Dried orange peel

• chenpi陳皮

  Mandarin

  Literally "aged peel", and the word carries the ageing in it: fresh dried peel is not chenpi to a Chinese cook, and a shop selling chenpi is selling something that has been kept deliberately for years.

• gwo pei

  Cantonese — Guangdong

  Everyday Cantonese usage covers dried citrus peel generally; the graded Xinhui product is named and priced separately.

• écorce d’orange amère

  French

  European usage means bitter-orange peel, a different species from the mandarin peel of the Chinese trade and used for different things.

Bitter first, aromatic second, and not sweet at all. The bitterness comes from flavonoids concentrated in the pith and inner peel and is the point rather than a defect: it is what cuts through fat in a braise and what balances sugar in a bake. Aged peel is rounder and less sharply bitter than young.

Young dried peel smells brightly of orange with a bitter edge. Aged peel smells much less of fresh citrus and much more of marmalade, dried apricot and something faintly medicinal — the difference is not intensity but character.

Fresh-dried mandarin peel is bright orange with a pale inner face. Aged peel darkens progressively to deep brown-red, and the colour is one of the things a buyer reads as age.

Hard, brittle and curled when dry; softens to leathery on soaking and to tender after long simmering. Aged peel is more brittle than young.

• Limonene — The bright citrus top note, dominant in fresh and young peel and the first thing lost on drying and ageing. Its decline is most of what ageing does.(what limonene is)
• Polymethoxyflavones — The bitter, faintly medicinal fraction that remains and comes forward as the volatiles go. They are non-volatile, which is why old peel is more bitter relative to its aroma rather than simply weaker.

Soak whole peel in warm water for ten to twenty minutes until it is pliable. If a milder result is wanted, scrape away some of the white pith, which carries most of the bitterness — this is the main lever a cook has over how assertive the peel will be. Add it to the pot early for a long braise and taste as it goes, lifting it out once the bitterness is where it should be. For frying, add it after the other aromatics and keep it moving: it scorches faster than chilli and goes acrid rather than merely dark. Use less than instinct suggests. A piece the size of a thumbnail is enough for a pot of soup.

A bitter aromatic rather than a citrus flavouring, and used where a dish needs cutting rather than brightening. In Cantonese cooking a small piece goes into soups, congee, steamed pork and red-bean sweet soup; in Sichuan cooking it is fried with chillies and used in braises, most visibly in orange-peel beef. It is one of the optional components of five-spice. In Europe the bitter-orange peel flavours Christmas baking, mulled wine and Belgian witbier, where it appears with coriander seed. Nowhere is it used to make a dish taste of orange — that is what fresh zest is for.

• infusing — The standard treatment. Soaked in warm water to soften, then simmered in the dish and often removed. Long simmering extracts the bitterness fully, which is wanted in a red-braise and not in a delicate broth.
• grinding — Ground into five-spice variants and rubs. Ground peel gives its bitterness immediately and evenly and cannot be retrieved, so it is used in smaller quantity than a whole piece would be.
• frying — Fried briefly in oil at the start of a Sichuan dish alongside chillies and peppercorns, which develops a toasted, marmalade character. It scorches quickly and turns acridly bitter, so it goes in after the aromatics rather than with them.
• boiling — Holds up through hours of braising. Unlike most aromatics it becomes more prominent rather than less, because the bitterness is non-volatile and concentrates as liquid reduces.

Snap a piece. Good dry peel is brittle and cracks; peel that bends without breaking has taken up moisture and should be dried before it is stored further. Then smell it: young peel should smell of orange, and old peel should smell of marmalade and dried fruit — what neither should smell of is musty, which means mould.

• Pliability rather than brittleness, indicating moisture uptake
• A musty or cellar-like smell, which is mould and is not the ageing character
• Visible white or green growth, particularly in the curl of the peel where air moves least
• No smell at all on scraping the surface

• Loss of limonene and the volatile citrus fraction, which is decline in ground peel and deliberate maturation in whole aged peel.
• Moisture uptake in humid storage, leading to softening and eventually to mould
• Colour fading in light, which matters commercially because colour reads as age

Whole, and it is not a close call. The whole piece can be lifted out of the pot, which is the whole technique for an ingredient whose contribution is bitterness — the cook tastes and decides when there is enough. Ground peel commits everything at the start and an over-bitter braise cannot be walked back. Whole peel also keeps for years where ground fades in months, and it is the form the Chinese trade actually sells.

