Impact of Nonthermal Treatments on Quantity and Bioaccessibility of Phenolic Compounds in Food Matrix

Novel emerging nonthermal techniques that are alternatives to the traditional heat treatments are topical for a long time in food industry. Phenolic compounds are bioactive compounds have several health promoting effects and have been reported to exhibit antioxidative, anticarcinogenic, anti-inflammatory, antiaggregatory and vasodilating effects. Bioaccessibility, which is defined as the relative amounts of nutrients or phytochemicals released from a complex food matrix in the lumen of the gastrointestinal tract and therefore available for absorption into the body, is the first step for bioavailability. Nonthermal treatments affect the amount of phenolic compounds and bioaccessibility of phenolic compounds in food matrix. There are limited studies investigating effects of nonthermal treatments on quantity and especially bioaccessibility of phenolic compounds. Studies showed that HPP increased bioaccessibility of total flavonoids and some phenolic compounds such as hesperidin, rutin, etc. HPP generally increased bioaccessibility of phenolics, but there also some studies that HPP did not change or decreased bioaccessibility of phenolics. Ultrasound mostly increased bioaccessibility of phenolic compounds, excluding one study that bioaccessibility of phenolic compounds did not change. PEF and HIPEF have different impacts on bioaccessibility of phenolics depending on process conditions and food matrix. As nonthermal treatments can induce significant changes in food structure, it can influence the bioaccessibility of phenolic compounds that are intracellularly located. Consequently, bioaccessibility of phenolic compounds is highly dependent on composition of food matrix, food structure, type of nonthermal technique, processing conditions. This study aims to review the effects of nonthermal treatments such as HPP, ultrasound, PEF, HIPEF and HVED on both the amount and bioaccessibility of phenolic compounds in different food matrices.