Lemon and Lime - a Double Act?
Citrus Fruits with Sweet & Sour Notes
Although both are well known as citrus fruits, they have different origins and qualities which merit separate discussion. While neither is used extensively on its own within desserts due to the high citric acid content, they find use as natural flavouring agents and preservatives. The difference in colour is a poor distinguishing feature since unripe limes change to orange and then yellow if allowed to ripen on the tree. As a result, the familiar green limes in our shops contain significantly more citric acid than lemons!
The Early History of Lemons
Lemons (Citrus limonia) originate from the subtropics, while limes (Citrus aurantifolia) belong to tropical regions. The former only reached the Mediterranean region from India towards the end of the 1st century AD, with help from the Romans who illustrated frescos and mosaics at Pompeii with images of lemons. (1). However, they remained as curiosities for several centuries, as no-one realised their potency as a culinary or herbal ingredient. It was the Arabs who established the fruit within Italian orchards around the 4th century and also encouraged its spread eastwards towards China. As lemons became more abundant, so did their uses in the kitchen with syrups, preserves and garnishes proving popular, particularly with fish dishes.
It was in 1493 that Christopher Columbus first introduced them to the New World, risking outbreaks of scurvy in the process. Unknown to the crew, their precious cargo held the cure for the disease, but this was not established until the British Naval Surgeon, James Lind endorsed the treatment within his Treatise on the Scurvy in 1753. It wasn’t until 1933 that the Hungarian biochemist Albert Szent-Gyorgi first isolated vitamin C from fresh paprika left over from his lunch, and fed the extract to vitamin-deficient guinea pigs in his laboratory.
The Early History of Limes
Limes can be traced back to Malaysia, but early records fail to distinguish them from other citrus fruits, until medieval times when the nomadic movements of the Arabs once again transported them towards Europe. Unfortunately, they did not to thrive in the cooler climate, and needed further help from Christopher Columbus and others to establish them in Central America, especially Mexico.
There are several documented hybrids, including Citrus latifolia - a seedless fruit originally from the Orient and grown on a limited basis in Florida and California. Sweet limes (Citrus limettoides) are ancient hybrids from Palestine and India, where they are enjoyed as a juicy alternative, more palatable because of the lower acid content. In contrast, dried limes are added to stews and curries in many Asian and Middle Eastern dishes, where they add a characteristic musty, sour flavour to the ingredients.
Nutritional comparison and culinary uses.
- Both lemons and limes have a high vitamin C content (37 and 53mg/100g respectively),
- low calorific values (28kcals/100g),
- high potassium, calcium and fibre content - typical of most fruits and vegetables,
- high beta-carotene (Vitamin A) content arising from the yellow pigment,
- high bioflavonoid (antioxidant) content - from the pigments concentrated in the pulp and peel, which is notably absent from lemon flavoured drinks and cordials.
- Their culinary value exploits their pectin content for jams, sour flavour and essential oil aroma for desserts and citric acid content for preventing the enzymic browning of freshly cut fruit and vegetables (2).
Limoncello - a squeeze too far?
Extracting essential oils from lemons is a precise science, requiring absolute alcohol (96% ABV) to obtain the maximum quantity of oil from the peel. Using vodka (40% ABV) as the solvent will result in a vastly inferior extraction rate if you are trying this at home. The variety of lemon used and the climate, soil and time of harvest all impact on the flavour - which is far superior to anything you can buy in a supermarket.
It is worth travelling to the Amalfi coast to obtain the best lemon liqueur first hand, but remember to drink it thoroughly chilled - according to local custom. At room temperature, it tastes like washing up liquid. Served up as a "Hot Toddy" - and you've ended up in the wrong country!
References
- Davidson A. (2008) The Penguin Companion to Food. Penguin Books.
- Ensminger A. et al (2003) The Concise Encyclopaedia of Foods and Nutrition. CRC Press.
Lemon & Limes
|
What do you think about this article?
More in Health & Wellness
Latest Articles