Functional compounds of Torreya grandis nuts and their processing byproducts: Extraction process, health benefits, and food applications - A comprehensive review

Torreya grandis (TG) nuts are highly valued for their rich content of bioactive compounds including lipids, proteins, carbohydrates, phenolic compounds, vitamins, and minerals, credited with numerous health benefits. In addition to their use in various culinary applications, such as baked goods and snacks, TG nuts are valuable source of high-quality oil rich in omega-3 and omega-6 unsaturated fatty acids, which has been shown to have anti-obesity, neuroprotective, and anti-diabetes effects. Besides, the byproducts from TG nuts processing, like the fruit aril and oil cake, are valuable sources of essential oils and proteins, respectively, with notable antioxidant, antimicrobial, and antifungal properties. Despite their nutrient profile and health promoting effects, TG nuts and their processing byproducts have received limited attention, hindering their wider use in food and medicinal applications. This review aims to bring attention to TG nuts by highlighting their nutritional and health benefits, and exploring their potential novel applications in the food sector. Research gaps were outlined to guide future research and products development. TG nuts hold great potential as functional foods and their byproducts like the aril could be repurposed for essential oil extraction, suitable for application in food flavoring and antimicrobial packaging. However, broader application of TG nuts and their byproducts in the food industry remain limited, and research regarding their nutrients profile is not comprehensive. Additionally, the bioactive compounds linked to their health benefits have not been properly identified, highlighting the need for further studies to explore their full potential.