Interactive effect of post-harvest processing method, roasting degree, and brewing method on coffee metabolite profiles

Our study aims to characterize metabolite profiles, varying by major determinants in brewed coffee as follows: three post-harvest processing, three roasting degrees, and two brewing methods for C. arabicacv. Geisha. The major discriminant factor was the roasting degree, explaining 58.84% of the total variance of metabolite profiles. Despite a lesser degree of influence, specific metabolite profiles were retained in temperature-based brewing (Light, 11.11%; Medium, 12.01%; Dark, 22.15%) and post-harvest processing (Light, 35.29%; Medium, 29.64%; Dark, 22.03%), respectively. The effect of pressure application on the coffee metabolome was significant only for the light roasted beans (9.88%). Of note, the post-harvest processing method was featured by norharman (anaerobic), pimelic acid (natural), and xanthine (washed). In addition, our study proposed novel compounds, DiHOMEs, associated with potential health benefits, which will step-up the coffee values and suggest future direction of the development of coffee processing.

Impact of different post-harvest processing methods on the chemical compositions of peony root

The impact of key processing steps such as boiling, peeling, drying and storing on chemical compositions and morphologic features of the produced peony root was investigated in detail by applying 15 processing methods to fresh roots of Paeonia lactiflora and then monitoring contents of eight main components, as well as internal root color. The results showed that low temperature (4 °C) storage of fresh roots for approximately 1 month after harvest resulted in slightly increased and stable content of paeoniflorin, which might be due to suppression of enzymatic degradation. This storage also prevented roots from discoloring, facilitating production of favorable bright color roots. Boiling process triggered decomposition of polygalloylglucoses, thereby leading to a significant increase in contents of pentagalloylglucose and gallic acid. Peeling process resulted in a decrease of albiflorin and catechin contents. As a result, an optimized and practicable processing method ensuring high contents of the main active components in the produced root was developed.