What Do You Know About Passion Flower Products?

Passion fruit, also known as passionflower, Brazilian fruit, passion fruit, egg fruit, and passion fruit, is a plant belonging to the Passiflora genus of the Passifloraceae family. It is native to South America and primarily distributed in tropical and subtropical regions. It is now cultivated in Guangxi, Guangdong, Jiangxi, Fujian, Sichuan, Yunnan, and Taiwan in China [1]. Passion fruit has a short growth cycle, high yield, good economic returns, and broad adaptability. In 2011, its cultivation area nationwide was less than 700 hectares, but by early 2019, it had rapidly expanded to over 30,000 hectares across various cultivation regions in China [2].

Passion fruit is highly adaptable, grows quickly, is easy to cultivate, and has few pests and diseases. It can be grown in farmland, dry land, and residential areas. There are numerous passion fruit varieties, with the most commonly cultivated edible types including purple-fruited passion fruit, camphor-leaved passion fruit, yellow-fruited passion fruit, large-fruited passion fruit, sweet-fruited passion fruit, and banana passion fruit, among six main varieties [1].

In addition to traditional culinary uses, passion fruit possesses nutritional, health-promoting, and medicinal properties. As research into its functional properties deepens, studies on processing technologies leveraging its unique flavor and nutritional value are also increasing. By introducing the functional characteristics of passion fruit in terms of edibility, nutrition, and medicinal properties, and summarizing the research progress on processing technologies for passion fruit-based products such as juice, wine, preserves, and powder, this study aims to provide references for the development of China's passion fruit industry.

1 Research Progress on the Functional Characteristics of Passion Fruit

Passion fruit is sour and sweet, nutritious, and versatile. In addition to the general characteristics of fruits, it also possesses antibacterial, antioxidant, and anti-anxiety functions, which are closely related to the bioactive components it contains.

1.1 Edible Functions

Passion fruit has a unique taste, is juicy and aromatic, and is widely popular among consumers. In recent years, passion fruit has seen rapid development in the food and beverage industry, with various products such as composite juices, jams, wines, vinegars, and preserves available in the market.

Passion fruit weighs 30–50 g, with seeds accounting for approximately 10% of the fruit's weight. The seeds contain 28.2% oil, and the oil content of the seed kernels exceeds 60%. The unsaturated fatty acid content in passion fruit seed oil reaches over 80% [3]. Passion fruit is delicious and juicy with a unique flavor, and its fruit contains the aromas of over 100 fruits such as papaya, pomegranate, pineapple, mango, and banana, making it an ideal raw material for beverage products and earning it the title of “King of Juices.” Yang Feng et al. [4] found that passion fruit juice has a high soluble solids content of 16.5% and good chemical stability at high temperatures, making it an excellent raw material for juice processing.

Passion fruit peel accounts for 50–55% of the fruit's weight and is rich in pectin, making it suitable for making candied fruits and jams. Passion fruit seeds have a rich fatty acid composition. Nyanzi S A et al. [5] conducted a comparative study on the fatty acid composition of yellow passion fruit seed oil, confirming that passion fruit seed oil is an excellent source of essential unsaturated fatty acids. Zhang Jingbo et al. [6] found that passion fruit seeds primarily contain two types of unsaturated fatty acids: linoleic acid and oleic acid, with linoleic acid accounting for over 72%. Passion fruit contains various aromatic components.

Kuang Ruibin et al. [7] analyzed four varieties of passion fruit and found that their aromatic components exhibit certain similarities. A total of 153 components were identified across the four varieties, including 61 esters, 29 alcohols, 19 alkenes, ketones (12), acids (9), alkanes (6), aldehydes (5), and heterocyclic compounds and other substances (12). Janzantti S J et al. [8] isolated volatile compounds from passion fruit, separated them using high-resolution gas chromatography, and evaluated them using OSME (olfactory measurement technology), identifying a total of 64 aromatic compounds that can be used as flavorings in pastries and other foods to develop high-quality products.

1.2 Nutritional Functions

Passion fruit is rich in nutritional value. Guo Yanfeng et al. [9] determined the nutrient content of different passion fruit varieties and found that there were significant differences in nutrient composition among different varieties. Golden fruit juice had higher protein and mineral content than Purple Fruit No. 1 and Taiwan Agricultural No. 1, while Purple Fruit No. 1 juice had the highest vitamin C content, and Taiwan Agricultural No. 1 had the highest crude fat and total sugar content. Additionally, passion fruit not only contains nutrients such as protein and minerals but also flavonoids, 17 amino acids, and 165 beneficial substances for the human body, including fat, calcium, phosphorus, iron, potassium, and SOD enzyme.

