To assess the quality of fresh fish and seafood, there are a few simple things to look for: Fresh whole fish should have bright, clear eyes; skin should be shiny, firm and elastic to the touch, gills should be red not brown, and if gutted, the cavity should be clean.o assess the quality of fresh fish and seafood, there are a few simple things to look for: Fresh whole fish should have bright, clear eyes; skin should be shiny, firm and elastic to the touch, gills should be red not brown, and if gutted, the cavity should be clean.
Drying oil. A drying oil is an oil that hardens to a tough, solid film after a period of exposure to air. The oil hardens through a chemical reaction in which the components crosslink (and hence, polymerize) by the action of oxygen (not through the evaporation of water or other solvents). Drying oils are a key component of oil paint and some varnishes.
Walnut Oil: an oil early favored by oil painters for its drying properties, since it dries quickly and evenly throughout. Slightly aged nuts produce higher quality (purer) oil. In earlier centuries difficulties in extraction and storage impaired its usefulness as a medium, making it less popular than linseed oil.