Microstructural Characterization of High-Protein Dairy Powders
Abstract
:1. Introduction
2. Materials and Methods
2.1. Experimental Design
2.2. Milk Protein Powder Samples
2.3. Gross Compositional Analysis
2.4. Handling and Reconstitution Properties
2.5. Microstructure Using SEM
2.6. Statistical Analysis
3. Results and Discussion
3.1. Gross Composition, Handling, and Reconstitution Properties
3.2. Microstructure of Powder
3.2.1. Effect of Sputtering and Non-Sputtering Samples on the Micrograph Clarity
3.2.2. SMP and WMP (Fresh and Stored)
3.2.3. Casein-Rich Milk Protein Powders
3.2.4. Whey Protein-Rich Powders
4. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
- Global “Dairy Protein Market” Trend 2023, Prominent Players in Various Ragions, Forecast 2028—MarketWatch. 2023. Available online: www.marketwatch.com (accessed on 28 June 2023).
- Singh, R.; Rathod, G.; Meletharayil, G.H.; Kapoor, R.; Sankarlal, V.M.; Amamcharla, J.K. Invited review: Shelf-stable dairy protein beverages—Scientific and technological aspects. J. Dairy Sci. 2022, 105, 9327–9346. [Google Scholar] [CrossRef] [PubMed]
- Kinsella, J.E. Milk proteins: Physicochemical and functional properties. CRC Crit. Rev. Food Sci. Nutr. 1984, 21, 197–262. [Google Scholar] [CrossRef] [PubMed]
- Henning, D.R.; Baer, R.J.; Hassan, A.N.; Dave, R. Major Advances in Concentrated and Dry Milk Products, Cheese, and Milk Fat-Based Spreads. J. Dairy Sci. 2006, 89, 1179–1188. [Google Scholar] [CrossRef] [Green Version]
- Hammam, A.R.; Martínez-Monteagudo, S.I.; Metzger, L.E. Progress in micellar casein concentrate: Production and applications. Compr. Rev. Food Sci. Food Saf. 2021, 20, 4426–4449. [Google Scholar] [CrossRef]
- Salunke, P.; Marella, C.; Metzger, L.E. Microfiltration and Ultrafiltration process to produce Micellar Casein and Milk Protein Concentrates with 80% Crude Protein Content: Partitioning of various protein fractions and constituents. Dairy 2021, 2, 367–384. [Google Scholar] [CrossRef]
- Carter, B.G.; Cheng, N.; Kapoor, R.; Meletharayil, G.H.; Drake, M.A. Invited review: Microfiltration-derived casein and whey proteins from milk. J. Dairy Sci. 2020, 104, 2465–2479. [Google Scholar] [CrossRef] [PubMed]
- Kim, E.H.J.; Chen, X.D.; Pearce, D. Surface characterization of four industrial spray-dried dairy powders in relation to chemical composition, structure and wetting property. Colloids Surf. B Biointerfaces 2002, 26, 197–212. [Google Scholar] [CrossRef]
- Ji, J.; Fitzpatrick, J.; Cronin, K.; Maguire, P.; Zhang, H.; Miao, S. Rehydration behaviours of high protein dairy powders: The influence of agglomeration on wettability, dispersibility and solubility. Food Hydrocoll. 2016, 58, 194–203. [Google Scholar] [CrossRef] [Green Version]
- Hazlett, R.; Schmidmeier, C.; O’Mahony, J.A. Approaches for improving the flowability of high-protein dairy powders post spray drying—A review. Powder Technol. 2021, 388, 26–40. [Google Scholar] [CrossRef]
- McSweeney, D.J.; O’Mahony, J.A.; McCarthy, N.A. Strategies to enhance the rehydration performance of micellar casein dominant dairy powders. Int. Dairy J. 2021, 122, 105116. [Google Scholar] [CrossRef]
- Murayama, D.; Zhu, Y.; Ikeda, S. Correlations between the solubility and surface characteristics of milk protein concentrate powder particles. J. Dairy Sci. 2021, 104, 3916–3926. [Google Scholar] [CrossRef] [PubMed]
- Paul, A.; Martin, F.; Simard, B.; Scher, J.; Gaiani, C.; le Floch-Fouere, C.; Jeantet, R.; Burgain, J. Deciphering the segregation of proteins in high-protein dairy powders after spray-drying. J. Dairy Sci. 2022, 106, 843–851. [Google Scholar] [CrossRef] [PubMed]
