How to Tell If an Avocado Has Gone Bad: 7 Signs It’s Spoiled

If you're wondering how to tell if an avocado has gone bad, the answer is more complicated than just looking at the color. Avocados can turn brown due to natural oxidation, become mushy as they overripen, or develop dark streaks from cold storage, all of which can still be safe to eat.

Actual spoilage is far less common but has very specific signs.

This guide explains the science behind avocado browning, the difference between overripe and spoiled avocados, and the 7 checks you can use to determine whether your avocado is still safe to eat.

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What Is Avocado Browning?

Avocado browning is the natural color change that happens when avocado flesh is exposed to air after cutting or bruising. This process is called enzymatic browning and occurs when the enzyme polyphenol oxidase (PPO) reacts with oxygen and natural compounds in the fruit, producing brown pigments. This reaction is chemical, not microbial, which means a brown avocado is not necessarily spoiled — in many cases, it is still safe to eat.

Why Avocados Brown: The PPO Enzyme Mechanism

Understanding why avocados brown — the actual biochemical mechanism — immediately resolves most avocado food safety confusion, because it reveals that browning itself is not a spoilage sign. It is a chemical reaction.

The enzyme responsible: Avocados contain an enzyme called polyphenol oxidase (PPO), stored in the cells of the avocado flesh. Also present in the flesh are phenolic compounds — primarily chlorogenic acid — that serve as the substrate for PPO. Under normal conditions, PPO and its substrate are stored in separate cellular compartments and never come into contact. When avocado cells are damaged — by cutting, bruising, or overripening — these compartments rupture, PPO and chlorogenic acid mix, and in the presence of oxygen, PPO catalyses the oxidation of chlorogenic acid into brown-coloured quinone pigments. These pigments polymerise into the dark brown melanin that turns avocado flesh brown.

What PPO browning is not: PPO-driven enzymatic browning is a purely chemical reaction. It is not caused by bacteria, not caused by mould, and not a sign that the avocado is unsafe to eat. The brown colour indicates that cells have been damaged and that oxidation has occurred — nothing more. Brown avocado flesh tastes slightly more bitter than green flesh (the quinone pigments have a mildly bitter flavour) and has reduced visual appeal, but it is not spoiled and is not unsafe.

Three browning types to distinguish:

Browning Type	Cause	Appearance	Safe to Eat?	Action
Oxidative browning (PPO reaction)	PPO enzyme + phenolic compounds + oxygen after cutting or bruising	Brown or grey-brown discolouration on cut surface or around bruised areas. Green flesh underneath when brown layer is scraped away.	Yes — harmless chemical reaction	Scrape off or cut away brown surface. Green flesh underneath is fine.
Vascular browning (cold-stress)	Exposure to temperatures below 4°C before ripening damages the vascular tissue (the fluid-transport network) running through the fruit	Dark brown or black streaks running lengthwise through the flesh, following the vascular bundle pattern. Surrounding flesh is green and normal.	Yes — cosmetic damage from cold, not spoilage. Some bitterness in the streak tissue itself.	Cut away dark streaks if taste is affected. Surrounding flesh is safe.
Overripe browning	Natural senescence — cell walls break down, sugars ferment slightly, cellular compartments rupture throughout	Uniform brown or brownish-green flesh throughout, or large brown patches. Flesh may be soft to mushy. Smell is still avocado-like.	Yes for most uses — overripe is not spoiled. Texture unsuitable for slicing but fine for mashing.	Use immediately in guacamole, smoothies, dips, or baking. Do not discard if smell is acceptable.
Fungal/bacterial spoilage	Mould or bacterial colonisation of the flesh	Dark grey-black flesh that is slimy, stringy, or has a hollow/fibrous texture. May have visible mould. Smell is putrid, rancid, fermented, or ammonia-like.	No — discard	Discard entire avocado if spoilage smell present or if mould is visible on flesh.
Rancidity	Oxidation of avocado's high fat content (monounsaturated oleic acid ~70%) over time, producing aldehydes and ketones	Flesh may look brown or normal. The tell is the smell — distinctly chemical, soapy, paint-like, or rancid. Different from normal avocado smell or overripe smell.	No — rancid fats are unpleasant and potentially irritating to digestion	Discard if smell is chemical, soapy, or rancid rather than just earthy/mushy.