1.2.1 Vitamins

Passion fruit is rich in vitamins. Guo Yanfeng et al. [9] measured the vitamin C content of different passion fruit varieties at 12.33–13.47 mg/100 g, vitamin B content of 60.07–0.15 mg/100 g, and vitamin A content of 0–0.024 mg/100 g. The vitamin C content in passion fruit is higher than that in other fruits, hence it is referred to as the “vitamin C king” among fruits. Vitamin C has the function of enhancing human resistance and improving immune function. Additionally, Yuan Qifeng et al. [10] used high-performance liquid chromatography to determine that passion fruit also contains vitamins A, B1, and E, which have special physiological functions and help maintain normal metabolic processes in the human body.

1.2.2 Flavonoids

Passiflora flavonoids exhibit good antioxidant activity, with a higher scavenging rate for ·OH (hydroxyl free radicals) and O2- (superoxide anion free radicals) compared to vitamin C at the same concentration [11]. Mareck U et al. [12] used HPLC (high-performance liquid chromatography) to identify the presence of apigenin-6-C-glucoside-8-C-arabinose, apigenin-6-C-arabinose-8-C-glucoside, luteolin-6-C-glucoside, luteolin-8-C-glucoside, and apigenin-6-C-glucoside, among which luteolin-6-C-chinovoside and luteolin-6-C-fucoside have not been reported in previous literature.

García-Ruiz A et al. [13] identified and quantified 18 types of flavonoids, 9 types of anthocyanins, and 9 types of flavan-3-ol monomers through separation and identification, and found that the fruit of Passiflora edulis is rich in flavonoid compounds, diverse, with significant differences in content among different plant parts. Among these, flavonoids were primarily represented by flavonoid-triol monomers and proanthocyanidins. Ferreres F et al. [14] used HPLC-DAD-MS/MS (high-performance liquid chromatography - diode array detection - tandem mass spectrometry) to identify flavonoids in passionflower leaves, indicating that passion fruit leaves exhibit excellent antioxidant activity against DPPH free radicals, superoxide anion free radicals, hydroxyl free radicals, and hypochlorous acid, with a concentration-dependent effect.

1.2.3 Amino acids

Amino acids are one of the most basic substances in the human body and the material basis of life metabolism, closely related to biological life activities. Passionflower contains a wide variety of amino acids in abundant quantities. Kuang Ruibin et al. [7] detected 17 amino acids in passionflower fruits using an amino acid analyzer, including 2 essential amino acids for children, seven essential amino acids for humans, and eight other amino acids. Among these, glutamic acid content reached 204.00–256.00 mg/100 g, accounting for 19.93% of the total amino acid content, and there were significant differences in amino acid types and content among different passion fruit varieties. Deng Boyi et al. [15] demonstrated that passion fruit contains a rich variety of amino acids. He Jie et al. [16] used an automatic amino acid analyzer to determine the amino acid components in passion fruit and found that aspartic acid and glutamic acid play an important role in the flavor of purple passion fruit.

1.2.4 Other Nutritional Components

Passion fruit contains various essential elements necessary for maintaining human life activities. Passion fruit is rich in calcium, magnesium, and potassium. Zhang Limin et al. [17] analyzed and determined that every 100 g of passion fruit contains 455.00 mg of calcium, 34.00 mg of magnesium, and 523.00 mg of potassium. Additionally, passion fruit contains essential trace elements such as iron, zinc, selenium, and copper, which are minerals commonly found in most tropical fruits [18]. Deng Boyi et al. [15] used passion fruit, wax apple, and green jujube as research subjects and found that the content of major elements such as iron, manganese, and zinc in passion fruit was the highest among the three, at 0.39, 0.11, and 0.46 mg/100 g, respectively. Additionally, the SOD content in passion fruit was also the highest among the three.

1.3   Functional Properties Research Progress

As scientific research on passion fruit has deepened, numerous scholars have discovered that passion fruit possesses antibacterial, antioxidant, and anxiolytic effects, providing a theoretical basis for the development of passion fruit-based health foods.

