Figure 4. FTIR spectra of powdered pepper products having brand and their label says that it is made of 100% ground pepper (G, L, J, I, and H), and standard ground pepper (STD-100)

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Adulterated Powdered White Pepper Products by Tapioca Flour Sold in Indonesian’s Online Market Investigated by Simple FTIR Analytical Method

Achmat Sarifudin, Enny Sholichah, Woro Setiaboma, Riyanti Ekafitri, Nok Afifah, Lia Ratnawati, Eko Ari Pudiyanto, Nana Sutisna Achyadi

Journal of Food and Nutrition Research. 2021, 9(6), 297-303 doi:10.12691/jfnr-9-6-5