The Five Avocado Stages: What Each Looks Like and What It's Good For

The most practically useful framework for avocado assessment is understanding the ripeness spectrum. 'Has it gone bad?' is rarely a binary question — most of the time, the real question is 'what stage is this at and what can I use it for?'

Stage	Skin (Hass)	Flesh	Squeeze Test	Smell	Best For	Action
1. Underripe	Bright green, firm, smooth	Pale green, very firm — will not mash	Rock hard — no give whatsoever	Almost no aroma	Nothing yet — needs to ripen	Leave at room temperature 2–5 days. Speed up with paper bag + banana (ethylene).
2. Nearly ripe	Green to dark green	Firm green flesh with some give	Firm but slight give at widest point. Like a firm plum.	Faint nutty, grassy aroma	Slicing for salads if softer ripening wanted; otherwise wait 1 day	Leave at room temperature 1 day or refrigerate to hold.
3. Perfectly ripe	Dark green to nearly black (Hass)	Bright green to yellow-green, creamy and smooth	Gives slightly under gentle palm pressure — springs back. Does NOT leave permanent indentation.	Mild, nutty, buttery aroma	Everything: toast, slicing, guacamole, salads, sushi	Use today. Refrigerate to hold for 1–2 more days.
4. Overripe (still usable)	Nearly black, possibly with sunken spots	Brownish-green to brown throughout. Soft to mushy. May have some stringy patches. Smells like avocado.	Soft, leaves some indentation. Does not spring back.	Stronger, earthier avocado smell. Not unpleasant — just more intense.	Guacamole (colour doesn't matter when mashed), smoothies, avocado toast (will be mushy spread), baking (avocado brownies, muffins, banana bread addition), face/hair masks	Use today. Do not refrigerate further.
5. Spoiled	Black, sunken, leathery or collapsing	Grey-black, slimy, stringy, fibrous, hollow, or uniformly dark with off smell	Collapses under pressure. Possible hollow feeling from pit separation.	Rancid (chemical/soapy), putrid (ammonia/rotten), or strongly fermented. Clearly unpleasant.	Nothing — discard	Discard. Compost if no mould; bin if mould present.

Variety-Specific Colour Rules: Why Hass and Non-Hass Avocados Are Different

The colour-based ripeness assessment that most guides describe — dark green to nearly black = ripe, bright green = unripe — applies specifically to Hass avocados, which account for approximately 90% of the avocados sold in Canadian supermarkets. It does not apply to other varieties.

Variety	Skin When Unripe	Skin When Ripe	Skin When Overripe	Colour Reliable Ripeness Indicator?	Notes
Hass (most common in Canada)	Bright, bumpy, vivid green	Dark green to nearly black; bumpy	Nearly black, possibly leathery or collapsing	✅ Yes — colour is a reliable indicator for Hass	The standard variety at Loblaws, Metro, Sobeys, Costco, and virtually every Canadian supermarket. Over 90% of Canadian avocado sales.
Fuerte	Smooth, medium green	Medium green — does NOT darken significantly	Slightly more olive or muted green; may develop soft spots	❌ No — stays green regardless of ripeness	Pear-shaped. Less common in Canada but appears at specialty stores and some large Loblaws.
Bacon	Thin, smooth, light green	Light green to slightly yellow-green; stays fairly light	Light green, very soft	❌ No — colour change minimal	Available occasionally at specialty stores. Milder flavour than Hass.
Zutano	Shiny, thin, light green to yellow-green	Light green — does NOT darken significantly	Yellow-green to slightly brownish; very soft	❌ No — colour is not a reliable indicator	Uncommon in Canadian retail; occasionally at specialty grocers.
Reed (round)	Round, dark green, smooth	Dark green — does not change dramatically	Dark green but very soft	⚠️ Partially — squeeze is more reliable than colour	Appears occasionally at specialty produce stores.

The Complete Spoilage Assessment: 7 Checks in Order

Run through these checks in sequence — each one builds on the previous and takes 10–15 seconds total.

