This list is not exhaustive; but we have included some of the most interesting stories of culinary indulgence and lavish spending. Most surprising is that some of these foods are not expensive because of their taste or health benefits – sometimes it is down to tradition or the sheer rarity.
The most expensive mushroom in the world is the white truffle. The mushroom originated in the Langhe area of the Piedmont region in northern Italy - it can grow to 4.7in/12cm diameter and 1.1lb/500g.
We do have a (more affordable) recipe for black truffles on Kitchen Geekery.
Saffron is a spice grown worldwide and famed for its characteristic vibrant yellow-orange colour and strong aromatic flavour. It has been cultivated for over 3,000 years for both culinary and medicinal uses; the spice is produced from the saffron crocus flower (Crocivus sativus), which is thought to have originated in Greece.
There have been periods when saffron has been worth more than its weight in gold. The high price of saffron comes from the flower's exacting growing conditions and a labour intensive harvesting process. A huge amount of crocus flowers are needed to produce the spice – a pound of dry saffron (0.45 kg) needing 50,000 to 75,000 flowers to make - more than an entire football field of flowers.
Popular dishes that make use of saffron are: Spanish paella, saffron sauce, French bouillabaisse, and Indian Biryani dishes.
In Western countries, the average retail price is $1,000/£500 per pound or $2,200/£1,100 per kilo.
Hailing from Hawaii - but originating in Australia, the most expensive nut in the world is the macadamia nut. The macadamia tree produces nuts only after it is 7-10 years old, and requires fertile soil and heavy rainfall. Desirable in desserts, these nuts have a very hard seed, but once open it reveals a creamy white kernel containing up to 80% oil and 4% sugar. The cost of a kilogram of these nuts exceeds $30.
Macadamia nuts are toxic to dogs.
For meat lovers Kobe beef is the holy grail of steaks. In Japan a meal consisting of this meat, prized for its rich flavour, tenderness and heavy marbling of fat will set you back around ¥13000 ($130/£65) on your credit card.
The criteria for authentic Kobe beef is very strict: the meat must come from the black Tajimi-ushi breed of Wagyu cattle, and be born, raised and slaughtered in the Hyogo Prefecture region of Japan (in which lies the city of Kobe).
Dispite reports of cows' special treatment – including being rubbed with sake (Japanese rice wine) and being fed beer, some of the less desirable aspects of their controversial living conditions have resulted in the EU banning Kobe beef imports.
Almas Caviar is the crème de la crème of caviars. The word “Almas” means diamond, and this Beluga caviar is a whitish colour. The caviar is produced by extremely rare 70-year-old albino sturgeons found only in the Caspian Sea - which is what makes it so rare and expensive.
The only known outlet is the Caviar House & Prunier in London's Piccadilly that sells a kilo of Almas caviar in a 24-karat gold tin for $25,000/£16,000. The Caviar House also sells a £800 tin for those on a smaller budget.
This rare watermelon is cultivated exclusively in Hokkaido, Japan, which only produces 10,000 of these watermelons a year. It has an unusual, even black skin with no spots, stripes, or other markings.
While some of these watermelons can sell for as little as $250, a particularly large Densuke watermelon sold for $6100 in 2008 at auction.
Hailing from the islands of Sumatra, Java, and Sulawesi in the Indonesian Archipelago, and the Philippines, Kopi Luwak coffee is made from coffee beans digested by a small catlike animal called the Asian Palm Civet.
The enzymes in the animal's digestive tract make the beans less acidic, dramatically improving the coffee's flavour. Only 500lbs/225kg are produced every year, making it very rare, and its flavour is (according to coffee connoisseurs), of unrivalled mildness and smoothness.
Up to $600/£365 per pound, or $1200/£730 per kilo.