I believe the deaths we see in the news are being caused mostly by distillers who don't really know what they are doing. But, is it a real concern? That, I'm still not exactly sure of. So, does rice have pectin? Some sources indicate yes. So it appears you may be correct that pectin plays a critical role in methanol production. The US study also states: "Methanol is produced during fermentation by the hydrolysis of naturally occurring pectin". And with many (most?) yeast strains, the ethanol limit is even lower than that, maybe 8-9% for a lot of them. This also makes sense in that most naturally fermented beverages cannot exceed about 12-14% ethanol content - the yeast just gets too tired before it can ferment any higher than that.
Yet in many instances where death has occurred, the methanol content in these beverages was found to be as high as 16-25%! This leads me to believe that either foul play was involved, or unskilled distillers made a bad product, leading to many or most of the methanol-related deaths, considering that natural undistilled fermentations appear to be limited to around the 0.2% level. The US government for instance limits methanol concentration to a maximum of 0.1%, which is highly conservative, and approximately matches the blood-alcohol toxicity level for methanol of approximately 0.10-0.15%. Some governments like the EU actually find these amounts to be acceptable, while most other governments do not. The concentration of methanol found in these fermented beverages ranged from 0 to about 1.5-2% at the most. This study found that fermentations of the following ingredients can sometimes lead to relatively high quantities of methanol in fermented beverages: A quick Google search led me to a study by the US National Library of Medicine National Institutes of Health. This is the first I've really looked into this. While bacterial contamination could conceivably produce significant amounts of methanol, the conditions for this to occur are so far removed from a normal fermentation that you will definitely spot it, starting with the odors of the bacterial decomposition that produces the methane required, and the fatal levels of oxygen you would have to had introduced into your fermenter. The horror stories of methanol-containing booze wiping out entire parties are the result of mixing methanol into beverages intended for human consumption (either accidentally or deliberately).
aerate/oxygenate your must/wort/wash prior to pitching yeast and keep it anaerobic thereafter) you have NO chance of methanol occurring in more than trace quantities.
avoid bacterial contamination) and manage your oxygen levels (ie. The bottom line is that as long as you observe proper sanitation (ie. This requires the presence of methane (a byproduct from bacterial decomposition) and oxygen.
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