1.3.1   Antibacterial Activity

The extracts from various parts of passion fruit contain multiple active components that can inhibit the growth of certain bacteria. Cen Chunyi et al. [19] used the pathogen growth rate method to treat three types of bacteria (Pueraria lobata black spot disease, anthracnose, and anthracnose) with different concentrations of fresh passion fruit leaf, stem, and fruit extracts. The results showed that the water and ethanol extracts of passion fruit exhibited good inhibitory activity against Pueraria lobata black spot disease, anthracnose, and anthracnose. anthracnose. Xu Xiaojing [20] used the filter paper diffusion method to study the inhibitory effects of yellow passion fruit seed oil and purple passion fruit seed oil on five bacteria: Escherichia coli, Staphylococcus aureus, Salmonella, Shigella, and Pseudomonas aeruginosa, and found that all exhibited inhibitory effects, with yellow passionflower seed oil exhibiting weaker inhibitory activity than purple passionflower seed oil.

Additionally, passionflower polysaccharides exhibit good antibacterial efficacy. Zhang Shuai et al. [21] found that passionflower shells contain numerous polysaccharide components with strong antibacterial activity. Zheng Mingluan [22] studied the antibacterial activity of passionflower fruit shell polysaccharides and discovered that these polysaccharides have good inhibitory effects on yeast and bacteria but weaker inhibitory effects on fungi.

Chen Yingshan [23] extracted purple passion fruit peel, pectin, and polysaccharides using a mixed acid method, demonstrating that purple passion fruit peel, pectin, and polysaccharides can effectively improve colitis-induced intestinal mucosal inflammation in rats by regulating inflammatory factors. Dai Yichuang et al. [24] conducted plate inhibition tests and found that passion fruit pulp juice exhibited significant antibacterial effects against six common foodborne pathogens (Staphylococcus aureus, Listeria monocytogenes, Salmonella enteritidis, Bacillus cereus, Shigella flexneri, and Escherichia coli O157:H7). Rotta E M et al. [25] found that polyphenol extracts obtained from passion fruit seeds may enhance the oxidative stability of beverages containing w-3 fatty acids and exhibit certain antibacterial effects.

1.3.2 Antioxidant Effects

With the improvement of living standards, people are increasingly consuming foods rich in antioxidant components, particularly those with antioxidant and anti-aging functions. Some scholars have found that carotenoids and polysaccharides in passion fruit seeds and pulp, as well as anthocyanins in the peel, exhibit excellent antioxidant capacity. Additionally, studies have shown that the peel, pulp, and juice of passion fruit possess strong antioxidant activity, which is attributed to their high content of flavonoid compounds [26].

Ferreira B S et al. [27] found that passion fruit seed oil possesses certain antioxidant activity. Wang Qinfeng et al. [28] used HPLC detection methods to quickly extract and measure lutein and β-carotene in passion fruit pulp. These abundant carotenoids can be converted into vitamin A in the human body, thereby exerting antioxidant effects. He Yinjue et al. [29] demonstrated that passion fruit pulp polysaccharides possess the ability to scavenge DPPH free radicals and hydroxyl free radicals. The anthocyanins present in passion fruit peel also exhibit antioxidant effects. He Dan et al. [30] identified 12 anthocyanins in purple passion fruit peel with significant antioxidant activity. Additionally, Xu Haitang et al. [31] measured the inhibitory effect of passionflower leaf polyphenols on α-glucosidase, indicating that passionflower leaf polyphenols exhibit good antioxidant activity.

1.3.3 Anxiolytic Effects

Anxiety neurosis, commonly referred to as anxiety disorder, is a neurotic disorder often accompanied by autonomic nervous system symptoms and motor tension, characterized primarily by persistent, generalized anxiety or recurrent episodes of panic and restlessness. In recent years, domestic and international researchers have studied passionflower as an object of research, investigating its anxiolytic active components and mechanisms of action. Zhao RuiRui et al. [32] suggested that GABA (γ-aminobutyric acid), benzofuran, γ-carboline alkaloids, poplar extract, and lipophilic substances are the components in Passiflora plants with anxiolytic activity, and their mechanisms of action are related to the effects of the GABA-benzodiazepine receptor complex, monoamine oxidase inhibition, and aromatase inhibition.

Zou Jiangbing et al. [33] used the elevated plus maze test as an animal model and found that the leaf extract of Passiflora indica exhibits significant anxiolytic effects, with its mechanism of action potentially related to regulating the expression levels of mRNA for GABAA (γ-aminobutyric acid A-type receptor) subtype mRNA expression levels. Elsas S M et al. [34] demonstrated in vitro using rat hippocampal pyramidal neurons that GABA, which is rich in passionflower plant extracts, can induce GABAA receptors to produce inward currents, thereby producing a sedative effect.