- Huppertz, T.; Gazi, I.; Luyten, H.; Nieuwenhuijse, H.; Alting, A.; Schokker, E. Hydration of casein micelles and caseinates: Implications for casein micelle structure. Int. Dairy J. 2017, 74, 1–11. [Google Scholar] [CrossRef]
- Nasser, S.; Jeantet, R.; De-Sa-Peixoto, P.; Ronse, G.; Nuns, N.; Pourpoint, F.; Burgain, J.; Gaiani, C.; Hedoux, A.; Delaplace, G. Microstructure evolution of micellar casein powder upon ageing: Consequences on rehydration dynamics. J. Food Eng. 2017, 206, 57–66. [Google Scholar] [CrossRef]
- Wu, S.; Cronin, K.; Fitzpatrick, J.; Miao, S. Updating insights into the rehydration of dairy-based powder and the achievement of functionality. Crit. Rev. Food Sci. Nutr. 2022, 62, 6664–6681. [Google Scholar] [CrossRef] [PubMed]
- Dec, B.; Kiełczewska, K.; Smoczy’nski, M.; Baranowska, M.; Kowalik, J. Properties and Fractal Analysis of High-Protein Milk Powders. Appl. Sci. 2023, 13, 3573. [Google Scholar] [CrossRef]
- Kalab, M. Electron Microscopy of milk products: A review of technique. In Scanning Electron Microscopy; Part III; SCM Inc., AMT O’Hare: Chicago, IL, USA, 1981; pp. 453–472. [Google Scholar]
- Kalab, M. Microstructure of dairy foods: 1. Milk products based on protein. J. Dairy Sci. 1979, 62, 1352–1364. [Google Scholar] [CrossRef]
- Gejl-Hansen, F.; Flink, J.M. Application of microscopic techniques to the description of structure of dehydrated food systems. J. Food Sci. 1976, 41, 483–489. [Google Scholar] [CrossRef]
- Sharma, A.; Jana, A.H.; Chavan, R.S. Functionality of milk powders and milk-based powders for end use applications—A review. Compr. Rev. Food Sci. Food Saf. 2012, 11, 518–528. [Google Scholar] [CrossRef]
- Kim, E.H.J.; Chen, X.D.; Pearce, D. On the mechanisms of surface formation and the surface compositions of industrial milk powders. Dry. Technol. 2003, 21, 265–278. [Google Scholar] [CrossRef]
- Kalab, M. Scanning Electron Microscopy of dairy products: An overview. In Scanning Electron Microscopy; Part III; SCM Inc., AMT O’Hare: Chicago, IL, USA, 1979; pp. 261–272. [Google Scholar]
- Lewis, D.F. Overview of Microscopical approaches. In Structure of Dairy Products; Tamime, A., Ed.; Blackwell Publishing: Oxford, UK, 2007; pp. 1–16. [Google Scholar]
- Schmidt, D.G. Electron Microscopy of Milk and Milk Products: Problems and Possibilities. Food Struct. 1982, 1, 6. [Google Scholar]
- Lee, C.-H.; Rha, C.K. Application of scanning electron microscopy for the development of materials for food. In Scanning Electron Microscopy; Part III; SCM Inc., AMT O’Hare: Chicago, IL, USA, 1979; pp. 465–471. [Google Scholar]
- Shah, K.; Salunke, P.; Metzger, L.E. Effect of storage of skim milk powder, nonfat dry milk, and milk protein concentrate on functional properties. Dairy 2022, 3, 565–576. [Google Scholar] [CrossRef]
- Shah, K.; Salunke, P.; Metzger, L.E. High Protein Powders Fortification of Nonfat Yoghurt: Impact of Protein Source, Protein to Total Solids Ratio, Storage, and Seasonality on the Functionality of Nonfat Yoghurt Made Using Glucono-δ-Lactone (GDL). J. Food Process. Technol. 2022, 13, 1000946. [Google Scholar]
- Hooi, R.; Barbano, D.M.; Bradley, R.L.; Budde, D.; Bulthaus, M.; Chettiar, M.; Lynch, J.; Reddy, R. Chapter 15 Chemical and Physical Methods. In Standard Methods for the Examination of Dairy Products, 17th ed.; Wehr, H.M., Frank, J.F., Eds.; American Public Health Association: Washington, DC, USA, 2004; pp. 480–510. [Google Scholar]
- Niro A/S. Analytical Methods. 2008. Available online: www.niro.com (accessed on 8 January 2018).
