Chemical Composition Analysis, Sensory, and Feasibility Study of Tree Peony Seed

Eight wild species in Sect. Moutan DC (tree peony) of the genus Paeonia grown in natural habitats and 1 cultivated specie were investigated to analyze their fatty acid and bioactive phenolic compound profiles. For fatty acid composition, P. ludlowii contained the lowest α-linolenic acid (27.68%) and P. jishanensis contained the highest (51.96 %) content of the 9 species. For phenolic compounds, P. qiui contained the highest resveratrol (2.12 mg/g), P. delavayi contained the highest β-gentiobiosylpaeoniflorin (26.23 mg/g), and P. ostii contained the highest paeoniflorin (23.66 mg/g). P. ostii was selected to perform a feasibility study because of its relatively high level of α-linolenic acid 46.53%, low in ω-6 to ω-3 ratio of 1:2, and high level of the preferred bioactive phenolic compounds l including paeoniflorin and resveratrol. Physical pressing and refining process were conducted to obtain P. ostii seed oil. It exhibited bland sensory attributes described as slight grassy, very slight nutty, no painty or fishy aroma and slight grassy, slight nutty flavor with a very slight throat catch. Tocol results reported high level in tree peony seed oil 223.5 ± 13.65 mg/100 g with γ-tocopherol 70.1 ± 2.14 mg/100 g, and γ-tocotrienol 149.6 ± 15.83 mg/g. Because of the high total tocol, γ-tocopherol and γ-tocotrienol levels, and tree peony seed oil exhibited better oxidation stability than flaxseed oil even with similar α-linolenic acid levels. In addition, high levels of γ-tocopherol and γ-tocotrienol can introduce therapeutic effects such as antiinflammation and antioxidation. Therefore, this study showed that tree peony seed oil has a great potential to be used in edible oil, nutraceutical supplement, and other health care products.