Check	What to Do	✅ Normal / Usable	❌ Spoilage Sign
1. Exterior mould	Look at the entire skin surface, especially around the stem and any soft spots or cracks	No mould — skin may be dark or slightly leathery but clean	Any fuzzy growth (white, grey, green, black) on the skin. Discard immediately.
2. Squeeze test	Gently squeeze the avocado in your palm (not your fingertips — fingertip pressure bruises)	Slight give that springs back = ripe. Mushy soft with permanent indentation = overripe. Both are usable.	Collapses almost completely, feels hollow or sloshy, or makes a rattling sound when shaken (pit has separated from flesh) = likely spoiled inside.
3. Stem trick	Flick off the small dry nub at the stem end with your thumb. Look at the colour underneath.	Green or pale yellow underneath = ripe. Slightly tan-brown = overripe but usable.	Dark brown, black, or mushy underneath. Indicates the flesh directly below, and likely much of the fruit, is overripe or spoiled.
4. Smell (whole)	Smell the stem end, which releases the most aroma	Faint nutty, earthy, or buttery smell = ripe. Stronger earthy avocado smell = overripe.	Chemical, soapy, paint-like = rancid. Fermented, vinegary, or putrid = bacterial spoilage. Both = discard.
5. Cut and assess flesh colour	Slice open. Note the overall flesh colour.	Bright green or yellow-green = ripe. Brownish-green or uniform light brown = overripe. Isolated brown spots or streaks = oxidative browning or vascular browning.	Grey-black uniform flesh. Large black patches with soft, slimy, or stringy texture. These are spoilage, not browning.
6. Check texture of flesh	Touch the flesh gently	Creamy, smooth = ripe. Soft or slightly stringy but intact = overripe. Slight stringiness is normal in very ripe avocado.	Slimy (wet, slippery surface), fibrous to the point of inedible, or hollow/air-pocket texture = spoilage. Discard.
7. Smell (cut)	Smell the flesh after cutting	Avocado smell — mild to strong earthy, nutty, slightly grassy	Rancid/chemical/soapy OR putrid/ammonia/rotten. If smell is clearly unpleasant and nothing like avocado, discard.

The Stem Trick: Explained Properly

The stem trick — removing the small dry nub at the stem end and checking the colour underneath — is genuinely useful, but the explanation of why it works is almost always wrong or absent in guides that mention it.

Why it works: The small brown button at the stem end is a dried remnant of the stem that attached the avocado to the tree. It is not the stem itself but the callus that forms after separation. Underneath this button is the flesh at the very top of the fruit — essentially a tiny window into the interior. Because this is the thinnest part of the avocado's skin structure, the flesh here ripens and ages at roughly the same rate as the flesh in the middle. Its colour provides a genuine — if limited — preview of the interior.

What you see and what it means:

•       Green or pale yellow-green: The avocado is at or approaching peak ripeness. The interior flesh is likely at its best.

•       Tan or light brown: The avocado is ripe to overripe. The flesh may have started to brown at the core. Still usable — use today.

•       Dark brown, black, or mushy: The flesh at the top is already significantly deteriorated. The interior is likely overripe to spoiled. Proceed with the cut assessment before committing, but manage expectations.

The stem trick's limitations: It is a preview of the top of the fruit, not the entire interior. An avocado with a brown stem base can still have good flesh in the lower half — and vice versa, a green stem base does not guarantee the interior is undamaged (bruising from transport affects the interior independent of stem-end condition). Use the stem trick as a first filter at the grocery store or kitchen counter, not as a definitive verdict.

Rancidity vs Bacterial Spoilage: Two Different Spoilage Pathways

Most avocado guides mention that a bad smell means spoilage, but they rarely specify what type of bad smell indicates what type of spoilage. There are two distinct spoilage pathways in avocados, and they produce meaningfully different smells:

Rancidity — fat oxidation: Avocados are approximately 15–20% fat by weight, with roughly 70% of that fat being monounsaturated oleic acid — the same fatty acid that makes olive oil healthy and shelf-stable. However, even monounsaturated fats eventually oxidise over time, particularly when the protective cell structure breaks down in a very overripe or damaged avocado. This fat oxidation (rancidity) produces volatile compounds including hexanal, nonanal, and other aldehydes and ketones. The smell is characteristically chemical, soapy, paint-like, or reminiscent of old cooking oil — a sharp, somewhat artificial smell very unlike the mild earthy aroma of fresh avocado.

