1. Robusta honey coffee drying techniques and identification of changes in the bioactives and volatiles based on SPME-GCMS and E-Nose.
- Author
-
Aswathi, K. N., Shetiya, Hiral, Premachandaran, M. Shikku, Swasthika, P. Y., Yannam, Sudheer Kumar, and Murthy, Pushpa S.
- Subjects
COFFEE flavor & odor ,COFFEE brewing ,BIOACTIVE compounds ,LOW temperatures ,COFFEE processing ,COFFEE beans ,CHLOROGENIC acid - Abstract
This research focused on the impact of drying techniques on the physicochemical and aromatic profile of honey coffee, which involves simultaneous fermentation and drying of coffee beans. Sun drying (SN), low temperature and low humidity drying (LTLH), polyhouse/solar tunnel drying (SD), and shade drying (SH) were carried out. Insignificant effect on physical quality was recorded. Chemical characterization of the raw coffee revealed that the LTLH-dried beans had higher carbohydrates (15.53%), which affected the coffee aroma. The roasted coffee contained caffeine (2.86%) and chlorogenic acid (2.50%), the primary bioactive components, contributing to strength, astringency and bitterness. The coffee brews had improved chemical metabolites such as carbohydrates (16.06%), total polyphenols (6.36%), flavonoids (0.7%) and antioxidants (5.4%). Furthermore, PCA correlates a total variance of 99.2% on green coffee, 97.3% on roasted coffee and 99.8% on brew. SPME–GC–MS revealed 75 volatiles in the roasted coffee and 95 in the infusions. Individual value plot graphs were introduced to assess the effect of volatiles on drying modes. Pyrazines and ketones were key molecules contributing to roasted walnut notes with fruity, floral and honey undertones. E-Nose profiles excellently overlaid GCMS results. SIMCA represented a positive correlation between LTLH coffee and volatile compounds. Thus, the LTLH technique (45–50 °C and 30–40% RH) for honey coffee facilitated an appropriate fermentation of coffee beans thereby improving the overall quality which, in turn, leads to global attention for innovative coffee processing technologies. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF