| Title: | Emission of volatile organic compounds and production of secondary organic aerosol from stir-frying spices |
| Author(s): | Liu T; Liu Q; Li Z; Huo L; Chan M; Li X; Zhou Z; Chan CK; |
| Address: | "School of Energy and Environment, City University of Hong Kong, Hong Kong, China. Division of Environment, Hong Kong University of Science and Technology, Hong Kong, China. Earth System Science Programme, The Chinese University of Hong Kong, Hong Kong, China. Institute of Atmospheric Environment Safety and Pollution Control, Jinan University, Guangzhou, China. Earth System Science Programme, The Chinese University of Hong Kong, Hong Kong, China; The Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Hong Kong, China. Institute of Atmospheric Environment Safety and Pollution Control, Jinan University, Guangzhou, China; Guangdong Provincial Engineering Research Center for On-line Source Apportionment System of Air Pollution, Guangzhou, China. School of Energy and Environment, City University of Hong Kong, Hong Kong, China. Electronic address: Chak.K.Chan@cityu.edu.hk" |
| DOI: | 10.1016/j.scitotenv.2017.05.147 |
| ISSN/ISBN: | 1879-1026 (Electronic) 0048-9697 (Linking) |
| Abstract: | "Cooking is an important source of volatile organic compounds (VOCs) and a potential source of secondary organic aerosol (SOA) both indoors and outdoors. In this study, VOC emissions from heating corn oil and stir-frying spices (i.e. garlic, ginger, myrcia and zanthoxylum piperitum (Sichuan pepper)) were characterized using an on-line membrane inlet vacuum ultraviolet single-photon ionization time-of-flight mass spectrometer (VUV-SPI-TOFMS). VOC emissions from heating corn oil were dominated by aldehydes, which were enhanced by factors of one order of magnitude when stir-frying spices. Stir-frying any of the spices studied generated large amounts of methylpyrrole (m/z 81). In addition, stir-frying garlic produced abundant dihydrohydroxymaltol (m/z 144) and diallyldisulfide (DADS) (m/z 146), while stir-frying ginger, myrcia and zanthoxylum piperitum produced abundant monoterpenes (m/z 136) and terpenoids (m/z 152, 154). SOA formed from emissions of stir-frying spices through reactions with excess ozone in a flow reactor as well as primary organic aerosol (POA) emissions were characterized using a scanning mobility particle sizer (SMPS) and a high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS). Stir-frying garlic and ginger generated similar POA concentrations to those from heating corn oil while stir-frying myrcia and zanthoxylum piperitum generated double the amount of emissions. No SOA was observed from stir-frying garlic and ginger. The rates of SOA production from stir-frying myrcia and zanthoxylum piperitum were 1.8mugmin(-1)g(spice)(-1) and 8.7mugmin(-1)g(spice)(-1), equivalent to 13.4% and 53.1% of their own POA emission rates, respectively. Therefore, the contribution of stir-frying spices to ambient organic aerosol levels is likely dominated by POA. The rates of total terpene emission from stir-frying myrcia and zanthoxylum piperitum were estimated to be 5.1mugmin(-1)g(spice)(-1) and 24.9mugmin(-1)g(spice)(-1), respectively. Our results suggest that stir-frying spices could be an important source of terpenes in indoor environments in Hong Kong, at least during cooking" |
| Keywords: | Cooking emissions Secondary organic aerosol Spices Terpenes Volatile organic compounds; |
| Notes: | "PubMed-not-MEDLINELiu, Tengyu Liu, Qianyun Li, Zijun Huo, Lei Chan, ManNin Li, Xue Zhou, Zhen Chan, Chak K eng Netherlands 2017/05/26 Sci Total Environ. 2017 Dec 1; 599-600:1614-1621. doi: 10.1016/j.scitotenv.2017.05.147. Epub 2017 May 19" |
