Analysis of Multi-Mycotoxins in Commonly Consumed Spices Using the LC-MS/MS Method for Assessing Food Safety Risks.

Mycotoxins are secondary metabolites produced by certain fungal species. In this study, the aim was to investigate mycotoxins, which pose a serious health problem. For this purpose, a total of 140 spice samples (black pepper, red pepper, cumin, and turmeric) purchased from Ankara, Turkey, were analyzed for specific mycotoxins (aflatoxin B1-AFB1, aflatoxin B2-AFB2, aflatoxin G1-AFG1, aflatoxin G2-AFG2, ochratoxin A-OTA, zearalenone-ZEN) using an LC-MS/MS multi-mycotoxin method. The Staphylococcus spp. and Micrococcus spp. counts in the spice samples were also analyzed using the conventional culture method. The contamination levels of AFB1 ranged from not detected (ND) to 39.12 µg/kg; AFB2 ranged from ND to 2.10 µg/kg; AFG1 ranged from ND to 0.92 µg/kg; AFG2 ranged from ND to 3.67 µg/kg; OTA ranged from ND to 39.79 µg/kg; ZEN ranged from ND to 11.16 µg/kg. The maximum residue limit for AFB1 (5 µg/kg) determined according to the Turkish Food Codex (TFC) was exceeded in five samples of red pepper, two samples of black pepper, and one sample of turmeric. Furthermore, it was determined that three samples of red pepper and one sample of black pepper exceeded the maximum limits for total aflatoxin (10 µg/kg) and OTA (15 µg/kg) specified in the TFC.

Room-temperature phosphorescence determination of melamine in dairy products using l-cysteine-capped Mn-doped zinc sulfide (ZnS) quantum dots.

A simple, sensitive, and precise room-temperature phosphorescence method was developed for the determination of melamine in dairy products using l-cysteine-capped Mn-doped zinc sulfide (ZnS) quantum dots as a probe. This method is based on the quenching of the phosphorescence signal of quantum dots by the interaction with melamine. Under optimum conditions, phosphorescence intensity was quenched by various concentrations of melamine in a linear range from 50 to 500ng/mL, with a detection limit of 5.95ng/mL in 10 mM phosphate buffer (pH 7.4). The relative standard deviation for 5 replicate measurements was 0.15%. The developed method was applied to dairy products to determine melamine concentrations; recovery values ranged from 96.3 to 104.7%.

Monosodium glutamate in chicken and beef stock cubes using high-performance liquid chromatography.

In this survey monosodium glutamate (MSG) levels in chicken and beef stock cube samples were determined. A total number of 122 stock cube samples (from brands A, B, C, D) were collected from local markets in Ankara, Turkey. High-performance liquid chromatography with diode array detection (HPLC-DAD) was used for quantitative MSG determination. Mean MSG levels (±SE) in samples of A, B, C and D brands were 14.6 ± 0.2 g kg⁻¹, 11.9 ± 0.3 g kg⁻¹, 9.7 ± 0.1 g kg⁻¹ and 7.2 ± 0.1 g kg⁻¹, respectively. Differences between mean levels of brands were significant. Also, mean levels of chicken stock cube samples were lower than in beef stock cubes. Maximum limits for MSG in stock cubes are not specified in the Turkish Food Codex (TFC). Generally the limit for MSG in foods (except some foods) is established as 10 g kg⁻¹ (individually or in combination).