1.3.4 Other functions

In addition to the above functions, passionflower also possesses other functions, such as anticancer, and promoting metabolism. Takayuki Y et al. [35] investigated the anticancer effects of PFSE (passionflower seed extract) on two human cancer cell lines, NCI-H 522 cells (highly expressing GLOI [glutathione S-transferase I]) and HCT 116 cells (lowly expressing GLOI). PFSE and its its diphenyl ethyl components inhibit GLOI activity.

Araujo M H D et al. [36] isolated β-amyrin triterpenes from the Passiflora genus, which can be used in new methods for treating severe tuberculosis, aiming to reduce inflammatory responses, and suggested that the flavonoids present in Passiflora have potential for treating tuberculosis. Passion fruit peel accounts for 50%–55% of the total fruit weight, with total dietary fiber content reaching 73% of the dry peel weight [37]. Dietary fiber functions include promoting excretion, removing stagnant and adherent irritants from the intestines, lowering blood glucose and serum cholesterol levels, regulating gastrointestinal function, and aiding in the treatment of cardiovascular diseases [38]. To optimize the application of passion fruit dietary fiber in food, Jiang Wentao et al. [39] used DHPM (dynamic high-pressure microjet technology) to reduce the secondary particle size of passion fruit peel dietary fiber, achieving a micron-level size, thereby providing a theoretical basis for the high-value application of passion fruit peel.

2  Research Progress on Passion Fruit Processing Technologies

Passion fruit is widely loved for its unique taste and rich nutritional value. Various passion fruit-related foods continue to innovate, and processing technologies leveraging its nutritional value are constantly updated in the market. Products such as wine, juice, and dried fruit with the unique flavor of passion fruit are highly favored by consumers.

2.1   Extraction Processes for Bioactive Compounds

Extracting substances such as pectin, flavonoids, and seed oil from passion fruit significantly enhances its utilization rate. Passion fruit pectin is a water-soluble polysaccharide widely present in passion fruit. Li Ying et al. [40] employed a synergistic ultrasound-microwave method to extract pectin from dried passion fruit peel, determining the optimal process parameters as a solid-to-liquid ratio of 1:30 (g:mL), a water bath at 60 min, a temperature of 50°C,  pH 2.0, ultrasonic power 50 W, microwave power 600 W, and ultrasonic-microwave time 8.0 min, yielding pectin at 12.14% ±0.06%.

Abboud K Y et al. [38] demonstrated that PFPP (passion fruit peel polysaccharide) has different properties from commercial HMP (high-methoxy pectin), as it does not require sucrose or low pH to form a gel, but rather enhances the application of passion fruit peel as a soluble dietary fiber and pectin in various products such as low-sugar products. Other researchers employed microwave extraction [41] and steam explosion processing [42], which, compared to traditional acid methods, demonstrated higher extraction efficiency without affecting pectin quality. Yang Cui-Feng et al. [43] found that the optimal conditions for flavonoid extraction from passion fruit peel were 70% ethanol volume fraction, a solid-to-liquid ratio of 1:15, and ultrasonic extraction for 33 minutes, yielding an extraction rate of 1.321%. During passion fruit processing, a significant amount of residues are generated, such as passion fruit seeds, which account for approximately 5% of the fruit's composition and contain about 30% oil.

Ning Xing et al. [44] used an ultrasonic-assisted solvent extraction method with passion fruit seeds as the study object to extract passion fruit seed oil with a content of 24.7%. with optimal extraction conditions of ultrasonic temperature 35°C, ultrasonic time 39.3 min, ultrasonic power 160 W, and solid-liquid ratio 1:16 (g:mL). Liu Songqi et al. [45] extracted passion fruit seed oil using a water-enzyme method, optimized specific process parameters using response surface methodology and mixture design, and investigated the effects of pH value, solid-liquid ratio, and other factors on seed oil extraction rate. The optimal extraction process determined yielded oil with good color and excellent DPPH radical scavenging activity.

2.2 Juice

In recent years, there has been significant research on passion fruit juice, primarily focusing on juice processing technology and the production of composite beverages. Moura C D M et al. [46] used mangosteen as a flavoring agent and added passion fruit peel powder to a beverage, which exhibited high sensory acceptance and enhanced the nutritional and processing quality of the dairy beverage. Zheng Xinyao et al. [47] produced a high-nutrient composite grain beverage using a ratio of 35% barley juice, 15% buckwheat juice, 10% xylitol, 10% passion fruit juice, and 0.05% citric acid.

