Detecting and Monitoring the Flavor of Tomato (Solanum lycopersicum) under the Impact of Postharvest Handlings by Physicochemical Parameters and Electronic Nose

Sai Xu; Xiuxiu Sun; Huazhong Lu; Hui Yang; Qingsong Ruan; Hao Huang; Minglin Chen

doi:10.3390/s18061847

Detecting and Monitoring the Flavor of Tomato (Solanum lycopersicum) under the Impact of Postharvest Handlings by Physicochemical Parameters and Electronic Nose

Sensors (Basel). 2018 Jun 6;18(6):1847. doi: 10.3390/s18061847.

Authors

Sai Xu^{1

2}, Xiuxiu Sun³, Huazhong Lu^{4

5}, Hui Yang⁶, Qingsong Ruan⁷, Hao Huang⁸, Minglin Chen⁹

Affiliations

¹ Public Monitoring Center for Agro-Product of Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China. xusai@gdaas.cn.
² College of Engineering, South China Agricultural University, Guangzhou 510640, China. xusai@gdaas.cn.
³ Indian River Research and Education Center, University of Florida, Ft. Pierce, FL 34845, USA. sunxiuxiu6@gmail.com.
⁴ Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China. huazlu@scau.edu.cn.
⁵ College of Engineering, South China Agricultural University, Guangzhou 510640, China. huazlu@scau.edu.cn.
⁶ Public Monitoring Center for Agro-Product of Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China. yanghui@gdaas.cn.
⁷ College of Engineering, South China Agricultural University, Guangzhou 510640, China. rqs171@stu.scau.edu.cn.
⁸ College of Engineering, South China Agricultural University, Guangzhou 510640, China. huanghao01@stu.scau.edu.cn.
⁹ College of Engineering, South China Agricultural University, Guangzhou 510640, China. chenminglin@stu.scau.edu.cn.

Abstract

The objective of this study was to detect and monitor the flavor of tomatoes, as impacted by different postharvest handlings, including chilling storage (CS) and blanching treatment (BT). CS tomatoes were stored in a refrigerator at 5 °C and tested at storage day 0, 3, and 7. BT tomatoes were dipped in 50 or 100 °C water for 1 min, and tested immediately. The taste, mouth feel, and aroma of tomatoes were evaluated by testing the total soluble solid content (TSS), titratable acidity (TA), ratio of TSS and TA (TSS/TA), firmness, and electronic nose (E-nose) response to tomatoes. The experimental results showed that the CS can prevent taste and firmness loss to a certain extent, but the sensory results indicated that CS accelerated flavor loss due to the TSS/TA of CS tomatoes increasing slower than control. The taste and firmness of tomatoes were impacted slightly by 50 °C BT, and were significantly impacted by 100 °C BT. Based on physicochemical parameters, different postharvest handling treatments for tomatoes could not be classified except for the 100 °C BT treated tomatoes, which were significantly impacted in terms of taste and mouth feel. The E-nose is an efficient way to detect differences in postharvest handling treatments for tomatoes, and indicated significant aroma changes for CS and BT treated tomato fruit. The classification of tomatoes after different postharvest handling treatments, based on comprehensive flavor (physicochemical parameters and E-nose combined data), is better than that based on single physicochemical parameters or E-nose, and the comprehensive flavor of 100 °C BT tomatoes changed the most. Even so, the tomato flavor change during postharvest handlings is suggested to be detected and monitored by single E-nose data. The E-nose has also been proved as a feasible way to predict the TSS and firmness of tomato fruit rather than TA or TSS/TA, during the postharvest handing process.

Keywords: electronic nose; flavor; impact; pattern recognition; physicochemical index; postharvest handling; tomato.

MeSH terms

Agriculture / methods*
Electronic Nose*
Food Analysis / instrumentation*
Food Analysis / methods*
Fruit / chemistry*
Odorants / analysis*
Solanum lycopersicum / chemistry*
Taste*