• Large curled pieces rather than small chips, which are offcuts and often a mixture of origins.
• Brittle enough to snap, not pliable — pliability means moisture.
• A clear smell on scraping the inner face: orange in young peel, marmalade and dried fruit in aged.
• For chenpi, a stated origin and age, understanding that neither can be verified at the counter and both carry a large premium.
• No musty note anywhere, which is the one disqualifying smell.

Xinhui chenpi is graded by stated age in years and by origin, and the price curve is steep. Ordinary Chinese-grocery dried peel is ungraded and perfectly usable for cooking. European bitter-orange peel is sold as a commodity by cut — strips, chips or ground — with no age dimension at all, because it is not aged.

Rutaceae

A small evergreen tree with glossy aromatic leaves and white flowers. The fruit peel carries oil glands visible as dimples, and it is those glands rather than the flesh that make the peel a spice.

Citrus originated in a broad arc across South and Southeast Asia and southern China. The mandarin peel trade is centred on Xinhui in Guangdong, and the bitter-orange trade on the Mediterranean and, historically, on Curaçao — from which the liqueur and the trade name for the peel both come.

• CN (Xinhui, Guangdong) — origin. The origin of graded chenpi, where peel is aged, dated and traded much as a wine region trades vintages.
• ES — major producer. Seville oranges for the European bitter-peel and marmalade trades.
• CW — historic producer. Curaçao, whose bitter oranges gave the liqueur and the trade name for the peel used in brewing.
• US — notable producer

Peel is a by-product of fruit harvest and is taken from ripe fruit. For chenpi the fruit is picked at particular stages and the peel removed in a characteristic three-lobed pattern that survives drying and is used to identify the product.

1. Peeling — The peel is removed in large pieces rather than shredded, traditionally in three connected lobes for the Xinhui product.Why: Large intact pieces dry evenly, keep better and can be identified as to origin and cut.
2. Drying — Sun-dried until leathery and then hard.Why: Stabilising a peel with high moisture and high sugar.
3. Ageing — For chenpi only: stored for years in controlled dry conditions, brought out and re-sunned periodically, and dated. Three years is a commercial minimum for the graded product and much older peel is traded at a considerable premium.Why: The ageing is the product. Volatile limonene declines and the remaining flavonoids and heavier aromatics dominate, which turns a sharp citrus into something deeper and less bright.

Xinhui chenpi is graded by age, stated in years, and by the cut and origin of the peel. Age claims at retail are not independently verifiable by a buyer, and the market carries a substantial premium for old peel — which is the standing invitation to misrepresent it.

The commercial risk is age and origin rather than substance: peel from outside Xinhui sold as Xinhui, and young peel sold as old. Sweet-orange peel substituted for mandarin is the other common swap and is detectable by smell, being sweeter and much less complex.

Subtropical, frost-sensitive, and needing a dry period at ripening. Peel quality is affected by the same growing conditions that affect the fruit, which is why origin claims for chenpi are taken seriously in the trade.

Dried citrus peel has been used as an aromatic in Chinese cooking and medicine for well over a thousand years, and the practice of ageing it deliberately is old enough to have produced a graded regional trade at Xinhui. In Europe the relevant peel is a different species and a different story: bitter oranges reached the Mediterranean through Arab agriculture before sweet oranges did, and their peel became a baking and distilling ingredient, giving both marmalade and the orange liqueurs named after Curaçao.

Two largely separate trades. The Chinese aged-peel trade is a premium regional market where age and origin set the price; the European bitter-peel trade is a commodity by-product of the Seville orange and marmalade industries.

Chenpi is a standard herb in Chinese medicine, used for digestion and for what the tradition describes as damp and phlegm. This is a statement about the tradition and about how widely the ingredient is stocked; SpiceHQ makes no health claim, and the medicinal grade and the culinary grade are the same peel sold in different shops.