Many of us think seasoning food is trivial — sprinkle a little salt, pepper, MSG, or fish sauce, and our dish is done. But according to Tạp Chí Đời Sống, doing it at the wrong moment or in the wrong way can not only ruin flavor but even produce harmful compounds. tapchinuocmy.com

Below is a refined, deeper version—explaining what the article claims, what science supports (or disputes), and safer practices.

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What the Article Claims

1. Pepper Should Be Added Only After Cooking

The article warns that if you put black pepper into food before cooking, high heat may convert compounds in pepper into carcinogens. Therefore, it recommends sprinkling pepper only after the food is fully cooked. tapchinuocmy.com

2. Salt, When Misused, Can Become Dangerous

• It states that typical seasonings like salt, sugar, MSG, seasoning powders are foundational to Vietnamese cuisine—but using them improperly (wrong timing or quantity) can turn them harmful. tapchinuocmy.com

• The article suggests that when oil exceeds 180 °C, salt may react and produce nitrosamines, harmful compounds linked to cancer risk. Also, iodine in iodized salt may evaporate at high heat, reducing its nutritional value. tapchinuocmy.com

• It adds that coarse salt can scratch iron pans (damaging protective layers) and in nonstick pans high temperature plus abrasive salt might damage the coating. tapchinuocmy.com

3. Seasoning Recommendations for Different Food Types

• Salt: The article says depending on the dish, you may season early or later (e.g. in stews, wait for flavor from bones first, then adjust salt). For stir-fry, it suggests adding salt into the heated oil briefly before adding the main ingredients, which (the article claims) helps eliminate ~95% of aflatoxin contamination. tapchinuocmy.com

• Fish sauce: Because of its delicate aroma and proteins, fish sauce should not be boiled for long. Add it near the end (especially in soups) to preserve flavor and prevent protein breakdown. tapchinuocmy.com

• Sugar: Because sugar can burn, it’s best used sparingly. For sweeter flavor, the article suggests using it later or in separate sauce layers rather than early in the cooking. tapchinuocmy.com

• MSG / Seasoning powder: Best added after cooking rather than early. Over-use early may induce bitterness or negative reactions. tapchinuocmy.com

• Vinegar / acid: Useful for de-fatting, softening cellulose in vegetables, and balancing flavors. The article suggests adding some vinegar early and more near the end or at serving, depending on recipe type. tapchinuocmy.com

4. Timing by Food Type

• Leafy greens: Season ~30 seconds before finishing to retain crispness, color, and vitamins. Some exceptions like spinach or amaranth (rau dền) may benefit from a small bit of salt during blanching to reduce bitterness. tapchinuocmy.com

• Vegetables / root veggies: For stir-fried veggies, wait until partial browning (3–5 min) before salting, then give a final toss. tapchinuocmy.com

• Meat / poultry / fish: Season twice—once in the marinade (modest amount) and once near the final stage (80–90% cooked) to adjust taste without drawing moisture out prematurely. In stews, delay salt until after ~15–20 minutes. tapchinuocmy.com

• Bean / tofu: After a brief sear to set surface, then salt so it absorbs but doesn’t dry or get rubbery. tapchinuocmy.com

• Soups / stocks: Season twice—once when the broth begins, and again just before removing from heat to fine-tune flavor. Some soups (egg soup, tomato soup) require salt near the end so they don’t curdle or separate. tapchinuocmy.com

They also cite WHO guidance: adults should consume at most 5 g of salt per day (about one teaspoon), and must count hidden salts from soy sauce, fish sauce, pickles, etc. tapchinuocmy.com

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What Science & Experts Say

Several claims in the article align with known food chemistry, but others require caution. Here’s a more balanced view:

Pepper and Carcinogens?

• Black pepper contains piperine, which at high heat can degrade, but published evidence of pepper turning into cancer-forming compounds under normal cooking is limited.

• Most cooking at home doesn’t reach temperatures that cause major harmful transformations. Still, adding pepper late preserves aroma and volatile compounds.

Salt & Nitrosamines

• Nitrosamines are compounds that may form when nitrates/nitrites interact with proteins under high heat; these are more associated with processed meats than plain iodized salt.

• The claim about salt producing nitrosamines in oil at 180 °C is not well supported in peer-reviewed literature. More commonly, food additives or preservation chemicals may pose nitrosamine risk.

• Iodine loss at high heat is plausible (iodized salt can lose iodine when excessively heated), so seasoning later helps preserve trace nutrients.

Seasoning Timing & Flavor / Texture

• Many chefs and culinary scientists agree: for tender meats, salt added too early can draw moisture; seasoning later helps retain juiciness.

• For vegetables, early salt can draw water, making them soggy—adding near the end often preserves texture.

• For soups and sauces, layering salt (early and just before serving) is common professional practice to build depth and prevent over-salting.

Salt Intake & Health

• The WHO guideline of ≤5 g salt/day is accepted broadly for reducing hypertension risk and cardiovascular disease.

• Hidden sodium from sauces, condiments, and preserved foods are major contributors to excess intake.

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Practical Tips & Safer Seasoning Techniques

To put these ideas into practice safely:

• Season in stages: Use minimal salt early, then adjust with finishing salt near the end.

• Add aromatic spices (pepper, herbs) late to preserve fragrance and reduce chance of degradation.

• Use iodized salt but add some after cooking to preserve iodine content.

• For high-heat cooking (stir-fries), avoid pooling salt in the hot oil—dissolve or mix into sauce first.

• Taste frequently during cooking to fine-tune seasoning rather than overshoot.

• Be cautious with high-salt condiments (soy sauce, fish sauce)—use sparingly and account for their sodium.

• Use low-sodium or alternative seasonings (herbs, acids, spices) to reduce total salt burden.

• Train your palate to prefer less sodium over time—gradual reduction helps adaptation.