T. Altug

Degradation of aflatoxin B1 in dried figs by sodium bisulfite with or without heat, ultraviolet energy or hydrogen peroxide

Dried fig fruits were spiked to contain 250 ppb aflatoxin B1 (AFB1) and treated with sodium bisulfite (1% in the aqueous phase of the mixture). This treatment caused 28.2% of added toxin to degrade in 72 h at 25°C. When hydrogen peroxide (H2O2, 0.2% in the aqueous phase) was added 10 min before the bisulfite treatment, 65.5% of added toxin was degraded in 72 h. In both instances, most of the degradation occurred during the second day of treatment. Heating bisulfite-treated samples at 45 to 65°C for 1 h caused up to 68.4% of added AFB1 to be degraded. Ultraviolet radiation (from a low-energy source) degraded 45.7% of AFB1 in fig samples that were treated for 30 min; the rate of degradation was not enhanced when bisulfite or H2O2 was present during this treatment.

FLAVOUR CHARACTERIZATION OF SUMACH (Rhus coriaria L.) BY MEANS OF GC/MS AND SENSORY FLAVOUR PROFILE ANALYSIS TECHNIQUES

The flavour characteristics of sumach (Rhus coriaria L.) from the southeastern region of Turkey were investigated by using GC/MS and sensory flavour profile analysis techniques. Three different extraction methods for the isolation of volatiles were applied prior to GC/MS analysis. A total of 55, 17 and 28 volatiles were identified from the sumach sample by using liquid-liquid extraction, SC-CO2 extraction and distillation techniques, respectively. Malic acid was detected to be responsible for the sour taste of sumach. β-caryophyllene (spicy, woody), cembrene (woody) and caryophyllene oxide (spicy) which were detected by using the three different isolation techniques seem to have an important contribution to sumach flavour. Sensory flavour profile analysis revealed oil and acid aroma and dried lemon balm, cellulose/woody, spicy, earthy and astringent flavour characters as common descriptors in grinded sumach, SC-CO2 extract, and water extract of sumach samples examined in this study.

Descriptive Analysis of Red Wines From Different Grape Cultivars in Turkey

A total of 15 red wines produced from 8 grape varieties were evaluated and profiled by quantitative descriptive analysis. The results of wine aroma characteristics demonstrated the following major descriptors for each wine type: grape juice, flowery (Cinsaut), flowery, dust (Calkarası), raisin, wet wood (Boğazkere), raisin, caramel (Cabernet sauvignon), raisin, dust (Gamay), cornel cherry, pineapple (Syrah), caramel, grape juice (Kalecık karası), and medicinal, caramel (Karasakız). Flavor profile of red wines revealed specific flavor descriptors for each wine type, namely: sour cherry, medicinal, grape juice (Cinsaut), medicinal, hot wood, grape juice (Calkarası), raisin, cornel cherry, dry apricot (Boğazkere), raisin, medicinal, plum (Cabernet sauvignon), sour cherry, tobacco, raisin (Gamay), cornel cherry, grass, pineapple (Syrah), sour cherry, green, wood (Kalecik karası), and sour cherry, medicinal (Karasakız).

Descriptive Profiling of Flavor Attributes of White Wines From Different Grape Varieties

The aim of the present study was to determine the effect of using different grape varieties on the sensory flavor characteristics of Turkish white wines. 17 commercial white wines from 5 grape varieties (Emir-5, Narince-4, Semillon-4, Muscat-2, Chardonnay-2) of 2001 vintage, obtained from local market were analyzed by quantitative descriptive analysis. Graphical representation of the sensory profiles including aroma and flavor characteristics were provided as spider-web diagrams by plotting the mean values for the sensory descriptors. Least significant differences between wines for each descriptor were calculated by analysis of variance (ANOVA) using the SPSS program. It was observed that characteristics such as alcohol, sulphur, and raisin were present in the aroma and flavor of all wine varieties, while some characters seemed to be specific for wines produced from certain types of grapes (grape juice- Emir-1, 2, 3, 4; rose-Muscat-1,2; green plum-Semillon-1, 2; melon-Narince-3; banana- Chardonnay-1; tobacco- Chardonnay-2).

Quality Changes in Unsulfured Sun Dried Apricots During Storage

The sun dried apricots (Hacihaliloglu) from Malatya region of Turkey without sulfur dioxide application packaged in polyvinyl chloride laminated with polyethylene bags of different thickness under normal and modified atmosphere were stored at 5 ± 1, 15 ± 1, and 25 ± 1°C, respectively. The changes in quality characteristics of dried apricots were investigated by using objective and sensory methods of evaluation during a storage period of 48 weeks. The study showed that the unsulfured sun dried apricots have a storage life of up to 30 weeks provided that they are packaged under modified atmosphere and stored at 5 ± 1°C after processing.

Carry-Over of Aflatoxins to Fig Molasses from Contaminated Dried Figs

The carry-over of aflatoxins to fig molasses produced by using two different processing techniques from contaminated dried figs (> 1000 ppb of total aflatoxins) were examined by using a HPLC technique. The effects of extraction, bleaching and concentration steps on the reduction of aflatoxin levels were also investigated. The reductions in total aflatoxin levels in fig molasses produced by using the two techniques were detected to be 62 and 38%, respectively. Extraction, bleaching and concentration steps were observed to cause 22% reduction in total aflatoxin levels.