One green potato typically carries about 8–32 mg of solanine, varying with size and greening; toss any that taste bitter or show broad greening.
Greening on a potato signals light exposure and a likely rise in glycoalkaloids—the natural toxins α-solanine and α-chaconine. The green color itself comes from chlorophyll, but it often accompanies higher toxin levels near the skin and eyes. Labs and regulators talk in “mg per kg of potato” (mg/kg). To answer the everyday question—how much solanine sits in one green potato—we can translate those mg/kg figures into a practical per-potato range using typical potato weights.
What Counts As “Green” And Why Levels Vary
Potato toxin levels swing with variety, storage, light, bruising, and sprouting. Extension data show non-green tubers around 12–20 mg/kg total glycoalkaloids (TGA), while green tubers can reach roughly 250–280 mg/kg; the peel of a green tuber can land far higher (about 1,500–2,200 mg/kg). Those figures refer to the sum of α-solanine and α-chaconine, which together make up nearly all glycoalkaloids in a potato. Peeling trims exposure because much of the load sits in the outer layer and the eyes. (Source: Oregon State University Extension bulletin EM 9407.)
Solanine Versus “Total Glycoalkaloids”
Most food safety references list TGA (α-solanine + α-chaconine). In many samples, α-chaconine runs a bit higher than α-solanine, often near a 60:40 split; some cases flip that balance. Using 40% as a working share for α-solanine gives a realistic per-potato estimate from a quoted TGA number.
Green Potato Numbers At A Glance
The table below summarizes typical ranges reported in the literature and how they translate into solanine exposure. Values describe raw potatoes unless noted.
| Condition | Typical TGA (mg/kg) | Solanine Share (≈40%) |
|---|---|---|
| Well-stored, not green | 12–20 | ~5–8 mg/kg |
| Market average (varied lots) | ~50 | ~20 mg/kg |
| High but still acceptable | ~100 | ~40 mg/kg |
| “Guideline upper” for safety | ~200 | ~80 mg/kg |
| Green tuber (common range) | 250–280 | ~100–112 mg/kg |
| Peel of a green tuber | 1,500–2,200 | ~600–880 mg/kg |
| Damaged or sprouted | Rises with light and injury | Share varies with site |
Why those rows matter: agencies and expert panels evaluate risk using TGA. A widely used “keep it safe” concept is to keep raw tubers near or below 100 mg/kg TGA, with 200 mg/kg a practical ceiling for consumer safety. The EFSA 2020 opinion on potato glycoalkaloids discusses adverse-effect levels and the use of total α-solanine + α-chaconine as the metric. The WHO/JECFA database entry notes that 20–100 mg/kg in properly grown and handled tubers is not a concern.
How Much Solanine Is In One Green Potato? Safety Thresholds
Now let’s turn mg/kg into a real-world estimate per potato. Start with a typical green-tuber TGA near 200 mg/kg. Assume α-solanine is about 40% of that TGA. Multiply by the weight of the potato in kilograms.
Quick Method To Estimate Your Potato
- Weigh the potato (or pick a size class below).
- Pick a TGA line that fits what you see. Pale patches near the skin? Use 200 mg/kg. Deep, wide greening? Use 250–280 mg/kg.
- Take 40% of that number to estimate α-solanine.
- Multiply by potato weight (kg). That yields mg solanine in that potato.
Worked Examples
- 200 g green potato at 200 mg/kg TGA → 40 mg TGA × 0.4 ≈ 16 mg solanine.
- 300 g green potato at 200 mg/kg TGA → 60 mg TGA × 0.4 ≈ 24 mg solanine.
- 250 g greener potato at 280 mg/kg TGA → 70 mg TGA × 0.4 ≈ 28 mg solanine.
When The Peel Drives Intake
Peel can carry a large share of the load. EM 9407 reports green-tuber peel at roughly 1,500–2,200 mg/kg TGA. A 200 g potato with peel intact will deliver more glycoalkaloids than the same weight peeled, because the outer 2–3% of the tuber holds a concentrated layer.
