17:03 Sep 29, 2016
I must admit, I never thought of salmon as being transparent in the first place! But I've now seen enough recipes to convince me that 'opaque' really is the word they use.
From personal experience, I can say that salmon cooking in the oven does, after a while, turn dull or lose its gloss.
So perhaps it's really the other sense of 'opaque': not 'non-transparent' but 'dull', i.e. lacking gloss or lustre. (A search for 'opaque' as a synonym of 'dull' reveals some contexts where 'opaque' is used in this sense).
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