Then a seasonal story which is now almost an environmental news classic came round once more, reminding me that the tin's contents are likely to be ever so slightly radioactive. Scandinavian reindeer eat lichen in winter, and the lichen is still contaminated from the fall-out of the Chernobyl reactor explosion over 11 years ago.
There must be some kind of meaning in this for an environment correspondent, but I'm blowed if I can find it. I'm still going to give that pate, confident that my victim would have to eat at least a tin a day through all of 1998 to be in any danger.
The trick, in reviewing the year, is to search for or to invent some meaning, some theme, which binds all the busy hopes and fears about the environment together. I have tried but failed. It has been a year of surprises and strange weather, of horrors old and new, and promises that things will get better as well as dire warnings that they must get worse. It was another year of irresolution, of old problems refusing to go away or taking on new forms.
For instance, while mad cow disease waned rapidly in cattle, new fears about BSE's ability to move into and spread through the human population arose. For instance, one of the last acts of the Conservative government was to scupper plans for an underground nuclear waste dump near Sellafield. The problem of what to do with Britain's growing mountain of radioactive waste in the long term remains.
For instance, legions of people opposed to bloodsports thought the election of a Labour government and a well-supported Private Member's Bill would mean the end of hunting with hounds. But it is not that simple.
Expect the same irresolution and confusion next year, and the year after. How we manage or mismanage our relations with nature will preoccupy us more and more over the coming quarter century, as our world is transformed by developments in genetic engineering and artificial intelligence.
Yet something momentous and enormously hopeful has been happening, almost unnoticed over the past 12 months, in the biggest environmental story of them all - human population growth. Our total number is still growing rapidly but the rate of growth is slowing. The number of extra people added on each year, the annual increment, has begun to fall.
Think of population as a graph line. Sometime this decade it stopped curving upwards more and more steeply and began to swing in the other direction. The line still points upwards, but the gradient is now lessening. The United Nations' best guess is that population is rising by 81 million each year. Ten years ago, the annual rise was 87 million. If this trend continues, global population will stabilise around the end of the next century at about 10 billion compared to today's figure of just under 5.9 billion.
This shift is partly due to horrific increases in death rates caused by the Aids pandemic in Africa. But, for the most part, it is because as standards of living rise and death rates come down, more and more women and couples in developing countries are choosing to have fewer children.
A stabilising population is fundamental for the next thousand years or so of civilisation, and it looks as if we are going to get it. Now all we need is the economic, trading and social systems to enable people everywhere to increase their standard of living. Plus the new technologies needed to allow that to happen without shortages of food, water, clean air, energy and other basic resources.
So much for the unannounced good news. Climate and weather have been the environmental bad news of 1998. England's on-off drought continued, while there were huge floods in Eastern Europe and the American Mid-West.
What seems likely to be the most damaging El Nino climate event began this summer in the eastern Pacific and is now in its prime. The drought it created may have contributed to a year of appalling forest fires which embraced much of South-east Asia in dangerous smog. Climatologists are confident that 1998 will be the world's warmest year since reliable global records began 130 years ago. Acts of God, or blunders of men?