Formaldehyde can be added illegally as a food preservative in addition to the endogenous formaldehyde that naturally occurs in aquatic products. In this study, formaldehyde was derivatized from 2,4-dinitrophenylhydrazine and analyzed using gas chromatography–mass spectrometry to investigate free and reversibly bound formaldehyde in 10 squid and squid products. The results were compared to those obtained by high-performance liquid chromatography (HPLC). The limit of detection was 2.0 mg/kg. The total concentrations of free and reversibly bound formaldehyde were, on average, higher than the free formaldehyde concentration by 26.6 mg/kg. Free formaldehyde made up, on average, 39% of total free and reversibly bound formaldehyde. The sum of the concentrations of free and reversibly bound formaldehyde was, on average, higher than the free formaldehyde concentration by 19.3 mg/kg in the HPLC method. Free formaldehyde made up an average of 39% of total free and reversibly bound formaldehyde in the HPLC method. The use of gas chromatography–mass spectrometry to detect formaldehyde in aquatic products allowed confirmation through retention time and molecular mass information. The monitoring of free formaldehyde in aquatic products and proper control of the manufacturing process could help to reduce the formaldehyde level in shredded squid products. Finally, exposure to formaldehyde from consumption of shredded squid was estimated: it was less than 0.2 mg/kg, which is the oral reference dose suggested by the US Environmental Protection Agency

Edible seaweed products have been consumed in many Asian countries. Edible seaweeds accumulate iodine from seawater, and are therefore a good dietary source of iodine. An adequate consumption of seaweed can eliminate iodine deficiency disorders, but excessive iodine intake is not good for health. The recommended dietary reference intake of 0.15 mg/d and 0.14 mg/d for iodine has been established in the United States and Taiwan, respectively. In this study, 30 samples of seaweed were surveyed for iodine content. The samples included 10 nori (Porphyra), 10 wakame (Undaria), and 10 kombu (Laminaria) products. The iodine in seaweed was derivatized with 3-pentanone and detected by gas chromatography-electron capture detector (GC-ECD). The method detection limit was 0.5 mg/kg. The iodine content surveyed for nori was 29.3–45.8 mg/kg, for wakame 93.9–185.1 mg/kg, and for kombu 241–4921 mg/kg. Kombu has the highest average iodine content 2523.5 mg/kg, followed by wakame (139.7 mg/kg) and nori (36.9 mg/kg). The GC-ECD method developed in this study is a low-cost alternative to inductively coupled plasma-optical emission spectroscopy for iodine detection in seaweeds. The iodine intake from seaweed in the current survey was calculated and compared with the iodine dietary reference intake of Taiwan. The risk and benefit of seaweed consumption is also discussed

The analytical method for sweeteners in various food matrixes is very important for food quality control and regulation enforcement. A simple and rapid method for the simultaneous determination of 10 sweeteners [acesulfame potassium (ACS-K), aspartame (ASP), cyclamate (CYC), dulcin (DUL), glycyrrhizic acid (GA), neotame (NEO), neohesperidin dihydrochalcone (NHDC), saccharin (SAC), sucralose (SCL), and stevioside (STV)] in various foods by liquid chromatography/tandem mass chromatography (LC-MS/MS) was developed. The chromatographic separation was performed on a Phenomenex Luna Phenyl-Hexyl (5 μm, 4.6 mm × 150 mm) column with gradient elution of 10 mM ammonium acetate in water and 10 mM ammonium acetate in methanol. The recoveries of the 10 sweeteners were between 75% and 120%, and the coefficients of variation were less than 20%. The limits of quantification were 0.5 μg/kg for NHDC and SCL. For the other sweeteners, the limits of quantification were 0.1 μg/kg. Compared to the traditional high-performance liquid chromatography method, the LC-MS/MS method could provide better sensitivity, higher throughput, enhanced specificity, and more sweeteners analyzed in a single run. The samples included 27 beverages (16 alcoholic and 11 nonalcoholic beverages) and 15 pickled foods (1 pickled pepper, 3 candies, and 11 candied fruits). Two remanufactured wines were found to contain 7.2, 8.5 μg/g SAC and 126.5, 123 μg/g CYC, respectively. ACS-K, ASP, SCL, and NEO were detected in five beverages and drinks. The pickled peppers and candied fruits were found to contain SAC, GA, CYC, ASP, STV, NEO, and ACS-K. The wine with sweeteners detected was remanufactured wine, not naturally fermented wine. Therefore, the ingredient label for the sweeteners of remanufactured wine should be regulated by the proper authority for inspection of sweeteners.