© AUG 2019 | IRE Journals | Volume 3 Issue 2 | ISSN: 2456-8880 IRE 1701498 ICONIC RESEARCH AND ENGINEERING JOURNALS 176 Development of an HPLC Method For Determination of Some Preservatives in Soy Sauce NI NI WIN 1 , KHIN WIN AYE 2 , YI YI MYINT 3 1 Department of Engineering Chemistry, Technological University (Meiktila), Myanmar 2 Department of Engineering Chemistry, Pyay Technological University, Myanmar 3 Department of Research and Innovation, National Analytical Laboratory, Myanmar Abstract -- A simple, selective and precise reversed-phase high performance liquid chromatography (HPLC) method has been developed for the simultaneous quantification of benzoic acid (BA), methyl paraben (MP), and butyl paraben(BP) in soy sauce. The preservatives (BA, MP and BP) from soy sauce samples were extracted with a C18 bonded silica SPE cartridge. 10% methanol in 1% orthophosphoric acid solution followed by methanol was found to be the best solution for sample clean-up. The chromatographic separation of HPLC method was performed by using a PerkinElmer Brownlee Analytical DB C18 column (2.1 mm X 100 mm, 1.9 μm) and binary pump. The preservatives were eluted with methanol/NH4OAc buff-er and determined by a gradient elution system in one run (23 minutes) with UV detection at the maximum absorption wave-length, 230 nm for BA, and 254 nm for MP and BP. The average recoveries of benzoic acid, methyl paraben, and butyl paraben were 90, 93 and 100 %, respectively. The calibration curves showed good linearity over the concentration range of 1.0 - 60 μg/g. The regression coefficients were acceptable (R2 > 0.995). This SPE-HPLC method was proved to be a useful protocol for quantification of the preservative in soy sauce. Indexed Terms: Soy sauce; preservatives; benzoic acid; parabens; solid phase extraction (SPE); HPLC-UV I. INTRODUCTION Preservative is any substance used in the food preservation process that can act as agent to prevent any alteration either of taste and appearance of the food due to microorganism and to minimize the risk of toxic food. According to directive 95/2/EC dated on 20.02.1995, “the preservatives are substances that increase the food preservation time by protecting them against the damages caused by micro- organisms”[1]. Among the available commercial food preservatives, benzoic acid (BA) and its ester derivatives are widely used. Benzoic acid is one of the weak organic acid preservative agents that inhibits the growth of both bacterial and fungal cell [2,3]. The parabens are also possible to be used as anti-microbial agents to exert the intended affects against mold and yeasts. The parabens are considered safe antimicrobial agents with relatively non- irritating and non-sensitizing effects as well as low toxicity to the human [4]. It has been previously reported that the concentration of benzoic acid and sodium benzoate used as a food preservative was ranging up to 2000 mg kg -1 [3]. Excess amounts of these additives can be harmful to human health. Therefore, the minimum permissible concentrations of benzoic acid and the esters of p- hydroxybenzoic acid (parabens) are controlled by regulation, and the quantitative analysis of these preservatives is important in routine analysis of foods. Fruit juice and beverage can be directly analyzed without clean-up procedures prior to determine by HPLC [5,6], while the other food samples, such as cheese, sauce, jam, milk, yogurt and canned seafood by HPLC technique, requires sample pretreatment, which usually involved solvent extraction or precipitation of proteins and fats by the addition of methanol or acetonitrile followed by centrifugation[6,7]. Sweet soy sauce is become one of the favorite condiments and very often used as food flavor enhancer in Asian cuisine. The commercial sweet soy sauce contains some amount of preservatives to be stored for a longer time. Sodium benzoate and methyl paraben, are the two very common preservatives added in the commercial soy sauce. The maximum allowable amount of benzoic acid and parabens added in soy sauce are 600 mg kg -1 and 250 mg kg -1 , respectively [8]. In recent years, some analytical methods have been developed for the determination