Identification and dosage by HRGC of minor alcohols and esters in Brazilian sugar-cane spirit
ABSTRACT The presence of 51 volatile compounds, among alcohols and esters in Brazilian sugar-cane spirit (cachaça), were investigated by high-resolution gas chromatography (HRGC). The following alcohols and esters were identified and quantified: methanol, 1,4-butanodiol, 2-phenylethyl alcohol, amyl alcohol, cetyl alcohol, cynamic alcohol, n-decanol, geraniol, isoamyl alcohol, isobutanol, menthol, n-butanol, n-dodecanol, n-propanol, n-tetradecanol, amyl propionate, ethyl acetate, ethyl benzoate, ethyl heptanoate, isoamyl valerate, methyl propionate, propyl butyrate. The average higher alcohols content (262 mg/100 mL in anhydrous alcohol a.a.) and total esters content (24 mg/100 mL a.a.) in cachaças, are smaller than in other spirits. The average methanol content in cachaças (6 mg/100 mL a.a.) is the same as in rum, but smaller than in wine spirit. No qualitative differences of chemical profile among cachaças have been observed.
- Journal of the Brazilian Chemical Society 01/2014; DOI:10.5935/0103-5053.20140213 · 1.25 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: The traceability of the fermentative process during the production of Brazilian sugarcane spirits (cachaças) was investigated for different yeast strains of Saccharomyces cerevisiae. Two different distillation apparatus were used for this purpose: copper alembic stills and stainless steel columns. The data set (44 chemical compounds and 105 samples of sugarcane spirits) including products from column and alembic, treated with Principal Components Analysis showed that the concentrations of ethyl lactate, dimethyl sulfide and acetic acid are correlated with the natural fermentation process. For the samples distilled in stainless steel column, the first three principal components account for 77.7% of the total variance (PC1—54.9%; PC2—13.4%; PC3—10.3%). Linear discriminant analysis using as chemical descriptors ethyl hexanoate, ethyl dodecanoate, ethyl lactate, ethyl octanoate, ethyl decanoate, isoamyl octanoate, dimethyl sulfide, isobutyl alcohol and isoamyl alcohol provides a robust chemical model able to correctly classify 83% of the cachaças according to their respective fermentation process. A less clear classification (predictive ability of 42%) was observed for the sugarcane spirits distilled in the alembic stills.Journal of Food Composition and Analysis 03/2015; 38:98-105. DOI:10.1016/j.jfca.2014.11.001 · 2.26 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: This work presents a strategy for controlling acetaldehyde content in Brazilian bioethanol, based in simulation results of a typical industrial distillation plant. The major problem of acetaldehyde in bioethanol is that, during the storage period, it can oxidize to acetic acid, increasing fuel acidity above the legislation limit. This work tested, by dynamic simulation, simple loops to control acetaldehyde in bioethanol. The dynamic simulation generated a disturbance in the wine to be distilled by increasing acetaldehyde content, and verified how those loops were able to control the acetaldehyde level in bioethanol. Two different column system configurations were investigated. The first one includes a degassing system and a second one that produces pasteurized alcohol without or with a degassing system. Suggestions for the best control system of acetaldehyde contamination in bioethanol were formulated according to the acetaldehyde level in the wine.