海蟾宮松花蛋，是修武縣五里源鄉的傳統特產。傳說道士劉海蟾，于五里源村北馬坊泉，令群鴨取松花蛋酬謝仙女（后人在泉畔筑宮），海蟾宮松花蛋由此得名，其歷史悠久。特點是"長存不壞，打開呈固體狀，紅清黑黃，蛋清透明，并有一朵朵狀若松針、晶瑩秀麗的松花圖案，柔軟適中，香氣襲人，食之余香繞口。兼有滋腎陰、狀元氣。祛病去火之功能，為上乘補品。在河南乃至全國享有盛譽。元末以后，歷代皇家都視其為皇宮御宴之美味。
    
    海蟾宮松花蛋問世于宋大定二十五（公元1185年）年，距今已有800年歷史。當地群眾根據石灰可以燒熟雞蛋的道理，反復實踐，終于摸索出制作海蟾宮松花蛋的妙方。每100個鴨蛋，用柏枝、竹葉少許，茴香一錢半，花椒五錢，茶葉一錢半，放在六市斤水中煮沸，將水倒入放有堿面、食鹽、生石灰的溶器內，加入四兩草木灰和成硬泥，均勻地包蛋上，然后裝缸密封，百日即成。
    
    海蟾宮松花蛋之所以能在同類產品中獨具一格，享譽全國，除了其精細的加工方法外，馬坊泉畔的鴨子長期生活在未受污染的水中，多食"活石頭"（燈似瑚珊似的水蟲遺骸，狀若小石子）和魚、蝦等活食，也是一個重要的原因。
    
    近年來，修武縣農科所和各鄉鎮企業，以及馬坊泉畔的十余個村莊，數百戶農民，紛紛從事海蟾宮松花蛋的制作，年產50萬個，但仍供不應求。全國各地來人來函，索取海蟾宮松花蛋的制作方法，海蟾宮松花蛋已在全國各地安家落戶。



    Haichangong Preserved Duck Eggs is a traditional specialty in Wuliyuan, Xiuwu County. It was created in Dasong period of Song Dynasty 800 years ago, when people created this making recipe through trial and error depending on the truth of lime being able to heat eggs to ripe.
      
    In the terms of its characteristics, it can be kept for a long time without getting rotten, has solid red and transparent egg white with needle-liked pictures in it, tastes soft and moderate, smells fragrant, contains medical functions of nourishing females, strengthening males, eliminating diseases and heat, is regarded as a superior tonic. Thus, it enjoys a high reputation in Henan even the whole nation. It has been regarded as a delicious food in imperial feast after Yuan Dynasty.  
      
    Haichangong Preserved Duck Eggs stands out of all the similar products not only thanks to its delicate making technique but also contributes to ducks here are never polluted and mostly eat living stones(water bug remains similar with corals), small fishes and shrimps. In recent years, Haichangong Preserved Duck Eggs has set its position in almost everywhere in our country.