With improvements in transportation and handling, it is now easier than ever to get hold of exotic ingredients at wholesale markets. Chefs are increasingly sourcing more unusual varieties of vegetable to add flavour and texture to dishes, especially those with an Asian influence.
Alfie Ooi, head of sales and marketing at New Covent Garden Market wholesaler Kim Guan Choong, said: "Globalisation continues to expose us to more cultures and cuisines, and chefs are constantly striving for novel and unique dishes reflecting these expanding culinary experiences. We have developed a strong network of growers and importers to give chefs access to exotic ingredients from every producing country in the world.
"We continually develop new grower relationships to bring these exotic items to our chefs' fingertips, and overcome the ever- growing challenges of global health and safety standards and ethical trading. This makes it all the more rewarding when we see chefs realise their ideas on the plate."
Continuing our tutored tasting series, we gave three chefs the opportunity to try a variety of exotic vegetables provided by Kim Guan Choong. Here Alfie Ooi guides us through a selection.
Properties Great depth of flavour, both fruity and spicy, but milder than their dried black counterparts.
Usage Adds great depth of flavour to curries. Make a paste for shallow frying, or shallow fry whole in a curry.
Notes Green peppercorns are the unripe berries of a tropical vine.
Properties Small, plum sized, light green and white aubergines.
Usage One of the few aubergines that can be eaten raw with a nutty taste. Fresh and sweet in their natural state and mostly used in curries, particularly Thai Green Curry.
Notes Quarter and cook for 10-15 minutes in curries.
Properties Carrot coloured root, much like ginger, although smaller and less knobbly.
Usage More usually used in its dried form, the fresh root gives great flavour and colour when grated into dishes, and only a small amount is needed.
Notes Wear gloves when handling, it stains everything it touches!
Properties Tubular stems and long soft leaves, similar to wild spinach. Slight peppery taste, similar to watercress.
Usage Generally used very simply in stir fries, but could also be used raw in salads.
Warning Not all Morning Glory is edible, better to order from a specialist supplier than go foraging for this one!
BIRDS EYE CHILLI
Properties Small, hard and tapered chillies, can be red or green. Very Hot.
Usage Use with caution. The heat of Birds Eye Chilli can vary with each box, but the heat can overpower other flavours.
Notes Sometimes called Thai chillies, but is actually Mexican in origin.
Properties Foot long green beans with a firmer texture and slightly nuttier taste than British grown green beans.
Usage Can be eaten raw.
Notes These take quite a lot more cooking than Western green beans.
Properties Small green aubergines, no bigger than grapes. A slightly bitter flavour that bursts in the mouth.
Usage Versatile ingredient that can be crushed for use in chutneys, relishes, and dips as well as in curries, stir fries and soups.
Notes Need cooking out to reduce the firm texture.
KRA CHAI (WILD GINGER)
Properties Thin finger-like roots, more moist and fragrant than normal ginger.
Usage In curry paste or light stir fries, can also be used raw in a salad.
Notes Doesn't keep as well as western root ginger as it contains more moisture.
Properties Knobbly, light green and about the size of a small sweet potato. A shiny skin and white flesh with brown pips. Tastes sweet with a bitter aftertaste, as the name suggests.
Usage Excellent pickled or deep fried.
Notes Often called a Bitter Melon. Renowned in Asia for its health properties and proven to lower blood glucose levels in diabetics.
WHAT THE CHEFS SAID
Head chef, Ganapati, London I use green peppercorns in fish curries or to make a paste for shallow frying. They have a great depth of flavour.
We use an alternative to the apple aubergine in India - small purple ones called Ravaya in Hindi. They are essential in Indian cooking.
When I cook with Morning Glory I often use it in stir fries with coconut to balance the pepperiness.
Chef/director, the Palmerston, London The snake beans hold together better than UK beans but they take more cooking. You could eat them raw or stir fried and they could be used in a Thai dish.
Pea aubergines are very unpleasant when raw - they are more bitter and astringent than normal aubergines. They are great in a curry, however, as they pop in your mouth.
We cook bitter gourd with lamb and you can also cook it with tamarind in a curry to add sweetness and balance out the bitterness.
Head chef/owner, the Begging Bowl, London
We have used green peppercorns in a dish with wild ginger and pork, and they are great to cleanse the palate.
Buying turmeric fresh gives a fantastic flavour and colour - just grate it straight in. You don't need much, either.
Thai cooking doesn't really have any recipes - it's always more of a guide as ingredients are less standardised, and this is where the chef's skills come in. We are constantly adjusting the amount of palm sugar and chilli as we go.
Exotic veg can be an expensive part of the menu but it is these specialist ingredients that contribute to the subtelty and authentic aromas of ethnic cuisine.