- Silva, J.V.C.; O’Mahony, J.A. Flowability and wetting behaviour of milk protein ingredients as influenced by powder composition. Part. Size Microstruct. 2017, 70, 277–286. [Google Scholar] [CrossRef]
- van Kreveld, A. Studies on the wetting of milk powder. Neth. Milk Dairy J. 1974, 28, 23–45. [Google Scholar]
- Singh, H. Interactions of milk proteins during the manufacture of milk powders. Le Lait 2007, 87, 413–423. [Google Scholar] [CrossRef]
- Buma, T.J.; Henstra, S. Particle structure of spray-dried caseinate and spray-dried lactose as observed by scanning electron microscope. Neth. Milk Dairy J. 1971, 25, 278. [Google Scholar]
- Muller, H.R. Elekttonenmikroskopische Untersuchungen an Milch und Milchprodukten. 1. Strukturaufldii.rung in Milchpulvern. Milchwissenschaft 1964, 19, 345. [Google Scholar]
- Kalab, M.; Emmons, D.B. Milk gel structure. III. Microstructure of skim milk powder and gels as related to the drying procedure. Milchwissenschaft 1974, 29, 585. [Google Scholar]
- Vega, C.; Roos, Y.H. Spray-Dried Dairy and Dairy-Like Emulsions—Compositional Considerations. J. Dairy Sci. 2006, 89, 383–401. [Google Scholar] [CrossRef] [Green Version]
- Kalab, M. Food structure and milk products. In Encyclopedia of Food Science and Technology; Hui, Y.H., Ed.; John Eiley & Sons, Inc.: Hoboken, NJ, USA, 1992; Volume 2, pp. 1170–1196. [Google Scholar]
- Roos, Y.H. Importance of glass transition and water activity to spray drying and stability of dairy powders. Lait 2002, 82, 475–484. [Google Scholar] [CrossRef] [Green Version]
- Mistry, V.V.; Hassan, H.N. Delactosed, high milk protein powder. 2. Physical and Functional properties. J. Dairy Sci. 1991, 74, 3716–3723. [Google Scholar] [CrossRef]
- Mistry, V.V. Manufacture and application of high milk protein powder. Lait 2002, 82, 515–522. [Google Scholar] [CrossRef]
- Mistry, V.V.; Hassan, H.N.; Robinson, D.J. Effect of lactose and protein on the microstructure of dried milk. Food Struct. 1992, 11, 73–82. [Google Scholar]
- Hardy, J.; Scher, J.; Banon, S. Water activity and hydration of dairy powders. Lait 2002, 82, 441–452. [Google Scholar] [CrossRef] [Green Version]
- Verdurmen, R.E.M.; Straatsma, H.; Verschuren, V.; van Haren, J.J.; Smit, E.; Bargeman, G.; de Jong, P. Modeling spray drying processes for dairy products. Lait 2002, 82, 453–463. [Google Scholar] [CrossRef]
- Pisecky, I.J. Handbook of Milk Powder Manufacture; Westergaard, V., Refstrup, E., Eds.; GEA Process Engineering A/S (GEA Niro): Copenhagen, Denmark, 2010. [Google Scholar]
- Kalab, M.; Caric, M.; Zaher, M.; Harwalker, V.R. Composition and some properties of spray dried retantates obtained by the ultrafiltration of milk. Food Microstruct. 1989, 8, 225–233. [Google Scholar]
- Tamime, A.Y.; Robinson, R.K.; Michel, M. Microstructure of concentrated and dried milk products. In Structure of Dairy Products; Tamime, A., Ed.; Blackwell Publishing: Oxford, UK, 2007; pp. 104–133. [Google Scholar]
- Salunke, P.; Metzger, L.E. Impact of transglutaminase treatment given to the skim milk before or after microfiltration on the functionality of micellar casein concentrate used in process cheese product and comparison with rennet casein. Int. Dairy J. 2022, 128, 105317. [Google Scholar] [CrossRef]
- Salunke, P.; Marella, C.; Amamcharla, J.K.; Muthukumarappan, K.; Metzger, L.E. Use of Micellar Casein Concentrate and Milk Protein Concentrate Treated with Transglutaminase in Imitation cheese products—Melt and Stretch properties. J. Dairy Sci. 2022, 105, 7904–7916. [Google Scholar] [CrossRef]