Bacterial spoilage — protein decomposition: When bacteria colonise the flesh (usually entering through damaged skin or the stem end), they break down the proteins in the fruit, producing volatile amine compounds — putrescine, cadaverine, trimethylamine. These produce the rotten, ammonia-like, or strongly fermented smell associated with spoiled food generally. This is qualitatively distinct from the chemical-rancid smell of fat oxidation.

Spoilage Type	Smell	Visual Signs	Cause	Safe to Eat?
Rancidity (fat oxidation)	Chemical, soapy, paint-like, or old-oil smell. Sharp and somewhat artificial. Clearly different from normal avocado smell.	May look brown or normal — colour is not the tell for rancidity	Long-term oxygen exposure to high-fat flesh; more common in very overripe avocados or those stored for extended periods after cutting	No — rancid fats are unpleasant and can cause digestive irritation
Bacterial spoilage	Putrid, ammonia-like, rotten, or strongly fermented (wine/vinegar-like) smell. Unmistakeable rotten-food quality.	Grey-black flesh, slimy or stringy texture, possible mould on skin or flesh	Bacterial colonisation through damaged skin, stem end, or cross-contamination	No — discard immediately
Overripe (not spoilage)	Earthy, nutty, stronger than fresh avocado but still avocado-like. Not chemical, not rotten.	Brown flesh, mushy texture, but no sliminess, no hollow feel, no mould	Natural senescence — cell breakdown, PPO browning throughout	Yes — use for guacamole, smoothies, baking

How Long Does Avocado Last? Shelf Life by Stage and Storage Method

Avocado State	Room Temperature	Refrigerator	Freezer	Notes
Whole, unripe	3–7 days until ripe	Do NOT refrigerate — stops ripening; may cause vascular browning (dark streaks)	Not recommended	Leave on counter. Speed ripening with paper bag + ripe banana or apple (ethylene gas). Check daily from day 3.
Whole, ripe	1–2 days maximum before overripe	3–5 days	Not ideal — texture changes	Once ripe, refrigerate immediately if not using today. Slows but does not stop ripening.
Whole, overripe	Use immediately	1–2 days	Not recommended	Use today. Making guacamole today = the best use.
Halved, with pit, cut side wrapped in cling wrap	2–4 hours only — browning begins quickly	1–2 days (flesh will brown on surface — scrape away before using)	N/A	Press cling wrap directly against flesh surface to minimise air contact. Pit only prevents browning in the area it directly covers — not the whole half.
Halved, with lemon or lime juice on cut surface	2–4 hours	2–3 days	N/A	The acid (citric acid, ascorbic acid) lowers pH, which slows PPO enzyme activity. Most effective browning prevention method for cut avocado.
Mashed/guacamole	2–4 hours (browning accelerates when mashed)	2–3 days in airtight container with cling wrap pressed to surface	Not recommended	Lime juice in guacamole slows browning. Press cling wrap directly onto guacamole surface before sealing container — this is more effective than just putting a lid on.
Diced/sliced	1–2 hours	1–2 days tossed in lime juice in sealed container	Not ideal	Most surface area exposed = fastest browning and texture degradation.
Frozen (mashed, with lemon juice)	N/A	N/A	3–6 months	Mash thoroughly, add 1 tbsp lemon juice per avocado, freeze in airtight container or zip-lock bag. Texture on thawing is soft and suitable only for guacamole or blended uses — not slicing. Defrost in fridge overnight.

The Pit Storage Myth: What It Actually Does (and Doesn't Do)

One of the most widely repeated avocado storage tips is to leave the pit in the cut half to prevent browning. This is partially true in a very limited way, and mostly misleading.

What the pit actually does: The pit prevents browning only in the small area of flesh that is physically covered by or in direct contact with the pit. The flesh around the pit that is not directly underneath it browns normally through PPO oxidation. The mechanism is simply physical exclusion of oxygen — the pit covers a patch of flesh so air cannot reach it. It has no chemical, hormonal, or enzymatic effect on the rest of the avocado.

What actually prevents browning: Acid (lemon juice, lime juice, vitamin C/ascorbic acid) applied to the cut surface is significantly more effective than the pit. Acid works by two mechanisms: (1) lowering the pH of the flesh surface below the optimal range for PPO enzyme activity (~6.0–7.0), reducing how quickly the enzyme catalyses browning; and (2) ascorbic acid (vitamin C in citrus) acts as a preferential substrate for PPO — the enzyme reacts with ascorbic acid first rather than with chlorogenic acid, buying time before browning begins. Additionally, plastic cling wrap pressed directly against the cut surface excludes air mechanically — far more effective than the pit at covering the full cut surface.

