Kang Sang-muk, the CEO of Gogeumcheonghakdong Yuju Agricultural Association, is a seasoned yuja farmer with 16 years of experience managing the renowned 'Wando Ondam' yuja farm. Covering 12,000 square meters of land, the farm is home to 900 mature trees cultivated using environmentally friendly, low-carbon organic practices. All products marketed by his cooperative, which proudly carries the "Good News" brand, use only organically grown citrons produced through this environmentally conscious method. In organic farming, the term is only meaningful when it encompasses the entire growing process. It adheres to a truly organic approach that ensures the soil undergoes a transformative journey. This commitment means avoiding conventional fertilizers, recognizing that it takes a minimum of 7 to 10 years for existing land to transform into nutrient-rich, naturally fertile soil. Since the end of 2019, marking 11 years of dedicated organic farming, he has produced about 60 tons of robust yuja, securing an annual income of about KRW 200 million. Yuja, a citrus fruit, has more than three times the vitamin C content of lemons, contributing to its reputation as a health-promoting superfood.

During this time, CEO Kang undertook various initiatives to cultivate fertile land. Using a mixture of double-boiled ginkgo, sweet potatoes, oleander, Melia azedarach flowers, and pasqueflower roots in carefully measured proportions, he created a nutrient-rich mixture for the soil. He introduced fermentation processes using deceased fish and EM microorganisms to further improve soil health. Through these conscientious efforts, the once ordinary soil on his citron farm underwent a remarkable transformation, evolving into prime land suitable for organic farming. There are approximately 2,500 yuja farms in Korea, of which only 29 are organic, including six in Wando-gun. CEO Kang's commitment to organic practices is evident in the meticulous certification process. After securing certification for environmentally friendly, pesticide-free agricultural products (5 years), he navigated the conversion period (2 years) to obtain the coveted organic product certification. In addition to the traceability registration of agricultural products and the excellent agricultural product certification, he also proudly obtained the low-carbon agricultural product certification.

After returning to farming in Gogeum-myeon, Wando, in 2008, CEO Kang began establishing a yuja farm 150 meters above sea level. Committed to exploring various methods of low-carbon organic farming, he diligently managed the soil by implementing an annual rotation of antibiotic-free livestock manure compost and fish-based compost. In a unique approach to pest prevention, he refrained from removing grass from the yuja orchard, allowing natural pest predators such as mites to thrive. In recognition of his dedication and expertise, Jeonnam Province honored him as an "Organic Farmer," a distinction reserved for individuals who practice independent and systematic organic farming techniques with more than 5 years of experience.

The Yuja Agricultural Association, led by CEO Kang, was established in November 2011, with five full-time members and 29 associate members (Yuja-producing farmers) and a capital of KRW 150 million. In 2013, all member farms within the association achieved GAP certification. In March 2018, six patents for Ssanghwa-yuja tea were registered, and the association achieved ISO22000 certification in 2019. In the previous year, a total yuja harvest of 340 tons was achieved, including 50 tons of organic yuja, 10 tons of pesticide-free yuja, and 280 tons of regular GAP yuja. The total profit reached KRW 800 million, with KRW 750 million from raw fruit and KRW 50 million from processed yuja products. The annual processing volume ranges from 5 to 10 tons. The association's flagship products include Handmade Yuja Tea, Ssanghwa Yuja Tea, Soybean Yuja Tea, Yuja Powder, Yuja Seaweed Bread, Yuja Coffee, and two gift sets of Handmade Yuja Tea and Handmade Yuja Tea.

The Handmade Yuja Tea stands out in the product lineup, leveraging the distinctive aroma and acidity characteristics, and is priced at KRW 19,800 per kg. The patented Handmade Ssanghwa Yuja Tea complements the unique flavor and aroma of Ssanghwa tea and is priced at KRW 22,000 per kg. Yuja powder, a calorie-free and sugar-free product made by drying and processing citron peel, is available at KRW 13,200 for 100 g. Yuja Sokcheong, a handcrafted citron tea with a unique aroma and tang, is priced at KRW 13,200 for 500 ml. Yuja Tea Bags, made from Ssanghwa Yuja tea, known for its cold-preventing properties, contain various herbal medicines and are available in a box of 20 bags (1.5g each) for KRW 19,800. Another product, citron vinegar, a traditional fermented blend of makgeolli starter and organic citron is sold for KRW 33,000 per 500ml bottle.