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smokysourspicy

Penicillin

Blended Scotch, honey-ginger syrup and lemon, topped with a peaty Islay float — smoky, spiced and citrus-sharp.

Difficulty
advanced
Prep time
6 min
Strength
22.8% ABV
Glassware
Rocks glass
Base
whisky
Serves
1

Ingredients

  • Blended Scotch whisky
    50ml
  • Fresh lemon juice
    20ml
  • Honey syrup
    15ml
  • Ginger syrup

    Fresh ginger syrup gives the best heat; not on the standard pantry list, but essential to this drink

    10ml
  • Islay Scotch whisky

    Floated on top after straining, not shaken in

    8ml

Garnish: Candied ginger, Lemon peel

Scale for a party

Method

  1. Add the blended Scotch, lemon juice, honey syrup and ginger syrup to a shaker with ice.
  2. Shake hard for around 12 seconds.
  3. Strain into a rocks glass over fresh ice.
  4. Float the Islay Scotch on top by pouring it slowly over the back of a bar spoon.
  5. Garnish with candied ginger and a lemon peel.

Equipment

Don't have everything? Here's what works instead.

  • Cocktail shaker

    Household swap: A secure jar or bottle with a tight-fitting lid, shaken firmly.

  • Hawthorne strainer

    Household swap: A slotted kitchen spoon held across the shaker opening.

Missing an ingredient?

Each swap below says what it changes and how to correct for it, so you can decide whether you are making this drink or a neighbouring one.

  • Instead of Islay Scotch

    Best substitute: Blended Scotch

    This is the modifier in this drink.

    Flavour impact: Loses the smoky top note entirely; the drink becomes a straightforward honey-ginger whisky sour.

    What changes

    Expect less bitterness and less intensity. Still a good drink, and a slightly different one.

    Bitterness ↓
    Losing bitterness makes the drink rounder and more approachable, and takes away the structure that stopped it tasting like squash.
    Intensity ↓
    A milder ingredient gets buried by whatever else is in the glass, and the drink loses the thing it was named for.
    Character
    you lose smoky, peaty, briny and intense, and you gain honeyed, smooth, light smoke and balanced. Numbers can't see this: two ingredients can be identically sour and still smell nothing alike.

    To correct for it

    • A dash of bitters restores some of the backbone without changing anything else.
    • Increase the measure, or accept a gentler drink and reduce the components competing with it.
    Moderate confidenceWorkable as a drink, but changes the character the recipe is built around.Shifts the drink

Make it better

  • A little Islay Scotch goes a long way for the float — 8ml is usually plenty of smoke.
  • Make your own ginger syrup with fresh ginger if you can; it makes a bigger difference here than almost any other ingredient swap.
  • Strain into fresh ice, not the ice used for shaking, so the float sits cleanly on top instead of clouding into melted shaker ice.
  • Express the citrus peel by pinching it, skin-side down, over the drink before dropping it in — this releases aromatic oils across the surface.

Rescue this drink

Not smoky enough
Float a little more Islay Scotch, and pour it slowly so it stays on the surface rather than mixing through.
Too sweet
Reduce the honey syrup to 10ml.
The float sinks instead of sitting on top
Pour it more slowly, over the back of a spoon, onto fresh ice rather than directly into the liquid.
You cannot smell itgeneral guidance
Most of a drink's aroma is on top of it, not in it. Squeeze the peel skin-side-down over the surface before dropping it in — the oil should visibly spray. A twist placed in the glass without being expressed contributes almost nothing. Aroma also fades fastest of anything in a drink, so garnish at the moment of serving rather than in advance.
Too stronggeneral guidance
Stir or shake for a little longer to add dilution, or add a splash of chilled water. This is a spirit-forward drink by design, so some strength is expected.
Too sourgeneral guidance
Add a little more sweetener (simple syrup or the cocktail's usual sweetening ingredient), a small amount at a time.
Served too warmgeneral guidance
Chill the glass, ice and every ingredient ahead of time — a warm pour is the fastest way to lose a cold drink's balance. For one serving, there's no real fix beyond rebuilding it properly chilled; for a batch, keep everything refrigerated until the moment of serving and add ice last.
Over-diluted (tastes watery)general guidance
Likely shaken too long, or with too much ice surface area. For one serving there's no fixing it after the fact — rebuild with fewer, larger ice cubes and a shorter shake. Planning a batch? Shorten the ice-contact time across the whole round, not just this glass.
Under-diluted (tastes harsh or too concentrated)general guidance
For one serving, stir in a few drops of chilled water to open it up. For a batch, extend the shake time slightly on the next round.
No cocktail shakergeneral guidance
A secure jar or bottle with a tight-fitting lid, shaken firmly.
No cocktail strainergeneral guidance
A slotted kitchen spoon held across the shaker opening.

