Influence of Bean Processing Techniques on The Milling Process in Nano-Coffee Production
Annisa Aurora Kartika1, Noor Asnida Asli2 Eddie Ti Tjih Tan3 Mohamad Rusop2 Tunjung Mahatmanto1 Wenny Bekti Sunarharum1*

1Department of Food Science and Biotechnology, Faculty of Agricultural Technology, Universitas Brawijaya, Jalan Veteran Malang, 65145, Indonesia
2Centre for Functional Materials and Nanotechnology, Institute of Science, Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia
3Food Technology Department, Universiti Teknologi MARA, Cawangan Negeri Sembilan, Kampus Kuala Pilah, 72000 Kuala Pilah, Negeri Sembilan, Malaysia

*Corresponding author email: wbsunarharum[at]ub.ac.id

Abstract

Coffee, a crucial economic commodity, includes varieties like Liberica, valued for its climate resilience despite being less favored than Arabica and Robusta. Innovations in nanotechnology hold promise for enhancing coffee quality through nano-sized particles that elevate flavor, aroma, and nutrient availability. This study aimed to evaluate the impact of unfermented and lactic yeast fermentation processing techniques on the milling process and nanoparticle quality in Liberica nano-coffee production. Liberica coffee from Banyuwangi, Indonesia, was processed using two methods: unfermented and lactic yeast fermentation. After cleaning, sun-drying, and medium-level roasting, beans were milled at 500 rpm for 60, 120, and 180 minutes using ball milling, followed by sonication. Particles were analyzed using particle size analysis (PSA), field emission scanning electron microscopy (FESEM), and Fourier transform infrared spectroscopy (FT-IR). The study found that lactic yeast fermentation facilitated the production of smaller, more uniform nanoparticles due to microbial-induced structural changes in the beans. The nanoparticles from fermented beans were consistently smaller, averaging around 100-200 nm, compared to 300-400 nm for unfermented beans. FESEM analysis revealed a more homogenous particle distribution and smoother surface morphology in fermented beans. These findings suggest fermentation techniques improve nanoparticle quality in nano-coffee, advancing production practices in the coffee industry.

Keywords: Liberica coffee, Nanotechnology, Nano coffee production, Lactic yeast fermentation

Topic: Coffee agroforestry, science and technology