Analysis of free amino acids in green coffee beans

Abstract This work reports on monoamines (MA), diamines (DA) and polyamines (PA) as well as free amino acids (fAA) in nutritional supplements and infusions derived from green coffee beans. Samples were investigated using a ultra-high performance liquid chromatography UV/FLR method, which was validated regarding specificity, linearity, range, precision, accuracy and limits of detection and quantification. Nutritional supplements based on green coffee beans showed large amounts of total amines ranging from 1090 to 2593 mg/kg, with exceptional high levels of spermidine up to 724 mg/kg, and a content of fAA from 4004 to 12,389 mg/kg. Infusions brewed from green coffee beans showed much lower contents of amines (14–17 mg/L) and fAA (78–100 mg/L). However, if the customary edible portion was considered, infusions from green coffee were a mainly better source for MA and PA as well for fAA, compared to nutritional supplements. Tryptamine and tyramine were predominant as MA putrescine as DA, and spermidine as PA, respectively. Graphic abstract

Download Full-text

Analysis of free amino acids in green coffee beans

European Food Research and Technology ◽

10.1007/bf01231078 ◽

1996 ◽

Vol 203 (4) ◽

pp. 379-384 ◽

Cited By ~ 14

Author(s):

Ulrike Arnold ◽

Eberhard Ludwig

Keyword(s):

Amino Acids ◽

Free Amino Acids ◽

Free Amino ◽

Green Coffee ◽

Green Coffee Beans ◽

Coffee Beans

Download Full-text

Comparison of Batch and Continuous Wet-Processing of Coffee: Changes in the Main Compounds in Beans, By-Products and Wastewater

Foods ◽

10.3390/foods9081135 ◽

2020 ◽

Vol 9 (8) ◽

pp. 1135 ◽

Cited By ~ 1

Author(s):

Gustavo A. Figueroa Campos ◽

Sorel Tchewonpi Sagu ◽

Pedro Saravia Celis ◽

Harshadrai M. Rawel

Keyword(s):

Organic Acids ◽

Protein Content ◽

Free Amino ◽

Nutrient Content ◽

Coffee Bean ◽

Green Coffee ◽

Continuous Processing ◽

Green Coffee Beans ◽

Coffee Beans ◽

By Products

Many technical challenges still need to be overcome to improve the quality of the green coffee beans. In this work, the wet Arabica coffee processing in batch and continuous modus were investigated. Coffee beans samples as well as by-products and wastewaters collected at different production steps were analyzed in terms of their content in total phenols, antioxidant capacity, caffeine content, organic acids, reducing sugars, free amino group and protein content. The results showed that 40% of caffeine was removed with pulp. Green coffee beans showed highest concentration of organic acids and sucrose (4.96 ± 0.25 and 5.07 ± 0.39 g/100 g DW for the batch and continuous processing). Batch green coffee beans contained higher amount of phenols. 5-caffeoylquinic Acid (5-CQA) was the main constituent (67.1 and 66.0% for the batch and continuous processing, respectively). Protein content was 15 and 13% in the green coffee bean in batch and continuous processing, respectively. A decrease of 50 to 64% for free amino groups during processing was observed resulting in final amounts of 0.8 to 1.4% in the processed beans. Finally, the batch processing still revealed by-products and wastewater with high nutrient content encouraging a better concept for valorization.

Download Full-text