Make ahead & storage

Batch the base, finish at serving

Batch the 4 stable components days ahead and add fresh lemon juice when you pour.

Add about 27% water to the batch to replace what the ice would otherwise contribute, or it will pour noticeably harsher than a fresh one.

Fresh lemon juice:
Fresh citrus loses its aroma within hours and turns dull. Squeeze it on the day.

What it tastes like

The taste, and what drives it

off-dry, sharp, light — a sour-structured drink served over ice.

Off-dry

Dry → Sweet

Sweetened enough to take the edge off without reading as a sweet drink.

What drives it: Honey syrup — carries the most sugar into the glass.

Sharp

Soft → Sharp

Properly sharp. This is the axis the drink is built on.

What drives it: Fresh lemon juice — supplies the acidity.

Faintly bitter

Gentle → Bitter

A bitter edge you would only notice if you looked for it.

What drives it: Blended Scotch whisky — provides the bitterness.

Light

Light → Rich

Light-bodied. It refreshes rather than satisfies, which is usually the intention.

What drives it: Blended Scotch whisky — adds most of the weight.

Very bold

Delicate → Bold

Very bold — concentrated, and served small for that reason.

What drives it: Blended Scotch whisky — is the most concentrated thing in the glass.

What you smell first

  • Citrus peelLeadsBefore the first sip

    From Fresh lemon juice, Lemon peel

  • Smoke

    From Blended Scotch whisky, Islay Scotch whisky

  • Oak

    From Blended Scotch whisky, Islay Scotch whisky

  • Floral

    From Honey syrup

  • Ginger

    From Ginger syrup

Aromas marked as sitting above the drink reach you before the first sip — skipping that garnish changes the drink more than its size suggests.

How it was worked out

Each reading comes from the recipe's own recorded taste scores combined with what each ingredient contributes, weighted by how much of it is in the glass. Almost everything in this drink has detailed ingredient data behind it.

How balance actually works →

If it isn't right

What goes wrong with this drink, and why

Only the faults this particular recipe is actually prone to — each with the likely cause, the adjustment, and what the adjustment costs you.

  • It's too sweet

    Likely cause
    Honey syrup is carrying the sugar here, and it is the easiest thing in the drink to over-pour — syrup clings to a jigger and a "splash" is rarely the same twice.
    What to change
    Cut honey syrup by about a third and rebuild. If it is already made, a squeeze of citrus is faster than starting again.
    What that does
    The drink will read sharper as well as less sweet, because the acid stops being balanced. That is usually the intention, but it is a bigger change than it sounds.

  • It's too sour

    Likely cause
    Fresh lemon juice varies more than any other ingredient in the drink. Limes differ by weeks of ripeness, and a sharp one can be half again as acidic as a mild one at the same measure.
    What to change
    Add sweetener a few millilitres at a time rather than diluting — you are correcting a ratio, not a concentration.
    What that does
    Sourness recedes and the drink gains a little weight. Overshoot and you will be reading the too-sweet entry above instead.

  • It's too strong

    Likely cause
    Blended Scotch whisky dominates by design here — this is a drink built to be sipped, and it is under-diluted more often than it is over-poured.
    What to change
    Shaking for longer, or add a measured 5–10ml of water. Both are the same correction; one is just more honest about it.
    What that does
    Alcohol heat drops and the aromatics open up — a slightly diluted spirit-forward drink usually smells better, not worse.

  • It's watery

    Likely cause
    Shaking adds water while it chills, and the two cannot be separated. Wet ice from a freezer door, or small cubes, will over-dilute before the drink is properly cold.
    What to change
    Use bigger, drier, colder ice and stop sooner. Chilling the glass first buys you time you would otherwise spend diluting.
    What that does
    More flavour concentration at the same temperature. Under-dilute instead and the drink will taste harsh — this is a target, not a direction.

