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A rapid and simple method for the simultaneous determination of twelve sweeteners and nine preservatives in various foods by liquid chromatography-tandem mass spectrometry LC-MS/MS was developed. The sweeteners and preservatives were extracted from solid samples with 80 and 50 methanol and from liquid samples with 80 methanol, followed by Oasis WAX cartridge cleanup. The LC separation was performed on a XSelect CSH Phenyl-Hexyl column 5 μm, 2.1 mm ×150 mm with a mobile phase of 10 mmol/L acetate buffer pH 4.0 -acetonitrile and MS detection with negative ion electrospray ionization. The quantification limits of acesulfame K AK , alitame AL , aspartame ASP , cyclamic acid CYC , neotame NEO , saccharin Na SAC , p-hydroxybenzoic acid methyl PHBA-Me , p-hydroxybenzoic acid ethyl PHBA-Et , p-hydroxybenzoic acid isopropyl PHBA-iPr , p-hydroxybenzoic acid propyl PHBA-Pr , p-hydroxybenzoic acid isobutyl PHBA-iBu and p-hydroxybenzoic acid butyl PHBA-Bu were 0.001 g/kg, those of dulcin DU , glycyrrhizic acid GLY , neohesperidin dihydrochalcone NHDC rebaudioside A REB , stevioside STV , sucralose SUC and benzoic acid BA were 0.005 g/kg, and those of sorbic acid SOA and dehydroacetic acid DHA were 0.02 g/kg. The mean recoveries from ten kinds of foods fortified at the levels of 0.02 and 0.2 g/kg were 70.9-119.0 , and their relative standard deviations were 0.1-11.7 .

No abstract

For the purpose of finding antioxidative spices, periodical POV changes of lard containing each of 27 different types of ground spices were quantitatively determined by the modified Lea method and compared with those of lard containing commercially obtained antioxidants.Most of herb spices gave fairly strong antioxidative effect on oxidation of lard, whereas, many spicy spices and seed spices showed no significant antioxidative effect except clove, ginger and mace. Sage, rosemary and mace showed very strong antioxidative effect being almost equivalent to that of BHA at a concentration of 0.1%. The antioxidative effect of thyme, clove or marjoram was considered to be equivalent to that of BHA at a concentration of 0.02%. Oregano and ginger showed stronger antioxidative effect than that of mixed tocopherols at a concentration of 0.1%.With the results obtained, 8 spices, namely, sage, rosemary, mace, thyme, clove, marjoram, oregano and ginger, were the strong antioxidative spices.

A method for the determination of nonvolatile amines (putrescine, cadaverine, histamine, tyramine and spermidine) in foods by solid-phase extraction and excimer-forming derivatization was investigated. Nonvolatile amines in a solid sample were extracted with 3 trichloroacetic acid, and the amines in a liquid sample were extracted with water. The extract was applied to polymer-based strong cation exchange mini-column, which was then rinsed with phosphate bu#er of pH 6.8 and water. Nonvolatile amines were eluted with 100 mmol/L potassium carbonate solution. The solution was mixed with 6 mmol/L 1-pyrenebutylyl chloride solution and derivatized. Derivatives of nonvolatile amines were analyzed by LC-FLD, and the identity of the amines was confirmed by LC-MS/MS without derivatization. The limit of detection (S/Nΐ3) of nonvolatile amines in all samples was 0.04 ῌg/g, and the limit of quantitation (S/Nΐ10) was 0.1 ῌg/ g. Recoveries of nonvolatile amines from fish tissues, miso, shoyu and red wine were in the range of 80.4ῌ111.