- Salunke, P.; Marella, C.; Amamcharla, J.K.; Muthukumarappan, K.; Metzger, L.E. Use of Micellar Casein Concentrate and Milk Protein Concentrate Treated with Transglutaminase in Imitation cheese products—Unmelted texture. J. Dairy Sci. 2022, 105, 7891–7903. [Google Scholar] [CrossRef]
Characteristics | Moisture, % | Fat, % | Protein, % | Lactose, % | Ash, % |
---|---|---|---|---|---|
Fresh WMP | 3.75 ± 0.08 | 26.02 ± 0.23 | 24.82 ± 0.22 | 37.91 ± 0.33 | 6.83 ± 0.12 |
Stored WMP | 4.07 ± 0.11 | 25.98 ± 0.25 | 25.02 ± 0.19 | 38.01 ± 0.16 | 6.98 ± 0.10 |
SMP | 4.31 ± 0.18 | 0.47 ± 0.09 | 34.91± 0.32 | 52.98 ± 0.41 | 7.92 ± 0.13 |
RCN | 10.21 ± 0.20 | 0.42 ± 0.15 | 80.3 ± 0.22 | 0.09 ± 0.02 | 8.09 ± 0.13 |
WPI | 3.31 ± 0.12 | 1.57 ± 0.32 | 90.69 ± 0.33 | 3.18 ± 0.19 | 1.70 ± 0.16 |
NWC | 3.55 ± 0.31 | 0.62 ± 0.36 | 91.43 ± 0.29 | 0.14 ± 0.22 | 3.76 ± 0.12 |
MPC | 3.19 ± 0.07 | 2.26 ± 0.21 | 79.76 ± 0.35 | 7.81 ± 0.23 | 7.71 ± 0.18 |
MCC | 3.29 ± 0.09 | 2.02 ± 0.19 | 79.67 ± 0.30 | 7.31 ± 0.33 | 7.67 ± 0.11 |
Powders | Bulk Density, g/mL | HR | CI, % | Flowability | Wettability, s | ||
---|---|---|---|---|---|---|---|
0x | 10x | 100x | |||||
WMP | 0.600 a ± 0.002 | 0.625 a ± 0.004 | 0.675 a ± 0.007 | 1.13 d ± 0.02 | 11.18 e ± 1.25 | Good | 18 b ± 3 |
SMP | 0.521 b ± 0.001 | 0.569 b ± 0.001 | 0.623 b ± 0.004 | 1.20 c ± 0.01 | 16.38 d ± 0.36 | Good | 10 a ± 2 |
RCN | 0.433 c ± 0.004 | 0.457 c ± 0.002 | 0.461 c ± 0.001 | 1.06 e ± 0.01 | 6.08 f ± 0.62 | Excellent | >300 c |
WPI | 0.151 f ± 0.003 | 0.158 f ± 0.002 | 0.201 e ± 0.004 | 1.33 b ± 0.00 | 24.69 c ± 0.08 | Passable | >300 c |
NWC | 0.105 g ± 0.003 | 0.115 g ± 0.005 | 0.143 f ± 0.003 | 1.36 a ± 0.01 | 26.58 ab ± 0.53 | Poor | >300 c |
MPC | 0.193 d ± 0.004 | 0.212 d ± 0.004 | 0.257 d ± 0.004 | 1.34 b ± 0.00 | 25.10 bc ± 0.14 | Passable | >300 c |
MCC | 0.185 e ± 0.001 | 0.202 e ± 0.001 | 0.253 d ± 0.003 | 1.37 a ± 0.01 | 26.88 a ± 0.26 | Poor | >300 c |
Product | Without Sputter Coating | With Sputter Coating |
---|---|---|
SMP | It was difficult to see the surface as the charge on the particle surface caused wrinkles that appeared as white lines. Some fused particles and some with vacuoles could be seen, and particles were hollow inside. The interesting thing was that there were particles inside the larger particles. Even though it was a commercial powder, some high-temperature drying effects could be seen as collapsed particles. The powder was agglomerated. The charging effect was apparent. | The particle surface could be viewed more easily. Wrinkles were seen on particles. The surface was spherical, with varying sizes of particles. Particles were fused, round-to-collapsed, and smooth-to-wrinkled surfaces were visible. There were particles inside the larger particles, but some had vacuoles and were hollow. The charging effect was nullified by sputter coating. |
WMP | Due to the charging effect, SEM was not performed on WMP without coating. | Two powder samples were observed. One was fresh, and the other was stored at 23 °C for 12 months. The fresh sample had a fused spherical particles, and the stored sample had very large particles with many fused to form lumps. The small particles were attached to larger particles. Wrinkles were evident on the surface but appeared to be covered by some layer, possibly fat. Even after coating, the stored sample showed a charging effect. Lump formation was the difference between the fresh and stored sample. |