  • It doesn't smell of anything

    Likely cause
    The aroma you are missing is probably citrus peel, which sits above the drink rather than in it — skipping or under-expressing the garnish removes it entirely.
    What to change
    Express the peel over the surface with the skin facing the drink, then drop it in. Herbs go in the glass, not on the side.
    What that does
    Aroma arrives before flavour does, so the whole drink reads as more intense without a single measure changing. The oil does land in the drink, though — an over-expressed peel adds a faint bitterness to the first mouthful.

Taste profile

Sweetness
2/5
Sourness
3/5
Bitterness
1/5
Strength
4/5
Fruitiness
0/5
Freshness
1/5
Creaminess
0/5
Smokiness
4/5

Nutrition & alcohol

Estimate onlyBased on standard pours at typical bottle strengths; brands and homemade syrup strengths vary.
Calories
190 kcal
Sugar
14 g
Carbohydrates
15 g
Alcohol units (UK)
2.7
US standard drinks
1.54
ABV
22.8%
Serving size
120 ml
Show calculation assumptions

Source: Calculated from standard measures

Calorie breakdown: ~151 kcal from alcohol, ~39 kcal from sugar and mixers.

Likely range: 143–238 kcal, reflecting the confidence level above — not a lab-measured figure.

Assumes 50ml blended Scotch at 40% ABV and an 8ml Islay Scotch float at 43% ABV.

These figures are estimates, not laboratory measurements — individual tolerance to alcohol varies. See our responsible drinking guidance.

Variations

  • Extra Smoky Penicillin

    Increase the Islay Scotch float to 12–15ml for a more assertively peaty finish.

What kind of drink this is

The structure behind the recipe

A shaken build: a sour-structured whisky-based drink, served over ice — light and lively in the mouth.

Sour-structured

Something sour and something sweet held in balance over a base — the structure behind the whole sour family and everything descended from it.

  • Base

    Blended Scotch whisky

    Spirit in the largest measure — read as the base.

  • Modifier

    Islay Scotch whisky

    A spirit, but not the largest measure — read as a modifier.

  • Sour element

    Fresh lemon juice

    A short, sharp measure — recorded acidity 5/5, and nothing sharper is poured short, so this is the sour element.

  • Sweet element

    Honey syrup

    A syrup — its whole job in the drink is to sweeten and to add a little body along with it.

    Ginger syrup

    A syrup — its whole job in the drink is to sweeten and to add a little body along with it.

Drinks built this way are collected as the Sour family.

5 components' roles areworked out from the ingredient's category and recorded taste attributes rather than set by hand — the reasoning is shown above so you can disagree with it.

Technique

shaken

Ice is thrown against the liquid and against itself, chipping fragments off and driving air through the mix. Chilling, dilution and aeration all happen at once and cannot be separated.

A lighter, briefly frothy body and a cloudy appearance that settles as it stands. The aeration blunts alcoholic heat, which is why a shaken drink tastes softer than a stirred one of the same strength.

What it ruins: Clarity, and any carbonation. A shaken spirits-only drink arrives cloudy with ice shards floating in it, and shaking anything fizzy is the one rule with no exceptions.

Also involves layering.

Everything about shaking →How the technique works →

Dilution

During mixing, then strained

Water from ice typically makes up around 30% of the finished drink for a shaken build (commonly 25–35%). Dilution is an ingredient here, not a side effect.

Why dilution is an ingredient →

Served

Over ice

Rocks glass · 120ml

Served on ice, so it keeps chilling in the glass. A larger, colder, slower drink than the same spirits served straight up.

Texture and aroma

Light and livelyLemon peel

Shaking whips air through the drink, giving a lighter, briefly frothy body that settles as it stands.

Aroma arrives before flavour does. A citrus twist is expressed over the surface so its oils sit on top of the drink — skipping it changes the drink more than its size suggests.

Where to go from here

Each of these is here because of something specific about this drink, not as a standard set of links.

Where it comes from

Origin and family

Origin of the Penicillin

Modern classic created in 2005 by Sam Ross at Milk & Honey, New York.

Family

Sour

2 parts spirit · 1 part citrus · 1 part sweetener — shaken, strained, served up or over ice.

1980 onwardOther modern classics drinks →

On drinks history

Cocktail origin stories are frequently repeated and rarely evidenced. Our history section separates what is documented from what is folklore rather than picking whichever version reads best.

History and culture →

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Related tools

Scale this for a party

Work out bottles, mixers, ice and total alcohol units for any number of guests.

Recipe confidence

A well-documented modern classic with a widely agreed recipe and technique.

High confidence