, Unknown said...
Like all entries of the Liebeck case into popular media, this one builds a straw-man about what the "conventional wisdom" is about the case, and perpetuates falsehoods that have become the conventional wisdom about the case.
As Vox summarizes your video above:
–– Stella Liebeck was a 79-year-old woman in Albuquerque, New Mexico, whose grandson drove her to McDonald’s in 1992. She was in a parked car when the coffee spilled.
–– Liebeck acknowledged that the spill was her fault. What she took issue with was that the coffee was so ridiculously hot — at up to 190 degrees Fahrenheit, near boiling point — that it caused third-degree burns on her legs and genitals, nearly killing her and requiring extensive surgery to treat.
((Analysis: Given the circumstances of clothing, mobility, and time of contact, hot liquid at any temperature above 130°F would have given such severe burns.))
–– McDonald’s apparently knew that this was unsafe. In the decade before Liebeck’s spill, McDonald’s had received 700 reports of people burning themselves. McDonald’s admitted that its coffee was a hazard at such high temperatures. But it continued the practice, enforced by official McDonald’s policy, of heating up its coffee to near-boiling point. (McDonald’s claimed customers wanted the coffee this hot.)
((Analysis: 700 reports over 10 years of coffee sales -- for every person managing to injure themselves with McDonalds coffee, over 24 million people (!) managed to buy and consume the coffee without problem. • We all use products that can cause serious injury when used negligently, this does not mean that those products are unreasonably dangerous when and if used properly.
–– Liebeck didn’t want to go to court. She just wanted McDonald’s to pay her medical expenses, estimated at $20,000. McDonald’s only offered $800, leading her to file a lawsuit in 1994.
((Analysis: Liebeck sought $20,000 initially from PTS Inc, the local franchise operator -- a smalltime local businessman, not a multinational corporation. It was PTS who offered $800, PTS who was sued in a case filed on March 21, 1993, and only later was PTS replaced by McDonalds as the defendant in the case.))
–– After hearing the evidence, the jury concluded that McDonald’s handling of its coffee was so irresponsible that Liebeck should get much more than $20,000, suggesting she get nearly $2.9 million to send the company a message.
((true, and why the case became notable. Many apprised of the full facts of the case, and many more people on hearing incomplete facts condider this to be a ridiculous result. The appeals court found the punitive damages to be excessive as a matter of law.))
–– Liebeck settled for less than $600,000.
((Analysis: Unknown, the actual settlement was confidential. Had Liebec accepted the judgement of the appeals court and New Mexico Supreme Court, she would have received $140000 in compensatory and $480000 in punitive damages.))
–– And McDonald’s began changing how it heats up its coffee.
((Analysis: Mixed - McDonalds started adding the cream and sugar to customer specification before handing it out the drive-though window. The "hot liquid" warnings were already present on the cups and lids before this event. The brew and hold temperatures remain in the 180°+ range.
Google news is a wonderful thing, and it is fairly easy to do date-restricted searches that demonstrate that the press reports contemporaneous to the court case and appeals process got most of the details right, whereas the more modern "debunkings" are just parroting the anti-tort-reform talking points of the American Trial Lawyers Association, more lately known as the The American Association For Justice.
, Josh Washman said...
Who wants coffee at 190 degrees? Even 150 will scald you in 2 seconds. Do people really enjoy waiting 30 minutes to drink it and blowing on the cup before each sip, or are we just a society of burn-loving masochists? Neither.
See this for reference: https://www.ncbi.nlm.nih.gov/pubmed/18226454
McDonald's wanted to serve it at this temperature because it allowed faster serving after brewing, period. Customer safety be damned. That's why the jury proactively awarded punitive damages.
, Unknown said...
• Consumer reports will fail any coffeemaker that doesn’t have a "hold" temperature of at at least 170°F
• The specialty coffee association (http://www.scaa.org/?page=cert2) won’t certify a machine that doesn’t brew at 92-96°C (198°F) and hold coffee at >80°C (176°F). The manual for any commercial coffeemaker (such as Bunn) will recommend similar brew and hold (serve) temperatures.
• The ANSI standard for home coffeemakers states that the temperature in the dispensing vessel should be kept above 76°C
It is extremely well documented from properly done sensometric testing and chemical analysis that: as the cup temperature decreases, the volatile aromatic compounds which add positive characteristics to the flavor fall below their boiling points, and the compounds that add negative characteristics then predominate.
I would see your reference, but it is gated. I've requested a copy, and I'll report back after I've read it – I have a suspicion that I've seen that paper before, but I can't tell you where they went wrong without seeing the procedures section.
But in answer to your question: "who wants coffee at 190°", the answer is that I do. I want it fresh ground, brewed at 93°C+/-3*, held in a closed pre-warmed thermal carafe at ~80°C for no more than 30 minutes. The reason that coffeeshops which switch to 60°C serve temperatures "for safety" always revert to ~80°C is because the customers either complain vociferously or stop coming. If I find that my coffee is too hot, I can always let it cool, transfer it to a conductive ceramic mug, add more milk, or add an ice-cube. If it comes to me tepid already, there is no recourse - microwaving it only does more harm to the flavour.
, Unknown said...
Essentially they are saying that while there is no overlap between the what-can-scald and what-is-pleasurable temperature for coffee, one can assign arbitrary weightings to the importance of burns and pleasure and come up with a "figure of demerit" that is optimum: You will neither be safe from scalding or derive maximum enjoyment the coffee, but be at some happy medium. Rather like saying there is a happy medium of chain-speed or sharpness where chainsaws will still cut trees (very poorly) but the injury-risk will be greatly reduced if you hit a body part with it.
One part of the equation is that burn severity is known to increase with the temperature of the liquid causing the scald: "the standard exponential dependence of injury level on temperature". The other part of the equation is the preferred temperature for drinking coffee, which they just grab from another study (something else for me to order...): H.S. Lee, M. O’Mahony "At what temperatures do consumers like to drink coffee?: mixing methods" J Food Sci, 67 (2002), pp. 2774–2777
They then assume that for coffee the preference increase/decrease w.r.t. temperature follows a normal distribution: "Given the statistical nature of this data, it should be
possible to represent the probability that a given fraction of the
population would prefer to drink their coffee at a given
temperature. For this purpose it was assumed that the
preferred drinking temperatures followed a normal distribution,
normalized about the mean, as shown in Fig. 5." I'll need to see the new gated paper to see if that is an acceptable assumption based upon the Lee et. al. data, but we already know from physics and psychophysics that the ratio shift between pleasurable and un-pleasurable compounds in the taste and aroma changes stepwise as the temperature crosses the boiling points for the various compounds.
But on the abstract page for the Lee et. al. article, one can see what other articles have used it as reference, one of which is "Drinking Hot Coffee: Why Doesn't It Burn the Mouth?" summarized in this Guardian article:
Essentially, those of us who drink very hot coffee are not getting burns on our lips or mouth, only when we spill it on other parts of our body.