15E-18 |
Interactions of precipitated calcium carbonate (PCC) with proteins in the calcium fortification of dairy and non-dairy beverages |
S. D. COX, Specialty Minerals Inc., 9 Highland Ave., Bethlehem, PA 18017-9482 and J. L. Miller. Calcium fortification of foods and beverages is important to prevent osteoporosis and improve general bone health. This can be challenging because calcium ion interacts strongly with food components such as proteins. Most previous studies of calcium-protein interactions have utilized soluble calcium sources. Little work is reported on insoluble calcium sources such as calcium carbonate. The objective of this study was to determine how precipitated calcium carbonate (PCC) interacts with proteins used in dairy and non-dairy beverages (non-fat dry milk, whole milk, casein, whey, and soy). Solutions of each protein were compared with and without PCC added. Changes in pH, viscosity, settling stability and temperature stability due to added PCC were determined. Addition of PCC to non-fat dry milk suspensions caused very minor or insignificant changes in the properties tested. Milk pH increased only 0.2 units to 7.2, presumably due to a buffering effect from the milk itself. The PCC-containing suspension formed a soft settle over a few days, indicating the need for a stabilizer. Heating to 80 or 100°C for 5 minutes caused no change in pH or viscosity with or without PCC. Soy protein isolate showed a slightly greater interaction with PCC, especially reduced pH buffering. This work shows that PCC interacts weakly with dairy and non-dairy proteins, so calcium fortification should not be difficult. Production process conditions (such as UHT pasteurization) and other beverage components may generate other, more significant interactions, which will be studied in the future.
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Session 15E, Nutraceuticals & Functional Foods I
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