Taking Action In The Kitchen
Food safety panels set guidance figures using symptoms seen in outbreaks, volunteer data, and case reports. The EFSA Panel lists a lowest observed adverse-effect level near 1 mg TGA per kg body weight per day. For a 70-kg adult, that’s about 70 mg TGA in a day; for a 20-kg child, about 20 mg TGA. Those figures reflect total α-solanine + α-chaconine, not solanine alone.
Practical Rules You Can Use
- Skip potatoes with broad greening, many sprouts, or a bitter bite.
- Peel and trim deeply around eyes and green patches. This removes much of the glycoalkaloid load that sits near the skin.
- Cook as you like, but do not count on heat to “clear” toxins. Glycoalkaloids resist normal boiling and baking; only very hot frying can cut levels meaningfully. EM 9407 notes a ~40% reduction at 210°C frying, with little change at lower temperatures.
- Store in a cool, dark, well-ventilated spot. Light and bruising raise glycoalkaloids during storage.
What About Taste As A Warning Sign?
Bitterness can hint at high glycoalkaloids. That said, taste is not a lab test, and people vary in perception. If a baked or boiled potato tastes off, do not finish it.
Can I Eat Small Green Areas If I Trim Them?
Trimming removes much of the toxin-rich tissue. The risk depends on how deep the greening goes and how much you keep. If the patch is narrow and you carve it away with a wide margin, you cut exposure. If greening covers a large fraction of the potato or the flesh under the skin looks green, discard it. Public health pages advise tossing green or sprouted potatoes to avoid toxin risk.
Close Variant: How Much Solanine In A Green Potato? Estimating By Weight
The table below converts a single working assumption—200 mg/kg TGA with α-solanine near 40%—into per-potato amounts for common weights. This gives a fast sense of scale for one green tuber on your cutting board.
| Potato Weight | Assumed TGA → Solanine | Estimated Solanine In One Green Potato |
|---|---|---|
| 100 g (small) | 200 mg/kg → 40% | ~8 mg |
| 150 g (small-medium) | 200 mg/kg → 40% | ~12 mg |
| 200 g (medium) | 200 mg/kg → 40% | ~16 mg |
| 250 g (medium-large) | 200 mg/kg → 40% | ~20 mg |
| 300 g (large) | 200 mg/kg → 40% | ~24 mg |
| 350 g (large) | 200 mg/kg → 40% | ~28 mg |
| 400 g (very large) | 200 mg/kg → 40% | ~32 mg |
Where The Numbers Come From
Three sources anchor the figures used here. First, the OSU Extension EM 9407 bulletin lists typical ranges for non-green tubers, green tubers, and peel, and summarizes cooking effects. Next, the EFSA scientific opinion (2020) reviews volunteer data and case evidence, placing gastrointestinal effects near 1 mg TGA/kg body weight per day and warning that mixtures of α-solanine and α-chaconine drive toxicity. Finally, the WHO/JECFA database notes that properly grown and handled tubers with 20–100 mg/kg TGA are not a concern.
Simple Checklist For Safe Potato Prep
Before You Buy
- Pick bags with minimal bruising and no visible greening.
- Avoid lots with many sprouts or soft, rubbery tubers.
At Home Storage
- Store in a dark spot at cool room temperature—never in the sun.
- Keep air flowing around the bag or bin; avoid sealed plastic.
- Use older potatoes first and trim cooking plans if you spot greening.
Prep And Cooking
- Peel if you see any green. Carve out eyes and neighboring flesh.
- Discard potatoes with broad green patches or strong bitterness.
- Heat does not “erase” glycoalkaloids; fry hot only if you plan to fry at all.
Answering The Keyword Plainly
How much solanine is in one green potato? Using common TGA ranges for green tubers and a 40% split for α-solanine, a single green potato lands near 8–32 mg of α-solanine for typical home-kitchen sizes. A much greener or larger potato can push that higher, while peeling and deep trimming brings it down.
Key Takeaways You Can Act On Today
- Use color and taste as a screen, not a lab test; when in doubt, toss.
- Peel and trim away eyes and any green flesh to cut toxin exposure.
- Rely on cool, dark storage to prevent greening and sprouting.
- Children are more sensitive on a per-kg basis—serve peeled potatoes from sound stock.