Zhang Dan et al. [48] formulated a composite beverage with a volume ratio of goji berry juice to passion fruit juice of 75:25, and added 0.06 g/100 mL citric acid and 8 g/100 mL white sugar. Zhao Wenqing et al. [49] used pear cactus and passion fruit juice as raw materials, and through response surface experiments and orthogonal experimental design, optimized the stability and formulation of a passion fruit cactus mixed fruit and vegetable beverage. Wei Jinnna et al. [50] investigated the production process of passion fruit milk beverages, using single-factor experiments and orthogonal experiments to determine the optimal process for passion fruit lactobacillus beverages. The resulting beverage was smooth and delicious, with the distinctive aroma of passion fruit and fermented milk. Zeng Yupeng et al. [51] developed a juice drink with a unique moringa flavor and passion fruit-layered texture using moringa leaf extract and passion fruit juice as the main ingredients. Additionally, there are composite beverages such as passion fruit-pear composite juice [52] and passion fruit-star fruit composite juice [53].

2.3 Fruit Wine

Passion fruit wine is made primarily from passion fruit juice through yeast fermentation to break down sugars, resulting in a distinctive passion fruit flavor. Fang Xiaochun et al. [54] selected six types of active dry yeast for fermentation to produce passion fruit wine, finding that under fermentation conditions of 25°C,  yeast inoculum of 0.1%, and initial sugar content of 25.6 Brix, the fermentation capacity was strongest and the sensory score was highest for Angel RW active dry yeast, with the best quality of passion fruit wine achieved when the raw juice content was 50%. Cheng Yafang et al. [55] noted that passion fruit is rich in flavor compounds but has low juice extraction rates and low sugar content with high acidity, while sugarcane juice has a mild flavor but contains sufficient fermentable sugars. Combining the two can create a complementary fruit wine.

Currently, there are commercially available passion fruit juice wines; however, due to low peel utilization rates, no passion fruit whole fruit wines have been reported. Cheng Hongzhen et al. [56] used single-factor experiments combined with response surface methodology to determine the optimal fermentation process for whole passion fruit wine: yeast inoculation rate of 0.04%, fermentation time of 5 days, initial sugar content of 21%, and fermentation temperature of 29°C, achieving a breakthrough in passion fruit wine processing technology. Cheng Hao et al. [57] optimized the fruit wine fermentation process by first conducting single-factor experiments to investigate the effects of three key factors—fermentation temperature, initial pH of the fermentation broth, and inoculation rate—on changes in sugar content in the fermentation broth. Based on these results, they designed orthogonal experiments to further optimize the process, ultimately determining the optimal fermentation process for fruit wine.

2.4 Fruit Vinegar

Fruit vinegar is rich in organic acids, minerals, and various amino acids, possessing abundant nutritional value. Some scholars have combined passion fruit with other fruits to develop various passion fruit vinegar products, such as snow lotus fruit-passion fruit composite fruit vinegar [58] and banana-passion fruit composite fruit vinegar [59]. Wang Zhi Jiang et al. [60] developed a passion fruit yam composite fruit vinegar with a DPPH radical scavenging rate of 97.5% and high antioxidant properties. Kang Chao et al. [61] optimized the passion fruit persimmon fruit vinegar process through factor analysis, single-factor experiments, and response surface methodology, with Bacillus subtilis inoculation at 11%, initial alcohol content at 7% vol, rotation speed of 166 r/min, fermentation temperature of 30°C, and fermentation time of 10 days, resulting in a total acid content of 5.37 g/100 mL in the passion fruit composite fruit vinegar. Wang et al. [62] optimized the fermentation process of persimmon fruit vinegar through orthogonal experiments and single-factor experiments, ultimately obtaining a total acidity of 0.53 ± 0.08 g/100 mL and total sugar content of 6.95% in passion fruit persimmon fruit vinegar.

2.5 Yogurt

Compared to vegetable and grain yogurt, passion fruit is rich in nutrients and has a unique “hundred-fruit aroma,” making it an ideal raw material for flavored yogurt production. Passion fruit yogurt features a harmonious balance of color, aroma, and taste, and its nutritional profile is more comprehensive. Zhou Xianjiao et al. [63] used PBD (Plackett-Burman design) experiments, steepest slope experiments, and single-factor experiments with fermentation temperature, juice addition, and white sugar addition as independent variables. Through response surface optimization, the optimal fermentation process for yogurt was determined as follows: white sugar addition of 7.4%, yeast inoculation of 0.1%, passion fruit juice 5.5%, fermentation time 5 hours, and fermentation temperature 42.7°C.

