Annisa Aurora Kartika, Wenny Bekti Sunarharum, Noor Asnida Asli, Eddie Ti Tjih Tan, Mohamad Rusop, Tunjung Mahatmanto, Yuniar Ponco Prananto, Durratun Nasihah Mohd Shuhairi, Nur Syazwani Abdul Malek
Coffee is an essential economic commodity, with varieties such as Liberica recognized for their resilience to diverse climates, although it is less popular than Arabica and Robusta. However, its potential remains underutilized, especially in advanced food technology applications. Advances in nanotechnology offer potential improvements in coffee quality by utilizing nano-sized particles to enhance flavor, aroma, and nutrient bioavailability. This study investigates the effects of yeast-lactic acid fermentation processing techniques on the milling process and nanoparticle characteristics in the production of Liberica nano-coffee. Liberica coffee sourced from Banyuwangi, Indonesia, underwent yeast-lactic acid fermentation. After cleaning, sun-drying, and medium-level roasting, the beans were subjected to ball milling at 500 rpm for 60, 120, and 180 min, followed by sonication. The resulting coffee powder was analyzed using Particle Size Analyzer (PSA), Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared Spectroscopy (FT-IR), pH and color measurement, and IC50 assessments. PSA results indicate that lactic yeast fermentation led to smaller, more uniform nanoparticles. Physicochemical analysis showed a decrease in pH in fermented (F) coffee (5.07-5.13) compared to non-fermented (NF) coffee (5.45-5.50). Fermentation also resulted in darker coloration and a reduction in antioxidant capacity as indicated by higher IC50 values for F coffee compared to NF coffee, along with alterations in chromatic parameters. The milling process resulted in approximately 10% of the coffee particles being in the nanoscale for both NF and F coffee samples. FESEM revealed rougher surfaces in the milled F coffee sample, with enhanced porosity and flake-like structures. FTIR spectra confirmed biochemical alterations in F coffee, particularly in lipid degradation, organic acid accumulation, and polyphenol breakdown. This study presents a novel focus on Liberica coffee, an underexplored species in nanotechnology applications. The combination of fermentation and nanomilling demonstrates potential in enhancing antioxidant-related properties, positioning Liberica nano-coffee as a functional ingredient. © 2026, Walailak University. All rights reserved.
Department of Food Science and Biotechnology, Faculty of Agricultural Technology, Universitas Brawijaya, Jawa Timur, 65145, Indonesia; Centre for Functional Materials and Nanotechnology, Institute of Science, Universiti Teknologi MARA, Selangor, 40450, Malaysia; Food Technology Department, Universiti Teknologi MARA, Cawangan Negeri Sembilan, Kampus Kuala Pilah, Negeri Sembilan, 72000, Malaysia; Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Brawijaya, Jawa Timur, 65145, Indonesia