The test was done. Only 9 skeptics in a room of almost 40 were willing to participate. Here are the results and the procedure:
People got an answer sheet with the order to eat the samples in, randomized at the top of the sheet. I cooked 3 samples of burger in three pans at the same time on my stove. They all got the same amount of light salt and pepper. They were all cooked for the same length of time over the same heat. All were cooked as chopped burger the way I cook burger for tacos or spaghetti rather than patties. I then put the samples into cups designated for hot drinks and put those cups into an insulated box. I went straight to the meetup and the samples did not need reheating. I did not participate because it didn't work out that I was blinded. And while it was not technically double blinded, the participants had an answer sheet, I was not an interviewer adding any kind of subjective influence to the answers.
It is possible the samples with LFTB had different amounts of LFTB as they were purchased after the controversy was in full swing. So it cannot be assumed that the burger with 4% fat had more LFTB than the sample with 7% fat. It can be said both had LFTB, just not how much.
The questionnaire asked for 3 possible ratings of texture, flavor, juiciness and preference to disguise the fact texture was the main quality being investigated. The other answers added interest to the findings but I was looking for texture evaluations.
I used 'tender', 'chewy' and 'gristly' as options knowing people describe texture in different ways. The main idea was, did the texture differ, not how did people describe the difference.
Sample 1 was 7% fat with LFTB.
1 person found it tender, 6 found it chewy and 2 found it gristly.
Sample 3 was 4% fat with LFBT.
4 people found it tender and 5 found it chewy.
Sample 2 was 7% fat and contained no LFTB.
6 people found it tender and 3 found it chewy.
So with LFTB: 28% tender; 61% chewy; 11% gristly.
Without LFBT: 67% tender; 33% chewy; 0% gristly.
If you just compare the 7% with to the 7% without:
With LFTB: 11% tender; 67% chewy; 22% gristly.
Without LFBT: 67% tender; 33% chewy; 0% gristly.
It can be concluded that in this pilot study, the hamburger texture without the LFTB had a significantly different texture than the hamburger with LFTB.
If you add my unblinded assessment I found both samples 1 & 3 gristly and 2 tender.
As for preference, some people preferred the burger with LFTB and that did not surprise me nor affect my issue, that labeling should have included information that LFTB was added.
Sample 1: 1 person rated as "best", 3 as "middle" and 5 as "worst".
Sample 3: 2 people rated as "best", 6 as "middle" and 1 as "worst".
Sample 2: 4 people rated as "best", 3 as "middle" and 2 as "worst".
While there were 9 assessments of best, middle, worst for each sample, some people gave equal ratings to some of the samples. I.e. best has 7 votes, middle has 12 and worst has 8 total votes.
The flavor options were 'good', 'fair', & 'bad'.
Sample 1: 0 good; 6 fair; 3 bad.
Sample 3: 5 good, 4 fair; 0 bad.
Sample 2: 3 good, 5 fair and 1 bad.
Some people preferred the burger with LFTB. The people selling it shouldn't be afraid of labeling it.
Juiciness options were 'good', 'fair', & 'bad'.
Sample 1: 1 good; 3 fair; 5 bad.
Sample 3: 2 good, 4 fair; 3 bad.
Sample 2: 1 good, 5 fair and 3 bad.
The method of preparation may have resulted in extra dryness of all the samples.