Biacetyl, the flavoring that makes margarine taste "just like butter," is extremely stable at room temperature, but at 200°C it undergoes a first-order breakdown with a half-life of 9.0 min. An industrial flavor-enhancing process requires that a butter-flavored food be heated briefly at 200°C. How long can the food be heated at this temperature and retain 87% of its buttery flavor? (units in min)
2006-09-18 08:56:26 · 3 answers · asked by Lauren 1 in Education & Reference ➔ Homework Help
I have to disagree with Mark's answer, he's assuming a linear breakdown, but this is a geometric breakdown.
With a half life of 9 minutes, you have 50% left at that time, so after 18 minutes you have 25% left, 27 minutes you have 12.5% left, etc.
To reverse that, after 3 minutes you would have 75% left (3 being the square root of 9), and to get 87% left, you would stop after the square root of 3 minutes, or about 1.73 minutes.
2006-09-18 09:18:19 · answer #1 · answered by Kutekymmee 6 · 0⤊ 0⤋
My answer would be 2.34 min. Assuming buttery flavor correlates to first order breakdown. Look at a number line going from 100 to 50. 87 is 26% of the way from 100 to 50. 26% of 9 min is 2.34 min.
2006-09-18 16:03:46 · answer #2 · answered by Mark S 3 · 0⤊ 0⤋
Good lord what are they teaching in school nowadays?
2006-09-18 16:03:44 · answer #3 · answered by little fairy lady 3 · 0⤊ 0⤋