Where did Seignalet get that arbitrary figure of 110C for the creation of Maillard molecules? I suspect the figure is much lower, given that enzymes(which are proteins) already start being affected c.40C and destroyed at 47C and upwards.
Let's recall a little bit physics or chemistry.
Denaturation of proteins or enzymes takes places at fairly low temperatures indeed, for instance 50 °C (but also sometimes obviously at much higher temperatures in bacteria capable to live in deep see boiling water niches !). Denaturation of proteins means a change in configuration and structure in 3-dimensional space of a macromolecule, i.e. a big molecule made here of a long string of typically hundreds of aminoacids. This prevents the protein as an enzyme to remain active in the organism's biochemistry but does not render it toxic by itself if one eats it. In this respect it is important to become aware of the fact that all proteins are denaturated in the acid stomacal environment upon digestion and/or hydrolysis. Toxicity is brought about only when the aminoacids themselves are damaged or reacted with other molecules by heat and this needs usually markedly higher temperatures than 50°C. Notice that otherwise a simple fever would wreak havoc in the organism's biochemistry.
Formation of Maillard molecules or other culinary toxins similarly needs higher temperatures to take place in sizable or harmful quantities. This is because, as aminoacid destruction or damage or racemization, these chemical reactions are non-enzymatic thermally activated reactions that are very slow at body temperature but become very rapid about 100°C or higher.
To give just an idea of the reaction rates involved typically:
While in given quantity of a food we get for instance 1 molecule of a typical Maillard product formed per second when left at 15°C, there are 40000 of them formed per second at 90°C and 10 millions of them formed per second at 180°C. That's thermal activation...In other words one gets about 70000 times (10^7 x 30 / (60 x 24 x 3) more AGE's after cooking 30 minutes at 180°C than when left raw at 15°C for 3 days.
Since from a darwinian point of view we had ample time to adapt to it, one may imagine that we are capable to deal easily with the tiny amount of AGE's produced in food left at room temperature even after several hours or days or months. Yet with 70000 times more and 2 meals a day for several tens of years our detoxination mechanisms might well be progressively overwhelmed and the organism more and more poisened. This is obviously in line with the fact that the health problems of civilized "cooked" people usually appear and increase upon aging only.
So, to come back to Seignalet, from a technical point of view 110°C is certainly not a limit with no heat generated toxin formation below. There are just one or two orders of magnitude less than at 180°C. Best adaptation of our or other species is for no heating at all. AFAIK Seignalet knew that of course but just told his patients that the lesser evil for those of them unable to eat their meat or fish raw was to cook it at temperature below 110°C.
