Maristela Satou Martins

Levels of benzo [a] pyrene and other polycyclic aromatic hydrocarbons in liquid smoke flavour and some smoked foods

In order to investigate the levels of the polycyclic aromatic hydrocarbons, mainly benzo[a]pyrene because of its carcinogenicity, 55 samples of smoke flavour and smoked foods were analysed. The samples tested included 11 samples of liquid smoke flavour and 44 samples of smoked foods like bacon, loin, turkey, sausage, ox rib, etc. from different brands. A liquid chromatographic method was developed using a fluorescence detector. Benzo[a]pyrene was found in 73% of the liquid smoke flavour samples analysed. The levels varied from 0.1 to 336.6 micrograms/kg. Three liquid smoke flavour samples showed levels of benzo[a]pyrene above the maximum level recommended by FAO/WHO (10 micrograms/kg). From the total of 44 smoked food samples analysed, benzo(a)pyrene was detected in 23 samples (52%). The levels varied from 0.1 to 5.9 micrograms/kg. Anthracene and fluoranthene, non-carcinogenic polycyclic aromatic hydrocarbons, were found in almost all the samples analysed. Benzo[ghi]perylene, 3,4-benzofluoranthene and 1,2,3,4-dibenzopyrene were not found in any of the 55 samples analysed.

Sistematic study of benzo[a]pyrene in coffee samples

A method for extracting and quantifying benzo[a]pyrene (B[a]P) was evaluated and improved for samples of green and roasted ground Arabica (Coffea arabica) and Conillon (Coffea canephora) Brazilian coffees. The influence of the roasting process in B[a]P formation was considered too. These samples were extracted with acetone, followed by saponification and cyclohexane extraction. The extracts were cleaned by chromatography on a silica-gel. The quantification was done by HPLC with reversed-phase and fluorescence detection under isocratic conditions. The detection and quantification limits were 0.03 µg kg-1 and 0.10 µg kg-1, respectively. The recovery ranged from 76 to 116% for concentrations between 1.00 and 3.00 µg kg-1. The values obtained for B[a]P concentrations were from 0.47 to 12.5 µg kg-1 for samples of ground roasted coffee. B[a]P was absent in the green coffee samples. The control of the roasting parameters is fundamental for obtaining a good quality product.

Influence of distillation time and sample mass on sulfur dioxide analysis in passion fruit juice through Monier-Williams method.

This study aimed to evaluate the effect of the distillation time and the sample mass on the total SO2 content in integral passion fruit juice (Passiflora sp). For the SO2 analysis, a modified version of the Monier-Williams method was used. In this experiment, the distillation time and the sample mass were reduced to half of the values proposed in the original method. The analyses were performed in triplicate for each distilling time x sample mass binomial, making a total of 12 tests, which were performed on the same day. The significance of the effects of the different distillation times and sample mass were evaluated by applying one-factor analysis of variance (ANOVA). For a 95% confidence limit, it was found that the proposed amendments to the distillation time, sample mass, and the interaction between distilling time x sample mass were not significant (p > 0.05) in determining the SO2 content in passion fruit juice. In view of the results that were obtained it was concluded that for integral passion fruit juice it was possible to reduce the distillation time and the sample mass in determining the SO2 content by the Monier-Williams method without affecting the result.