MPC | The MPC powder had particle shapes ranging from spherical to truncated tetrahedron to polyhedron. It had a mixture of these particles. Faces collapsed, but particles were intact. Particle surfaces were wrinkled to smooth. The charging effect was evident. | The particle surface was visible, ranging from spherical to truncated tetra-/polyhedron shapes. The unique observation was that the spherical particle had a golf-ball-like structure. At least one small particle was attached to a larger particle at a particular point. The particle surface was visible. |
MCC | The MCC powder had a large number of small particles with few spherical particles in between. The small particles resembled broken pieces of a clay pot in some photographs. Some had vacuoles, and some had broken surfaces. The charging effect was evident and caused artifacts, causing collapsed particles to appear as broken particles. | Sputtering increased the contrast and clarity of the sample. There were large numbers of small particles with unique truncated pyramids, tetrahedrons, and polyhedron shapes. A unique observation was that spherical particles had a golf-ball-like structure. Clarity and contrast were better with sputtering. MCC differed from MPC in the number of small particles, having either a truncated pyramid, tetrahedron, or polyhedron shape. |
WPI | The WPI sample had a large number of golf-ball-like structures, in which a small amount of truncated-pyramid-, tetrahedron-, and polyhedron-shaped particles were dispersed. The depth in the spherical collapse curves was more significant than in the MPC/MCC powder samples. The ratio of large particles to small particles of a unique shape was more than in MCC or MPC. It had more depth in the collapsed points on the surface of spherical particles. | Sputtering increased the contrast and clarity of the sample. |
NWC | NWC sample had a mixture of smooth surface and golf-ball-like surface particles. There was an absence of a truncated-pyramid-, tetrahedron-, and polyhedron-shaped particles. There were none or very few truncated-pyramids-, tetrahedron-, or polyhedron-shaped particles. | Sputtering increased the contrast and clarity of the sample. |
RCN | The RCN sample had a mesh size of 30. The particles were too big and had highly irregular shapes. It seems that RCN was not spray-dried. The surface was not smooth (highly wrinkled) and had holes. The difference in drying technology is evident. | Since the size of rennet casein particles was large, there was no need sputter coat of the sample. However, sputter coating increases the image clarity. |
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Salunke, P.; Syamala, A.; Metzger, L.E. Microstructural Characterization of High-Protein Dairy Powders. Dairy 2023, 4, 462-481. https://doi.org/10.3390/dairy4030031
Salunke P, Syamala A, Metzger LE. Microstructural Characterization of High-Protein Dairy Powders. Dairy. 2023; 4(3):462-481. https://doi.org/10.3390/dairy4030031
Chicago/Turabian StyleSalunke, Prafulla, Athira Syamala, and Lloyd E. Metzger. 2023. "Microstructural Characterization of High-Protein Dairy Powders" Dairy 4, no. 3: 462-481. https://doi.org/10.3390/dairy4030031