Quantification of Morpholine in Peel and Pulp of Apples and Oranges by Gas Chromatography−Mass Spectrometry

Abstract

Morpholine salts of fatty acids have been used in wax coatings on the surfaces of fruit and vegetable commodities in China and the United States, etc. However, morpholine usage was prohibited in many other countries because of safety concerns. We optimized analytical methods to determine morpholine in the peel and pulp of fruits and vegetables by gas chromatography-mass spectrometry (GC-MS). This morpholine analysis method was applied to real samples of apples, citrus fruits, and vegetables from Korea, China, and the U.S. The method was validated using apple and citrus fruit peels and pulp. The method detection limit (MDL) was 1.3–3.3 µg/kg. The recovery rates of morpholine were 88.6–107.2% over a fortified level of 10–400 µg/kg. Intra-day and inter-day precisions were 1.4–9.4% and 1.5–2.8%, respectively. The morpholine concentrations were n.d. (not detected)–11.19 and n.d. (not detected)–12.82 µg/kg in apple and citrus peels, respectively. Morpholine was not detected in citrus or apple pulp samples or in vegetable samples.

Basic Fuchsin Dye as the First Fluorophore for Optical Sensing of Morpholine in Fruits Crust and Urine Samples

“…In the lower range, the LOD for MOR is 2.0 × 10 –9 mol L –1 (0.17 ng mL –1 ) and the LOQ is 6.66 × 10 –9 mol L –1 (0.567 ng mL –1 ). The data presented in Table compares the developed method to other techniques, such as gas chromatography-mass spectrometry (GC-MS), gas chromatography-tandem mass spectrometry (GC-MS/MS), ultraperformance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS), gas–liquid chromatography-thermal energy analysis (GLC-TEA), and liquid chromatography-tandem mass spectrometry (LC-MS/MS), which have been used for the assessment of MOR in fruit peel, pulp, and juice beverage samples. ,,,,− The significance of the proposed spectrofluorimetric technique stems not only from its novelty in determining MOR but also from its high sensitivity, fast response time, convenience, and ease of performance.…”

“…One component of the coating is a colorless secondary amine cyclic ether morpholine (MOR) . MOR has been used as a systemic fungicide and as an adhesive, and MOR salts of fatty acids are being utilized as an emulsifier for wax coating. , The wax coating, which is thinly and evenly applied to the surfaces of fruits and vegetables, now contains MOR. However, MOR use raises safety concerns.…”

High Pressure Liquid Chromatography Identification and Quantification of Morpholine Residual Content in Cobicistat After Derivatization

“…MPE residues was quantified in juice, peel and pulp of fruits like apple, citrus, orange, strawberries, grapes and soy nutraceuticals using GC-MS, [8][9][10] UPLC-MS [11] and LC-MS/MS. [12] Quantification of residues of MPE in ibuprofen using GC-MS was also reported.…”