Huang Li et al. [64] used passion fruit and carrot as raw materials and determined the optimal formulation for passion fruit-carrot composite yogurt as follows: carrot juice addition 23%, passion fruit juice 4.5%, white sugar 9%, lactic acid bacteria 0.5%, and a composite stabilizer of xanthan gum and sodium carboxymethyl cellulose (1:1) 0.1%. Currently, most yogurt products on the market contain stabilizers. Jiang Wei [65] utilized the aromatic fragrance, sour-sweet taste, and digestive benefits of passion fruit to develop a high-protein, fruit-flavored yogurt without added stabilizers through single-factor experiments and orthogonal experiments, providing a theoretical basis for the industrial production of passion fruit yogurt.

2.6 Dried fruit

Currently, passion fruit processing primarily focuses on the fruit pulp, with few processing methods for the peel by-products. This is because the outer layer of passion fruit is hard and smooth, making it difficult to process, and the peel is typically discarded during processing. Zeng Fan [66] processed passion fruit peel from the “Purple Fragrance No. 1” variety into fruit leather after water boiling and brining. The fruit leather had moderate sweetness, without bitterness, greasiness, or astringency. Huang Guitao et al. [67] conducted orthogonal experiments and single-factor experiments using peel as raw material and juice as the permeating solution, determined the optimal processing conditions for passion fruit candied peel as follows: citric acid addition of 0.75%, pre-boiling time of 70 minutes, sugar boiling time of 20 minutes, sugar penetration time of 17 hours, and baking at 60°C for 4.75 hours. The final product exhibited good sensory properties and high plumpness.

2.7 Other

In addition to developing products such as juice, vinegar, and candied fruit, many researchers have utilized passion fruit to develop products such as jelly, peel powder, and fruit cakes. For example, Siringoringo M T et al. [68] conducted a completely randomized factorial study on Dutch eggplant and passion fruit jelly under 7% citric acid and 80% sucrose conditions, finding that the sensory value was high and the quality was the best. Silva E CO D et al. [69] studied the physicochemical properties of passion fruit powder, recommended 80°C as the optimal temperature for soaking and drying. Garcia M V et al. [70] incorporated passion fruit peel powder as an ingredient into cookies, and the results indicated the feasibility of replacing flour with passion fruit peel powder (30% passion fruit peel powder) and its potential as a nutritional fortifier for dietary foods. Zou Shiping et al. [71] mixed passion fruit juice (debittered and de-astringent) with flour, egg batter, and other ingredients to create a high-nutrient, flavorful health cake. Zhao Ye et al. [72] added passion fruit juice to low-gluten flour and incorporated appropriate additives to develop a new product with a unique flavor and excellent quality in the category of puff pastries.

3 Conclusion

Passion fruit has a unique flavor, is rich in nutrients, and possesses the combined aroma of multiple fruits, making it highly promising in the market. Based on the above studies, passion fruit juice, pulp, and seeds all have excellent edible value. Additionally, passion fruit contains abundant nutrients such as vitamins, flavonoids, and amino acids, as well as functional properties including antibacterial and antioxidant effects. In the market, processing technologies utilizing passion fruit's value are constantly being updated, and products such as fruit wine, juice, vinegar, yogurt, and dried fruit with passion fruit's unique flavor are widely popular among consumers.

Currently, there are still some issues in the development and processing of passion fruit products: on one hand, passion fruit processing in China is relatively new, and most products are simple juice processing, with limited diversification in passion fruit-based foods; on the other hand, the peel and seeds of passion fruit are rich in nutrients but are often treated as waste after juice processing, leading to resource wastage. In response to the issues faced by passion fruit, several considerations can be made: First, passion fruit possesses significant product development potential.

This resource should be fully utilized to continuously optimize passion fruit processing techniques, enhance the comprehensive utilization of passion fruit, and maximize the retention of its nutritional components and flavor during processing to improve resource utilization efficiency; Second, in addition to fresh consumption, passion fruit can be developed into functional health foods tailored to the nutritional needs of different populations based on its rich nutritional profile, functional health foods tailored to the needs of different populations, thereby expanding the scope of passion fruit product development; Third, the passion fruit industry should strengthen guidance and regulation, encourage investment in research on comprehensive utilization of passion fruit, establish industry standards for passion fruit products, and promote the sustainable development of the passion fruit industry.

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