MY HEART BLEEDS
On a Baja Web forum, I posted that provide evidence for why this practice should be done?
James Hamada Los Angeles, California
Contrary to one widely held belief, blood doesn’t normally carry bacteria that would be involved in spoilage — if it did, fish would have chronic infections throughout their lives. However, blood might give fishes’ flesh a strong, gamy flavor if it’s allowed to remain in their muscles after death. This is especially true of strongly swimming fishes that have large amounts of highly vascularized red muscle. Thus, in most species, the reason for draining blood is to prevent the blood from altering the taste of a fish’s flesh.
Some fish, such as tunas, are heterothermic, meaning their body temperatures are well above that of the surrounding seawater but still vary as the water temperature varies. The physiological basis for the elevated body temperatures involves the arrangement of blood vessels that allows heat transfer between vessels, allowing more heat to remain inside the fishes’ bodies. In these species, removing the blood allows a fish to cool down more rapidly and helps prevent it from spoiling or “cooking” from its own body-generated heat.
Finally, blood can serve as a growth medium for bacteria, so once it leaves a fish’s circulatory system, it can promote spoilage — especially if a fish isn’t properly cooled. The best way to ensure having the highest quality:
• Open the cavity that contains the heart (the pericardial cavity, located in the fleshy space below the back part of a fish’s gill covers) and cut the large vessel coming out of the front of the heart.
• Let the blood drain from the
• Remove the fish’s gills and viscera. • Lightly rinse the fish in salt water to remove as much remaining blood as possible.
• Then pack the fish in ice.
With tuna, it’s also a good idea to sever the spinal cord behind the head to prevent nerve impulses from reaching the fish’s muscles, which can generate additional heat and help promote spoilage.