No Need to Fry Eggplant in Vinegar or Oil! Japanese Trick Before Cooking 'Guarantees No Discoloration,' Salty, Aromatic, and Tender with Zero Failures

Eggplant is a highly nutritious vegetable, low in fat and rich in antioxidants like anthocyanins. However, one major concern when cooking eggplant is that it quickly oxidizes and turns black after being cut. Additionally, frying or stir-frying often causes it to absorb excessive oil, leaving a greasy aftertaste.

There are various ways to prevent discoloration, but a Japanese farmer recently shared a two-in-one solution: a single step before cooking that prevents both oil absorption and blackening.

How to cook eggplant without it turning black? A Japanese farmer’s pre-cooking step prevents oxidation

A Japanese farmer posted on Twitter: 'If you don’t want eggplant to absorb too much oil when frying or stir-frying, soak it in 1% saltwater for 10 minutes before cooking. This way, it won’t absorb as much oil—highly recommended for a healthier cooking method.'

After soaking, it’s recommended to gently squeeze out excess moisture—never cook it while still wet, as this causes oil splatter. Experts explain that salt draws out moisture, increasing the eggplant’s density. By removing water and disrupting its sponge-like structure, the eggplant absorbs less oil. The post gained over 90,000 likes. One user commented: 'I tried your method for fried eggplant—it really used less oil! Thank you so much!'

In fact, saltwater soaking not only reduces oil absorption but also prevents discoloration. Eggplant flesh turns black when exposed to air due to oxidation of phenolic compounds. Additionally, the skin contains anthocyanins, which are sensitive to temperature and pH. Heating at sub-boiling or smoking-point temperatures can cause darkening. Saltwater acts as a barrier to oxygen, keeping the flesh white—truly a two-in-one benefit.

Eggplant Recipes: Yu-Xiang Eggplant / Spicy Sauce Eggplant

Below are two eggplant recipes that typically require large amounts of oil. Next time you cook them, try soaking the eggplant in saltwater first to reduce oil usage and greasiness.

Yu-Xiang Eggplant

Ingredients: 1 eggplant, 1 tsp minced garlic, 1 green pepper, 100g ground meat, 1 tsp shallot, 1 tbsp salted fish flakes

Marinade: 1 tbsp soy sauce, 1/2 tsp sugar, 1/2 tbsp water, 1/2 tsp cornstarch

Seasoning: 1 tsp yu-xiang sauce, 1/2 tsp sugar, 1 tbsp soy sauce, 4 tbsp water

Instructions:

1. Marinate ground meat with marinade ingredients for 15 minutes.

2. Cut eggplant into strips, stir-fry quickly for 2 minutes, then set aside.

3. Dice green pepper and thinly slice shallots.

4. Pan-fry salted fish until fragrant, then add garlic, shallots, and green pepper to stir-fry. Add pork and mix well.

5. Add eggplant and seasoning, cook for 2–3 minutes until eggplant softens.

6. Add cornstarch slurry, simmer until sauce thickens.

Fail-proof tip: Cut eggplant oxidizes quickly—soak in saltwater immediately to prevent rust-colored discoloration.

Spicy Sauce Eggplant

Ingredients: 2 dried mushrooms, 1/2 tsp sugar, 1 tbsp doubanjiang (fermented broad bean paste), ginger (to taste), 1 tbsp vegetarian oyster sauce, 2 tofu sheets, a pinch of pepper, 1 eggplant, chili (to taste), 50ml water

Instructions:

1. Dice dried mushrooms and tofu sheets, stir-fry in oiled pan.

2. Add sugar, pepper, and doubanjiang to season—set aside as topping.

3. Mince chili and ginger.

4. Cut eggplant into rounds, then into long strips. Score surface with diamond cuts, deep-fry until cooked, then set aside.

5. Heat oil, stir-fry ginger and chili until fragrant, add vegetarian oyster sauce and mix.

6. Add mushroom-tofu mixture and water, stir well, then mix in eggplant and combine.

Fail-proof tip for frying eggplant: To keep eggplant dry and prevent oil splatter, fry the skin side first. High heat creates a barrier against oxidation, preserving its purple color. Finally, mix with toppings—just a quick toss to finish.

Article republished with permission from Hong Kong 01 (Original title: How to Cook Eggplant | Japanese Farmer Shares Method to Break Structure, Prevent Oil Absorption and Discoloration)

Editor: Lam Lai