milk was a serious health threat, particularly to children. We had no mechanical refrigeration and so there was a lot of spoilage problems.
Steven Johnson: How humanity doubled life expectancy in a century | TED · TED
How native speakers pronounce “refrigeration”
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milk was a serious health threat, particularly to children. We had no mechanical refrigeration and so there was a lot of spoilage problems.
Steven Johnson: How humanity doubled life expectancy in a century | TED · TED