Hidden Peanut Ingredients
in Thai Street Food

Peanuts appear in four different forms in Thai cooking

Understanding the forms makes it easier to know what to ask about. Requesting "no peanuts" addresses the garnish — but it doesn't address the oil, the paste, or the sauce. This guide is a reference for that distinction. For broader travel preparation and dish-level risk, see Traveling Thailand with a Peanut Allergy. For how to assess individual stalls and make decisions in real time, see the street food guide.

1. Peanut oil in the wok

This is the least visible and most structurally difficult to avoid. Peanut oil is a standard cooking fat at many Thai street stalls and wok-based restaurants. It has a high smoke point, a neutral-to-slightly-nutty flavor, and it's cheap and widely available in Thailand. Vendors don't advertise it. It won't appear on any menu. And at a busy stall with a single large oil container, swapping oils for one order is often genuinely impractical.

The allergy relevance depends on the oil type. Highly refined peanut oil has most peanut protein removed and is considered lower risk by some allergists. Cold-pressed or crude peanut oil retains protein and can cause reactions. At a street stall, you won't know which you're getting. If your allergy is anaphylactic, this uncertainty matters.

Thai to show: ไม่ใส่น้ำมันถั่วลิสง · mai sai nam man thua lisong (no peanut oil)

2. Crushed peanuts as a garnish

This is the most visible form — and the one most travelers focus on. Crushed or coarsely ground peanuts are scattered on top of a finished dish as a standard presentation. The problem is that "no peanuts on top" is the easy request. It doesn't address the oil, the paste, or shared equipment. Vendors often hear "no peanuts" and remove the garnish while the dish is otherwise unchanged.

Dishes where this is standard: pad thai (almost always), some versions of khao soi, certain noodle soups, and some curry dishes in northern Thailand.

Thai to show: ไม่ใส่ถั่วลิสง · mai sai thua lisong (no peanuts)

3. Ground into curry paste or sauce

Some Thai dishes incorporate peanuts not as a garnish but as a structural ingredient ground into the base. Massaman curry is the most significant example — traditional massaman paste or the curry itself often contains peanuts mixed in during cooking, making them impossible to remove from a finished dish.

Satay sauce is peanut-based by definition. It's a thick, rich sauce made from ground peanuts, coconut milk, and spices. It appears as the dipping sauce for satay skewers but is sometimes also used as a sauce for noodle dishes.

Thai to show: แพ้ถั่วลิสงอย่างรุนแรง · pae thua lisong yang run raeng (severely allergic to peanuts)

4. Whole or crushed peanuts mixed directly into the dish

Som tam (green papaya salad) is the main example. Peanuts are a standard ingredient that gets pounded directly into the salad in the mortar — not added on top after. They're mixed through the dish during preparation, meaning they can't be removed once the dish is made. The additional complication: the same mortar is used for multiple orders at a busy stall, so even a som tam prepared without peanuts may have peanut residue from the previous order.

Some versions of pad see ew and certain noodle dishes also incorporate peanuts this way in specific regional preparations.

Dish-by-dish peanut risk breakdown

The cross-contamination problem at street stalls

Even if a specific dish contains no peanuts as an ingredient, the cooking environment at a busy street stall introduces cross-contamination risk. One wok handles multiple dishes in rapid succession. The same spatula moves between orders. Peanuts spilled during a previous order remain on the cooking surface.

This doesn't mean all street food is off-limits for travelers with peanut allergies. It means the stall matters as much as the dish. A stall that specializes in one or two simple dishes — grilled meat, mango sticky rice, fresh fruit — has a completely different risk profile than a multi-dish wok stall running pad thai alongside everything else.

For travelers with anaphylactic peanut allergies, the cross-contamination reality of busy multi-dish stalls is a genuine constraint. Being honest with yourself about this is more useful than trying to negotiate it dish by dish.

What to show vendors

Verbal requests in English get misheard, misunderstood, or interpreted as a preference rather than a medical need. Written Thai is more reliable. Specificity matters — "no peanuts" addresses the garnish; a card that states the allergy is severe and covers peanut oil gets taken more seriously.

The phrases that matter most:

• แพ้ถั่วลิสงอย่างรุนแรง — severely allergic to peanuts
• ไม่ใส่ถั่วลิสง — no peanuts
• ไม่ใส่น้ำมันถั่วลิสง — no peanut oil
• ไม่ใส่ซอสถั่ว — no peanut sauce

AllergyPass generates a free Thai-English allergy card that includes all of these, formatted to show at restaurants and street stalls. It also covers other allergens if your needs go beyond peanuts.

Frequently asked questions

Does Thai street food use peanut oil?

Yes, commonly. Peanut oil is a standard cooking fat at many Thai street stalls. It won't be listed on any menu or announced by vendors. At a busy stall using a single large oil container, changing oil for one order is usually not realistic. If your allergy extends to peanut oil (not just whole peanuts), this is a significant factor in assessing stall-by-stall risk.

What Thai dishes contain hidden peanuts?

The main sources of hidden peanuts are: pad thai (peanut garnish, often peanut oil), massaman curry (peanuts cooked into the dish), som tam (peanuts pounded in during preparation), satay sauce (peanut-based), and fresh spring rolls (peanut dipping sauce). Cross-contamination from shared woks affects almost any stall-cooked dish at busy carts.

Can I ask a Thai vendor to cook without peanut oil?

You can ask, and some will accommodate you. Many stalls use a single oil container for all dishes, making it practically impossible to change. A written Thai-language request is clearer than a spoken one. But the structural reality is that cross-contamination from shared equipment is difficult to fully control at busy multi-dish stalls — regardless of what the vendor confirms.

Is massaman curry safe for peanut allergies?

No — massaman curry is one of the highest-risk Thai dishes for peanut allergy. Traditional recipes incorporate peanuts as a core ingredient, cooked directly into the curry. It's not a garnish that can be removed on request. Even mass-produced restaurant versions typically contain peanuts. Avoid this dish if you have a peanut allergy.

Does som tam (papaya salad) contain peanuts?

Standard som tam does contain peanuts — they're pounded directly into the salad during preparation and can't be removed from a finished dish. Even if you request it without peanuts, the mortar used to prepare it will likely have peanut residue from previous orders. Som tam is a high-risk dish for peanut allergy travelers at busy street stalls.