"Dr Pang told the jury he estimated the time of death between 7 and 7.15 on the evening of August 29, 2000. This was based solely on the basis of examining the stomach contents of the murder victims - a full stomach containing potato chips and probably fish - and he noted the "distinctive" absence of the smell of gastric juices.
He did not take the temperatures of the bodies when they were found in the house, or examine them for rigor mortis. He also did not weigh the stomach contents.
Given the time of the purchase of the meals at McDonald's at 5.38pm and the journey time home, Dr Pang said the digestion process was in the early stages which led to his estimated time of death. His evidence was backed up at the trial by Professor Gilbert Barbezat, a consultant gastroenterologist, who was confident the murders happened within an hour of the last meal. Professor Barbezat had never done an autopsy but had seen more than 100 of them.
The defence case at trial was that the murders happened after 10.52pm, based on computer time evidence, and therefore Lundy had a "cast iron" alibi as he was with a prostitute a short time later at 11.36pm."
link.
How the computer came to be switched off at 10:52 in not entirely clear to me. It also sounds as if the defense might wish to reconsider its TOD.
EDT
"Dr Pang carried out the autopsies on both bodies, Amber's beginning at 7.30pm on 29th and that of Christine at 9am the following morning. He found that both stomachs were "quite full" and he was able to identify the stomach contents as a meal such as would be purchased from the fast food restaurant from which Mrs Lundy and her daughter had obtained the takeaway the evening before. He and Dr White (who accompanied him during the autopsies) noted that there was no smell of gastric juices. This indicated to Dr Pang that the digestive process had not begun. He described the duodenum in both bodies as empty which he took to be a further indication that the digestive process had not started. On the basis of these factors he made what he described as an "estimate" or an "educated estimate" that the deaths had occurred within an hour of Amber and her mother having eaten the meal. Dr White confirmed the absence of the smell of gastric juices.
The third witness for the prosecution on this issue was Professor Gilbert Barbezat, a gastroenterologist. He said that the absence of the smell of gastric juices was "very striking". He accepted that absolute certainty was not possible but he provided a "reasonably confident estimate" that death had occurred within an hour of the food having been ingested. The pathological evidence, together with the absence of gastric smell, suggested that the stomach was not yet in the emptying phase. It was in what he described as the "lag" phase. The emptying phase, in the professor's opinion, usually began within 15 to 45 minutes of the food having been eaten. While there were several factors that could alter that timing, Professor Barbezat considered that it was significant that the material findings were identical in both Amber and Christine's cases. This reduced considerably the risk of error in estimating the time of death."
Link.
BTW The brain tissue evidence reminds me of the Chamberlain case.