Kung madalas kang magluto at kumain ng hard-boiled egg, marahil ay may mga pagkakataong napansin mong nagkulay grayish o greenish ang egg yolk nito.
Hindi ba dapat yellowish ang kulay ng egg yolk ng nilagang itlog?
Ano ba ang rason kung bakit nagkakaroon ng discoloration? Ligtas pa ba itong kainin?
Okay pa rin ba itong gamitin sa egg sandwich spread, arroz caldo, sopas, at iba pang dishes na may sangkap na nilagang itlog?
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hard-boiled EGGs' YOLK TURNing GRAY explained
Ang dahilan kung bakit nagkakaroon ng discoloration ang egg yolk ay dahil sa init, ayon kay Dawn M. Bohn, PhD, isang associate professor ng Food Science and Human Nutrition Department ng University of Illinois Urbana-Champaign.
Kapag masyadong tumagal sa init ang nilalagang itlog, naaapektuhan ang egg yolk nito at nagkukulay abo na medyo berde.
“When an egg is cooked for too long and/or at too high a temperature, the sulfur in the egg white combines with the iron in the yolk and creates ferrous sulfide, which has a green tint,” paliwanag ng associate professor.
Tinatawag itong denaturation ng mga scientists.
Pero saad sa report, hindi lang ito nangyayari sa hard-boiled eggs.
Kapag malakas ang apoy, nagkakaroon din ng grey color ang scrambled eggs at omelet.
Nagdetalye naman ang University of Nebraska – Lincoln kung paano nangyayari ang discoloration sa egg yolk.
Anito: “A greenish-gray ring may appear around a hard-cooked egg yolk. It's unattractive, but not harmful.
“The ring is caused by a chemical reaction involving sulfur (from the egg white) and iron (from the egg yolk), which naturally react to form ferrous sulfide at the surface of the yolk.
“The reaction is usually caused by overcooking, but can also be caused by a high amount of iron in the cooking water.”
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IS IT SAFE TO EAT it AN EGG WITH GRAY OR GREENISH YOLK?
Ang next important question, ligtas pa ba itong kainin kahit kulay greenish-gray na ang egg yolk?
Ang sagot ay oo.
Katuwiran ni Stephanie Smith, PhD, isang assistant professor mula School of Food Science ng Washington State University, mas ligtas pa nga itong kainin kumpara sa undercooked eggs.
Mas tiyak kasing walang bacteria kapag overcooked ang nilagang itlog.
Dagdag pa ni Smith: “The ferrous sulfide that’s formed when the egg is overcooked is actually the same form of iron you find in iron supplements.”
Kung gusto mo namang iwasan ang discoloration ng egg yolk ng hard-boiled eggs, huwag i-overcook ang itlog at palamigin agad ito matapos hanguin.
Maaari itong ibabad agad sa malamig na tubig para matigil ang carryover cooking nito.
Puwedeng ilagay sa refrigerator ang hard-boiled eggs matapos palamigin.
Maaaring magtagal ng isang linggo sa ref ang hard-boiled eggs basta hindi pa binabalatan.
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