What to Do With Overripe Avocados: Don't Throw Them Away

An avocado that is brown, mushy, and past its slicing peak is not waste — it is an ingredient. These are the best uses for overripe avocados:

•       Guacamole: The most natural use. Overripe avocados mash easily, colour does not matter once mashed and mixed with lime juice, tomato, and cilantro, and the more intense flavour of a very ripe avocado often produces better guacamole than an under-ripe one. The lime juice in guacamole also slows further browning.

•       Smoothies: Avocado adds creaminess, fat, and nutrients to smoothies. An overripe brown avocado in a blended smoothie with banana, spinach, and almond milk is indistinguishable from a perfectly ripe one — the colour disappears and the texture is fully homogenised.

•       Avocado toast (mashed spread): An overripe avocado makes a better mashed toast topping than a barely-ripe one. Mash with lemon juice, salt, and pepper — the colour will be brownish-green but the taste is good and the texture is spreadable.

•       Baking: Mashed overripe avocado can substitute for butter or oil in some baking recipes — avocado brownies, chocolate avocado muffins, and avocado banana bread use the fat and moisture content of the avocado directly. Overripe avocados with higher fat content and softer texture actually work better than firm ones in these applications.

•       Avocado pasta sauce: Blended with garlic, lemon juice, olive oil, and pasta water, overripe avocado becomes a creamy pasta sauce. The heat of hot pasta mellows the slightly bitter notes of browning. A very simple weeknight meal that uses avocados that would otherwise be wasted.

•       Face or hair mask: Avocado's fat and vitamin content makes overripe avocado (too far gone for eating) genuinely useful as a moisturising skin or hair mask. Mash with honey for a face mask; mash with coconut oil for a hair mask. This extends the useful life of avocados beyond the kitchen entirely.

For Food Businesses in Canada: Avocado in Commercial Kitchens

Mexican restaurants, guacamole catering operations, avocado toast cafés, and sushi restaurants in Canada all use avocado in high volumes and face specific food safety and waste management challenges:

• Bulk ripening management: For commercial operations buying cases of avocados, ripeness management is critical. Buy a mix of ripeness stages — some underripe (for use later in the week), some ripe (for today's service). Avoid buying all ripe avocados in bulk as they will all overripen simultaneously. Store underripe avocados at room temperature; move to refrigeration once ripe.
• Pre-cut avocado holding: Cut avocados for service should be treated with lemon or lime juice immediately after cutting and refrigerated at 4°C. For buffet or cold display service, cut avocado held at room temperature should be replaced every 2 hours (same 2-hour room temperature rule as other fresh-cut produce under CFIA guidelines).
• Guacamole storage and freshness: Fresh guacamole oxidises faster than whole cut avocado because the surface area is vastly increased through mashing. Commercial guacamole should have cling wrap pressed directly to the surface before refrigerating, and should be made in batches sized for same-day use rather than prepared in large quantities that will hold for multiple days.
• Packaging for guacamole portions: Individual sealed guacamole portion cups (with tight-fitting lids) for table service or takeout maintain freshness better than open ramekins. Press a small round of cling wrap directly against the guacamole surface inside the cup before sealing the lid for maximum browning prevention during delivery.

KimEcopak supplies portion cups for guacamole and avocado-based dips, kraft takeout containers, and eco-friendly Mexican and Latin American restaurant packaging wholesale across Canada. Free samples available.

Frequently Asked Questions: How to Tell If an Avocado Has Gone Bad

Usually yes, depending on what caused the browning. Brown discolouration from oxidation (PPO enzyme reaction after cutting or bruising) is harmless — the flesh may taste slightly more bitter than green flesh, but it is safe to eat. Scrape away the brown surface layer if the taste or colour bothers you; the flesh underneath is fine. Brown flesh throughout an overripe avocado is also not a safety concern — the avocado is past its peak for slicing but is excellent for guacamole, smoothies, or baking. The browning that indicates spoilage is brown-to-grey flesh that is also slimy, stringy, or hollow in texture, accompanied by a rancid or putrid smell. The smell is the most reliable indicator — if the brown flesh smells like avocado (even a strong avocado), it is fine. If it smells chemical, soapy, or rotten, discard it.

