Physicochemical, sensory characterisation and volatile components of 16 NFC pear juice

Abstract

Pear (Pyrus spp.) has the function of clearing heat, reducing fire and moistening the lungs. Not from concentrated (NFC) pear juice can better maintain the nutrition, aroma and taste of pear fruit, which is worth considering as a pear processing product. Fruit raw materials play a key role in the preparation of NFC juice. In order to obtain suitable varieties for NFC pear juice, this study investigated the fruit quality of 16 kinds of pear from China, and the physicochemical characteristics, sensory quality and volatile components of NFC pear juice. The results revealed that there was a great difference among the species. The weight of single fruit varies from 84.03 to 334.96?g and juice yield from 39.39 to 85.22%. For the juice, L* values from 32.74 to 45.13, a* values from ??0.72 to 3.79%, b* values from 2.01 to 11.00. Browning degree from 0.66 to 4.35. Total soluble solids from 8.26 to 12.89%, sugar contents from 1.28 to 6.64%, total acidity from 0.65 to 7.55?g/L, and apparent viscosity from 2.42 to 3.99 mPa s. Total polyphenols from 32.35 to 116.48?mg/100mL, total flavonoid content from 21.14 to 372.32?mg/100mL. The DPPH radical scavenging ability from 60.77 to 96.28%, ABTS radical scavenging ability from 7.5 to 45.60%. 70 volatile components were detected in 16 NFC pear juices, mainly including alcohols, esters and aldehydes, etc. Overall sensory score from Anli (4.45) to Williams pear (7.72). Through correlation analysis and principal component analysis, it was found that the variety of pear fruit was an important factor affecting the quality of fruit juice.