Soursop, scientifically known as Annona muricata, comes from the Dutch term "zuurzak" which means sour sack, reflecting the slightly acidic taste of the fruit when ripe. The fruit is also known as "guayabano" in the Philippines, "guanabana" in Spanish-speaking countries, and "durian Belanda”, “durian maki” or “seri kaya belanda" in Malaysia (Badrie & Schauss, 2010; Love & Paull, 2011). The soursop originated in the lowlands of Central America. It was first described by Spanish historian Gonzalo Fernández de Oviedo y Valdés in 1526 and was spread around the world by Spanish explorers.
Annona muricata stands out as a strong, small, tropical evergreen tree that produces the largest fruit within the Annonaceae family. This tree typically reaches up to 10 m in height and thrives in various soil types, but it flourishes best in sandy, well-drained soil with a pH of 5−6. Characterised by its low branches, bushy appearance and upward limbs that shape its slender form, the tree is vulnerable to strong winds and freezing temperatures. With protection from saline spray and sufficient watering, it can be cultivated at sea level and even at elevations up to 914 metres in tropical regions.
Soursop can be found in small family orchards in Southeast Asia, the Philippines, India, Hawaii and other Pacific islands. Orchards often use windbreaks to shield the crops. The tree grows rapidly and usually fruits within 3–5 years after planting. It is currently grown commercially across the tropical Americas. In Malaysia, the production of soursop fruit has increased significantly because of its nutritional and health-protective values. However, the fruit has a short shelf life because it softens quickly after harvest due to a high respiration rate (Chang, 2017).
The fleshy fruit can be oval or heart-shaped, is covered with soft spines and varies in length from a few centimetres to over 30 cm. It is a compound fruit, formed from the fusion of many individual fruitlets. Its irregular appearance may be influenced by insufficient pollination (Love & Paull, 2011). The soursop can weigh up to 4.5 kg (Luzia & Jorge, 2012). The white fruit segments that surround the core seed offer a delightful sub-acid taste. While most segments are seedless, a fertile one contains a smooth, black seed that can be up to 2.5 cm in length. The seeds and bark are deemed toxic due to various harmful compounds, such as anonaine, muricine and hydrocyanic acid, which can cause nausea, vomiting, dizziness, a sudden drop in blood pressure and intestinal problems (Love & Paull, 2011).
Soursop is used to make sorbet, ice cream, mousse, jelly, soufflé and processed or fresh juice. It is made into cakes in Indonesia, and candy in the Philippines, where the young fruit is consumed as a vegetable. In the Caribbean, strained pulp milk of soursop, sugar and juice combined with wine or brandy, is a popular beverage (Love & Paull, 2011).
The soursop is rich in antioxidants, including polyphenols, flavonoids and vitamin C, which help neutralise harmful free radicals in the body and reduce oxidative stress and inflammation (Badrie & Schauss, 2010; Afzaal et al., 2022). These antioxidants can help lower the risk of chronic diseases, such as cardiovascular disease, diabetes and neurodegenerative conditions. In addition, the high vitamin C content in soursop makes it an excellent immune booster by supporting immune function and protecting the body against pathogens.
Annona muricata is classified as Least Concern in the IUCN Red List of Threatened Species because it is easy to cultivate and is not threatened (Botanic Gardens Conservation International (BGCI) & IUCN SSC Global Tree Specialist Group, 2019).
