89-5 |
Effect of sodium lactate on water mobility and glass transition temperature in intermediate moisture turkey meats |
T. C. S. YANG1, A. P. P. Yang2, I. A. Taub2, and R. Ruan3. (1) Advanced Processing and Packaging, Defense Department, U. S. Army, E-106, Natick Soldier Center, Kansas Street, Natick, MA 01760-5018, (2) Senior Scientist Office, Defense Department, U. S. Army, E-108, Natick Soldier Center, Kansas Street, Natick, MA 01760-5018, (3) Biosystems and Agricultural Engineering, University of Minnesota, 1390 Eckles Ave., St. Paul, MN 55108 Sodium lactate is known to be an effective humectant and also a specific bacterial growth suppressant in meats and other products. However, the influence of this humectant on the food matrix and specifically on the water mobility and glass transition temperature is not clearly understood. The objective was to study the relationship among moisture content (MC), water mobility (T1 & T2) and glass transition temperature (Tg) in intermediate moisture (IM) turkey of differing water activities with 1, 2, or 3 % sodium lactate or a mixture of sodium lactate and lactic acid. Turkey rolls containing 6% glycerol with 1, 2, or 3 % sodium lactate, or a mixture of 1.5 % sodium lactate and 1.5 % lactic acid were prepared. They were dried to Aw of 0.92, 0.90, 0.88 and 0.86 using a microwave-assisted freeze dryer. Moisture content was measured by AOAC method. NMR spin-lattice relaxation time (T1) and spin-spin relaxation time (T2) of the samples were measured at room temperatures (23oC). The temperature scan method, ranging from -110 to 0oC, was used to determine Tg. For turkey meats containing 1, 2, or 3 % sodium lactate, higher Aw showed higher T1, amplitude and T2. The T1, amplitude and T2 data did increase at lower level Aw levels with increasing sodium lactate suggesting that sodium lactate effect, as a humectant, is more significant at low Aw levels. For mixed sodium lactate and lactic acid samples T1, amplitude and T2 were lower than 3 % sodium lactate at the same Aw. Tg was lower than 3 % sodium lactate at the same Aw. For turkey meats containing 1, 2, or 3 % sodium lactate, Tg decreased with increasing Aw while increased with increasing sodium lactate suggesting sodium lactate as a anti-plasticizer.
Session 89, Product Development
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