Introduction

Throughout the long history of survival and development, mankind has developed a close relationship with plants [1]. Approximately 13% genera of vascular plants are available as dietary food, followed by ornamental plants (26%) and medicines (16%) [2]. As the archetype of biocultural diversity, food plants establish a connection between the environment and biodiversity, while also bridging human society with cultural richness [3]. Numerous edible flowers are integral to the gastronomic heritage of various countries and play a crucial role in human nutrition and food security [4,5,6,7].

Edible flowers (EFs) are broadly defined as plants in which entire flower organs or their components are deemed edible. These flowers serve various purposes, such as in medicine, flavor extraction, and as essential ingredients within the food and medicinal sectors [8, 9]. It is reported that there are 180 species of common EFs, belonging to 97 families and 100 genera, globally consumed in all kinds of food and drinks [10]. Research and review articles on its nutritional and phytochemical elements have always increased [11]. Studies show that many EFs are rich of protein, vitamins, minerals, fiber and carbohydrates. A total of 302 bioactive compounds including flavonoids, terpenoids, phenylpropanoids, alkaloids and organic acids, with 22 biological activities were summarized [47]. We also investigated some of the flowers sold in the ** purposes in the majority of people's perception [8, 14, 50]. Even in catering, flowers serve to enhance sensory pleasure through their appearances and aroma, though they are often perceived as inedible [9]. In China, the culture of flowers is characterized by the ornamental function and various beautiful implications [51]. Eating flowers is always on the edge of the culture and food system, existing in the rural and indigenous foodscape in China [52]. Among the urban populations, the concept of flower-eating culture is relatively novel, drawing attention due to its unique ability to provide both nourishment and spiritual enrichment to humanity. It also offers a fresh perspective in contrast to consuming leafy vegetables, presenting the potential to contribute to a health-conscious way of living.

The nutritional, phytochemical and pharmacological studies on some representative EFs in **shuangbanna partly justify the use of EFs by local people and reveal their potential to be exploited. The flower of Gmelina arborea is rich in nutrition with various amino acids, minerals, sugars, fiber and trace elements such as selenium. It also has excellent hypoglycemic and antibacterial activity [53]. Pigment extracted from it has good properties and is non-toxic and odorless [54]. Musa acuminata inflorescence has high total phenolic content with significant free radical scavenging activity and good antioxidant capacities [55]. Buddleja officinalis inflorescence contains flavonoids, phenylethanols, terpenoids, alkaloids and volatile oils, which have a variety of pharmacological activities such as antioxidant, antibacterial, anti-inflammatory, neuroprotective and immunomodulatory [56]. The cake made from G. arborea flowers was a widespread delicacy, easily accessible in markets. It held great significance as a staple during the Dai New Year celebration, known as the water splashing festival. During its preparation, Dai women combined dried flower powder (referred to as Maisuo in Dai language) with glutinous rice powder, brown sugar or white sugar, sesame seeds, peanuts, and vegetable oil. The amalgamation was then shaped into cubes, enveloped in banana or Phrynium leaves, and steamed in a wooden pot. This steamed cake, called Khaonuosuo by the locals, could be stored at room temperature for around a week due to the bioactive properties of Maisuo, which exhibits antibacterial effects [38, 39].

In fact, studies on the factors influencing consumers’ attitudes toward the EFs’ consumption showed that health benefits are not the most important reason why people consumed EFs [57]. The cultural factors and specific curiosity have great influences on attitudes toward the consumption of EFs according to the survey in three different countries (Portugal, Slovenia, and Brazil), respectively [57], and in Taiwan of China [58]. Whatever the motivation, it is no doubt that there is a huge market for flower-eating to be explored. A questionnaire survey conducted in Portugal, where there is little flower-eating culture, showed that flowers can be popular in gastronomy [59]. As an unfamiliar food in South America, consumers showed a positive attitude to food with flowers either for eating or for decoration [60].

The local farmers’ markets as well as supermarkets provide EFs and derivative products as bridges linking EFs with consumers. The consumption of flowers holds significant importance in the diet of individuals residing in **shuangbanna. This flower-centric culinary culture has consequently led to the development of associated products. Within local supermarkets, canned pork products are specifically labeled as 'suitable for preparing Musa inflorescence' on their packaging. The potential of the EF market lies not only in the development of food and drug products based directly on EFs as materials. It lies also in the creation of more derivative products in the whole EFs knowledge system based on a common perception and a wide range of users.

Though the EFs market has become increasingly promising, toxicity treatment is an issue to be raised [9]. Various toxic and anti-nutritional constituents, including trypsin inhibitors, hemagglutinins, oxalic acid, cyanogenic glycosides, and alkaloids, have been detected in the floral structures[8]. In this study, 29 EFs (13.7%) should be pre-processed by boiling or blanching in hot water, or removing peels and some parts before cooking and eating. Although the locals do not know the exact toxic ingredients, they have traditional knowledge to ensure their safety. Toxicological studies on these EFs can identify specific toxic components or discover novel toxic components that will contribute to consumption safety.

Chinese food is now shifting from traditional cuisine toward more meat and processed foods [61]. It is time to pay attention to healthy eating including the plant-based dietary trends worldwide [62]. Research has established the advantages of plant-based diets for China’s aging population [63]. Combining plant-based food with local production would be an advantageous approach [64], suggesting that EFs could play a substantial role in enhancing the local food system and providing potential solutions to societal challenges such as aging and health-related concerns.

Conclusion

Through the ethnobotanical survey, 212 species and varieties of edible flowers from 58 families along with a variety of related traditional knowledge in **shuangbanna were recorded and summarized. Local people are knowledgeable about which EFs are safe when consuming, how to process them by removing toxicity or bitterness, and whether they can be cooked with other parts of the plant. The traditional knowledge on usage of EFs is the main and representative element of flower-eating culture, but it is gradually diminishing. The preservation and further scouting of traditional knowledge of edible and medicinal flowers are critical because of their biocultural significance and great potential for markets, scientific research and industrial exploitation. The practice of consuming flowers, rooted in local traditions, serves as a bridge between tradition and modernity. This flower-eating culture has the potential to promote the conservation of biocultural diversity, healthier food systems and sustainable development in the future. As such, policymakers are able to consider initiatives to support the documentation, conservation, and revitalization of this cultural heritage, recognizing its potential benefits for both local community and broader societal contexts.