Malta's white olives

Once, when the Knights of the Order of Saint John, also known as the Knights of Malta, occupied Malta from 1530 to 1798, plump, bone-white olives were known across Europe as perlina Maltese (Maltese pearls).

The white olive is just one of hundreds of varieties of the European olive (Olea europaea). One of its botanical subclassifications is Leucocarpa, from the Greek leukos (white) and karpos (flesh or pulp). White olives not only grow on Malta, but can also be found in southern Italy, Morocco, Libya, Greece and Portugal, where they often go by local names, including bianca (Italian 'white'), biancolilla or cannellina (after their resemblance to white cannellini beans). Researchers who have studied the white olive’s genetics say that its unique color, or lack thereof, is simply a quirk of nature.

White olives originate from mutations affecting the production of anthocyanins, the pigments typical of what you see in conventional ripened olives, so that at the full ripening stage they do not become black.

White olives are a rare sight. They are seldom commercially available today and, historically, why they have been valued ornamentally and even religiously. In the southern Italian region of Calabria, for example, white olive trees in the gardens of churches and monasteries provided sacramental oil used to anoint high-ranking church officials and Byzantine emperors.

Oil from white olives resembles that from black and green olives, yet it has a much shorter shelf life. That is because it has comparatively low levels of bitter-tasting antioxidants that also make for a natural preservative. Therefore, white olive oil tastes sweeter than many other olive oils.

Italian knights introduced white olives on Malta in the 14th or 15th century. The bajda (Maltese 'white') is probably an Italian cultivar brought from southern and central Italy as an ornamental plant. That's partly the reason why today no wild white olive trees in Malta exist and only a few old, individual trees remain.

[The oldest white olive tree. Designated 'national treasure']

However, on Malta, the number of old trees was down to precisely three when Sam Cremona first set eyes on one in 2010. “It was in a nunnery, in a garden that once belonged to the knights,” said Cremona. At first, he thought the startlingly white olives might be diseased or albino aberrations. However, after taking some to an olive conference in Spain, he learned that Malta possessed a rare treasure.

“They told me, ‘Ah, we know about these white olives. We used to have them, but we don’t have them anymore,’ because they were a variety that had disappeared in Spain, where they were known as ‘Maltese olives,’” Cremona stated. Of the island nation’s 12,000 olive trees today, only 70 are white olive trees.

The taste of the white olive is described as delicious—bitter top, citrusy middle, with a briny finish.