In this paper, the optimal extraction process of polyphenols from Chaenomeles sinensis (Thouin) koehne was studied by single factor test and response surface test. Research results showed that the optimum extraction conditions were as follows: enzymatic time 55 min, ethanol concentration 59%, enzymatic liquid-material ratio 28:1 mL/g, pectinase amount 20 μL/g, enzymatic pH 3.4, enzymatic temperature 65°C, ultrasonic liquid-material ratio 30:1 mL/g, ultrasonic time 40 min, ultrasonic temperature 55°C. Under these conditions, the extracted content of Chaenomeles sinensis (Thouin) koehne polyphenols was 62.07 mg/g.

Chestnut shell is one of the main by-products in the chestnut processing, which contains abundant polyphenols, so it can be used as a source of polyphenols. In this study, using ethanol as the extraction solvent, the optimum extraction conditions of polyphenols from chestnut shell were determined by single factor experiment and response surface experiment: liquid-solid ratio of 39:1, extraction temperature of 74°C, extraction time of 91 min, ethanol concentration of 65%. Under these conditions, the extraction rate (ER) of polyphenols from chestnut shell was 6.09%. The results can assist in better exploitation of chestnut shell, which can not only reduce resource waste and environmental pollution, but also obtain economic benefits.

Heat treatment was used to extend the shelf life of postharvest Chaenomeles speciosa (Sweet) Nakai (C. speciosa), its effects on the quality and physiological properties of C. speciosa were studied. The results showed that heat treatment reduced the weight loss, inhibited the decline of titratable acids (TA), maintained a higher activity of peroxidase (POD) and catalase (CAT), compared to untreated C. speciosa. Treatment in hot water dipping at 50℃ for 2-4 min maintained the better quality of postharvest C. speciosa stored at 0℃ for 120 days, which indicated that heat treatment is an effective preservation technology to prolong the shelf life of C. speciosa.