Posted by: Footler PJ20 MAR 2013
William Bligh is probably best known for commanding HMS Bounty on the voyage to Tahiti that led to the infamous mutiny in 1789 and his subsequent 3,600-mile voyage to Timor in an open boat. During 1791–93 Bligh returned to Tahiti to complete his original objective by successfully transporting breadfruit trees to the West Indies.
On his homeward voyage from Jamaica, Bligh carried specimens of the ackee tree for study at Kew, where the tree was named Blighia sapida in his honour. However, the tree is not endemic to the West Indies. It originated in West Africa and was probably carried across the Atlantic by slave traders.
Ackee mixed with salted cod became a staple food for the slaves. Despite its origin the combination is still considered Jamaica’s national dish.
The fruits of B sapida must be harvested only when they are fully ripe. At this stage the bright red or yellow-orange fruits split open to reveal three large, black, glossy seeds that are surrounded by creamy-white flesh, the aril, which is the only edible part of the fruit.
Unripe ackee fruit contains a toxic, non-proteinogenic amino acid, hypoglycin A, that reduces blood sugar to extremely low levels. Eating the unripe fruit causes drowsiness, repeated vomiting and dehydration. In acute cases, the muscular and nervous systems may collapse leading to coma and death. This is known as toxic hypoglycaemic syndrome or Jamaican vomiting sickness.
In the ripe fruit the hypoglycin A is mostly converted to hypoglycin B, which concentrates in the seeds and leaves the flesh safe to eat after cooking.
Research into using the ackee fruit as a medicinal food to help control blood sugar levels in diabetes has been limited to studying modifications of the chemical structure of hypoglycin A. This is because the unripe ackee fruit poses a serious health risk whereas the ripe flesh does not contain enough hypoglycin A to provide any benefit.