. Differences between total essential amino acid (TEAA) of total milk proteinate and lactic acid casein were significantly (p<0.05) higher than those of rennet casein. Freeze dried total milk proteinate exhibited excellent foaming and emulsifying potential when compared with oven-dried caseinate. For all protein types, the maximum WAC can be seen for freeze-dried milk proteinates, whereas the minimum value was for oven dried rennet casein. The minimum value of emulsion capacity and surface tension was obtained at pH 4.5 and 2.5 in all types of proteinates, whereas the maximum values were found at pH 10.5. Relative viscosity of TMP solutions was higher than those of rennet and lactic acid casein. However, relative viscosity values tended to decrease with lowering or increasing the pH values of the solutions from the neutral pH value. Calorimetric analysis showed two major enthalpy changes in the tested caseinate samples. The first change occurred at peak temperature range of 92.2°C to 100.8°C for the moisture removal, while the second change occurred between 273.9°C and 314.6°C for protein degradation. The enthalpy values ranged between 218.3 to 268.4 J/g for moisture removal. Total milk proteinate showed two major peaks for protein degradation indicating the presence of whey proteins and milk caseins.
- 1. Alsmeyer H.R., Cuningham A.E., Happich M.L., Equation predict PER from amino acid analysis. Food Technol., 1974, 28, 34–40.
- 2. AOAC, Association of Official Analytical Chemists. Official Methods of Analysis. 2007, 18th Ed., Chapter 33, pp. 7, 10–14, Benjamin Franklin Station Washington, D.C., USA.
- 3. Cohen S.A., Meys M., Tarvin T.L., A Manual of Advanced Techniques for Amino Acid Analysis. 1989, Waters Company, USA.
- 4. Czuchajowska A., Pomeranz Y., Differential scanning calorimetric, water activity and moisture contents in crumb center and near-crust zones of bread during storage. Cereal Chem., 1989, 66, 305–309.
- 5. Dean A.L, Mariette F., Lucas T., Marin M., Assessment of the state of water in reconstituted milk protein dispersions by Nuclear Magnetic Resonance(NMR) and Differential Scanning Calorimetry (DSC). Lebens. Wiss. Technol., 2001, 34, 299–305.
- 6. Dekanterewicz R.J., Elizalde E.B., Pilosof R.M.A., Bartholomi B.G., Water-oil absorption index (WOAI): A simple method for predicting the emulsifying capacity of food proteins. J. Food Sci., 1987, 52, 1381.
- 7. Fox P.F., Development in Dairy Chemistry. Chapter 4. Functional Milk Proteins. 1989, Elsevier Appl. Sci., London and New York.
- 8. Gloyna D., Schreck S., Schierbaum F., Thermoanalytical studies on starch and starch containing systems. Starch/Staerke, 1991, 43, 431–437.
- 9. Jayasena V., Chih H.J., Nasar-Abbas S.M., Functional properties of sweet lupin protein isolated and tested at various pH levels. Res. J. Agric. Biol. Sci., 2010, 6, 130–137.
- 10. Kristrnsen D., Jensen P.Y., Madsen F., Birdi K.S., Rheology and surface tension of selected processed dairy fluids: Influence of temperature. J. Dairy Sci., 1997, 80, 2282–2290.
- 11. Lampert L.M., The milk proteins. 1970, in: Modern Dairy Products. Eurasia Publishing House (P) LTD., Ram Nagar, New, p. 37.
- 12. Metwally A.I., Comparative study between functional properties of spray dried buffalos ultrafiltrated skim milk retentate and total milk proteinate. Annals Agric. Sci., Ain Shams Uni. Cairo, 1997, 42, 313–320.
- 13. Metwally A.I., Awad R.A., Buffer intensity and function properties of low and high heat milk powders. Egyptian J. Dairy Sci., 2001, 29, 19–28.
- 14. Metwally A.I., Smith D.M., Surface activity and amino acid and mineral contents of buffalo milk protein products. Proc. 8th Egypt. Conf. Dairy Sci. & Techn., 2001, pp. 211–222.
- 15. Morr C.V., Functional of heated milk proteins in dairy and related foods. J. Dairy Sci., 1985, 68, 2773–2781.
- 16. Morr C.V., Functional of milk protein and their use as food ingredients. 1982, in: Development in Dairy chemistry. 1- Protein (ed. P.F. Fox). Applied Science. London and New York, pp. 375–399.
- 17. Morr C.V., Swenson E.P., Richter L.R., Functional characteristics of whey protein concentrate. J. Food Sci., 1973, 38, 324–330.
- 18. Patel P.D., Stripp M.A., Fry C.J., Whipping test for the determination of foaming capacity of protein: A collaborative study. Int. J. Food Sci. Technol., 1988, 23, 57–63.
- 19. Pearce K.N., Kinsella J.E., Emulsifying properties of proteins: Evaluation of a turbid- metric technique. J. Agric. Food. Chem., 1978, 26, 716–723.
- 20. Raikos V., Effect of heat treatment on milk protein functionality at emulsion interfaces. A review. Food Hydrocoll., 2010, 24, 259–265.
- 21. Rao M.A., Rheology of fluid and semisolid foods. 1999, Aspen Puplication, Maryland, USA, pp. 87–88.
- 22. Rawel H.M, Rohnes S., Krall J., Influence of a sugar moiety (rhamnosylglucoside) at 3-O position on the reactivity of quercetin with whey protein. Int. J. Biol. Macromol., 2003, 32, 109–120.
- 23. Ross K.D., Rapid determination of α- lactose in whey protein by differential scanning calorimetry. J. Dairy Sci., 1978, 61, 255–259.
- 24. Salaün F., Mietton B., Gaucheron F., Buffering capacity of dairy products. Int. Dairy J., 2005, 15, 95–109.
- 25. Salaün F., Mietton B., Gaucheron F., Influence of mineral environment on the buffering capacity of casein micelles. Milchwissenschaft, 2007, 62, 20–23.
- 26. Singh H., Ye A., Interactions and functionality of milk proteins in food emulsions. 2009, in: Milk Proteins: from Expression to Food (eds. A. Thompson, M. Boland, H. Singh). Academic Press, San Diego, CA,). pp. 321–345.
- 27. Snoeren T.H.M., Damman A.J., Klok H.J., The viscosity of skim milk concentrate. Neth. Milk Dairy J., 1982, 36, 305.