Incredible Edible Hardboiled Egg By Sam Anderson and

Incredible Edible (Hard-boiled) Egg By Sam Anderson and Eugene Hart

Objective To Determine if Quiz #3 is Accurate by…. Calculating the time required to reach 160°F or 71°C in the center of the egg (safe eating temperature) Quiz #3 uses thermophysical properties of water Use thermophysical properties of an egg yolk with the given geometry from Quiz #3 Use thermophysical properties of an egg yolk with the actual geometrical measurements Boiling the eggs for the calculated times to verify

Property Comparison Egg ≈Water (Quiz #3, r=1 in. ) ρ=993 [kg/m 3] cp=4178 [J/kg·K] k=0. 628 [W/m·K] α=k/ρcp=0. 15 e-6 [W/m·k] Bi=hr/k=16. 2 C 1=1. 95 ς1=2. 9 r=0. 0254 m Egg properties 1 (r=1 in. ) ρ=1131. 74 [kg/m 3] cp=2639. 76 [J/kg·K] k=0. 3985 [W/m·K] α=k/ρcp=0. 133 e-6 [W/m·k] Bi=hr/k=25. 49 C 1=1. 97 ς1=2. 98 r=0. 0254 m Egg properties 1 (actual rad. ) ρ=1131. 74 [kg/m 3] cp=2639. 76 [J/kg·K] k=0. 3985 [W/m·K] α=k/ρcp=0. 133 e-6 [W/m·k] Bi=hr/k=23. 2 C 1=1. 97 ς1=2. 98 r=0. 0227 m

Calculations Approximate Analytical Solution Egg ≈Water (Quiz #3, r=1 in. ) Bi=16. 2 Tdone=160°F or 71°C T∞ =21. 39°C Ti = 4. 5°C t(71°C)=17 min. Egg properties 1 (r=1 in. ) Egg properties 1 (actual rad. ) Bi=25. 49 Tdone=160°F or 71°C T∞ =21. 39°C Ti = 4. 5°C t(71°C)= 9 min. 6 sec. Bi=23. 28 Tdone=160°F or 71°C T∞ =21. 39°C Ti = 4. 5°C t(71°C)= 7 min. 48 sec.

The Experiment

The Experiment Continued 84. 6°C in the Center after 17 min. of boiling

The Experiment Continued 79. 8 °C in the Center after 9 min. of boiling

The Experiment Continued 70. 9°C in the Center! After 7. 48 min. of boiling ≈71°C!

References “Continuous Pastuerization of Egg Yolk: Thermophysical Properties and Process Simulation” by Gut, Pinto, Gabas, and Telis-Romero http: //www 3. interscience. wiley. com/cgibin/fulltext/118650543/HTMLSTART � 2 http: //www. incredibleegg. org/? utm_campaign=&utm_medium=cpc&utm_source=Google&utm_conte nt=&utm_term=eggs&gclid=CJj. Mbe. P 36 ACFQyki. Qod. ZHv. D 0 A � 1