Fuyang Walnuts

Fuyang Walnuts

　　Fuyang walnuts are a specialty of Fuyang County, Linyi City, Shandong Province. The main varieties grown in Fuyang include Yuanfeng, Xiangling, Fenghui, and Luguang. Their common characteristics are large size, thin shells, high kernel yield, and attractive, simple brown patterns on the surface.

　　Walnuts are woody oil-bearing fruit trees that are hardy, drought-resistant, and well-suited to growth in limestone mountainous areas. The southern limestone mountainous region of Fuyang, primarily in Shaoyao Mountain Township, has particularly favorable conditions for walnut cultivation. With over 500 years of planting history, some walnut trees from the Ming and Qing dynasties still exist today. The local community has a long tradition and rich experience in growing walnuts. Currently, the walnut cultivation area has expanded to over 40,000 mu (approximately 2,667 hectares), with around 3 million trees. The main varieties include Yuanfeng, Xiangling, Fenghui, and Luguang. Their common characteristics are large size, thin shells, high kernel yield, and attractive, simple brown patterns on the surface.

　　Walnuts are highly nutritious. According to analysis by the Shandong Academy of Fruit Tree Research, 100g of edible walnut contains 2.55g of total sugars, 16.51g of protein, 68.70g of fat, 319.9mg of phosphorus, 377.6mg of potassium, 101.4mg of calcium, 2.38mg of iron, 2.70mg of zinc, and 17 types of amino acids. The total amino acid content in walnut kernels is higher than that of soybeans and peanuts, giving them special nutritional value. The nutrition provided by one jin (500g) of walnut kernels is roughly equivalent to that of 0.5kg of eggs, 2.3kg of beef, and 4.7kg of milk. China’s Pharmacopoeia records that walnut kernels can warm the lungs, calm wheezing, nourish kidneys, and consolidate essence. They are used to treat deficiency-cold, wheezing cough, weak knees, seminal emission, and impotence. Walnut kernels also have brain-boosting and longevity-promoting benefits. The "Compendium of Materia Medica" states that walnuts can “build qi and nourish blood, moisten dryness and resolve phlegm, benefit the life gate, aid the triple burner, warm the lungs and intestines,” making them one of the three major dried fruits used for tonic purposes (along with red dates and longan).

　　Walnuts are known as an oil-bearing woody species. The oil yield of walnut kernels is about 65%. Walnut oil (at 25°C) has a specific gravity of 0.9235, a refractive index of 1.475, an iodine value of 161.7, an acid value of 5.1, a saponification value of 194.5, and non-saponifiable matter of 0.5%. The fatty acids in walnut oil are mainly unsaturated ones such as oleic acid, linoleic acid, linolenic acid, and arachidonic acid, accounting for over 90% of the total, with the beneficial linoleic acid making up more than 70%. Therefore, walnut oil is considered a premium edible oil.

　　The wood of Shaoyao Mountain walnut trees is hard, with fine grain, minimal shrinkage, strong resistance to impact, no warping or cracking, insect resistance, and a beautiful luster. It can be used to make high-grade plywood and military supplies. Its bark, leaves, and green husks can be used to extract tannic acid and tannin glue. The roots can be processed into brown pigment. The outer fruit skin can be burned to produce alkali, with potassium phosphate content exceeding 60%, making it suitable as a raw material for chemical, pharmaceutical, and light industries. Walnut leaves boiled in water mixed with soap solution can serve as a pesticide for pest control, and the shells can also be baked into activated carbon for anti-toxic use.

　　Shaoyao Mountain walnut trees are relatively low-maintenance woody fruit trees that are drought-resistant and flood-tolerant, with stable yields. Trees that are over 20 years old can typically yield around 50kg per year, making them a sought-after dried specialty nut in the market.

　　Currently, Fuyang is focusing on developing walnut production with Shaoyao Mountain at its core, establishing a 100,000-mu walnut production base in the limestone mountainous region that includes towns such as Mazhuang, Tan Yi, Xinzhuang, and Feicheng.