Dark brown or black streaks running lengthwise through otherwise normal-looking avocado flesh are called vascular browning. They form in the vascular tissue (the fluid-transport network) that runs through the fruit when the avocado was exposed to cold temperatures (below 4°C) before it had fully ripened. Supermarkets and distribution centres sometimes hold avocados too cold, causing this cold-stress damage. Vascular browning is not spoilage — it is cosmetic damage. The flesh surrounding the dark streaks is safe to eat. The streaks themselves may taste slightly more bitter. Cut around them if the taste bothers you, or blend the avocado (for guacamole or smoothies) where the streaks become invisible.

Not necessarily, if the avocado is a Hass variety (the most common in Canada). Hass avocados turn from bright green to dark green to nearly black as they ripen — a nearly black Hass avocado in good condition is likely overripe or very ripe, not spoiled. The key additional check is texture: a dark Hass avocado that has slight give but does not collapse or feel hollow is likely fine for guacamole or immediate use. A dark avocado that collapses completely, has deep sunken pockets, or feels hollow and rattles is likely spoiled. Cut it open to confirm — if the flesh is uniformly grey-black with a rotten or rancid smell, discard it. If the flesh is brown but smells like avocado, it is overripe and usable.

A cut avocado half with lime or lemon juice applied to the cut surface and cling wrap pressed directly against the flesh will last approximately 2–3 days in the fridge before significant browning and texture deterioration. Without acid and with just a lid on the container, 1–2 days at most before the surface browns significantly. Diced avocado tossed in lime juice in a sealed container lasts about 1–2 days. Mashed avocado or guacamole with lime juice, cling wrap pressed to the surface, and a sealed container lid lasts 2–3 days. In all cases, a small amount of surface browning is normal — scrape away the brown layer to reveal the green flesh underneath.

It depends on the type of sourness. A very slightly sour or fermented note in an overripe avocado's smell — mixed with the normal earthy avocado aroma — can be within the range of normal for a very ripe fruit where some sugars have begun to ferment. If the overall smell is 'strong avocado with a slight edge,' the avocado is likely overripe but not spoiled. If the smell is strongly sour, vinegary, or clearly fermented — where the avocado aroma is secondary to the sour smell — the avocado is likely spoiled. A chemical or soapy smell is rancidity. A rotten, ammonia, or sulphurous smell is bacterial spoilage. All three of the 'stronger' scenarios (strongly fermented, chemical-rancid, putrid) mean discard.

The speed of browning depends on several factors: (1) How ripe the avocado is — very ripe avocados brown faster because more cells have broken down, releasing more PPO enzyme in contact with phenolic compounds. (2) How much surface area is exposed — diced avocado browns much faster than a halved avocado because the ratio of surface to volume is much higher. (3) Temperature — at room temperature, PPO is more active than at refrigerator temperature. (4) Whether acid was applied — lime or lemon juice significantly slows PPO activity. The most effective combination: refrigerate immediately after cutting, apply lime juice to all cut surfaces, and press cling wrap directly against the flesh before closing the container.

No. Visible mould on avocado skin should be treated as a discard indicator. Unlike hard vegetables where mould on the outer skin does not necessarily penetrate deeply, avocado skin is thin and any mould on the exterior has almost certainly penetrated into the flesh underneath and around the affected area. Additionally, mould around the stem end or in skin cracks can travel along the fruit's vascular tissue into the interior. Discard any avocado with visible mould on the skin without cutting around it.

Conclusion: The Three Checks That Take 30 Seconds

The most common assessment failure with avocados is conflating browning with spoilage. Brown flesh is almost always enzymatic browning (PPO reaction) or overripeness — neither is a food safety concern. The genuine spoilage indicators are the smell (rancid-chemical or putrid-rotten, clearly different from 'strong avocado'), the texture (slimy, stringy, hollow), and visible mould.

The 30-second assessment: squeeze (does it feel hollow or completely collapse?), smell the stem end (does it smell like avocado, even a strong one?), look at the flesh when cut (grey-black-slimy or brown-mushy?). If the answers are no / yes / brown-mushy, you have an overripe avocado — make guacamole. If the answers are yes / chemical-rancid or putrid / grey-slimy, you have a spoiled avocado — discard it.