Određivanje vinske kiseline u voćnim nektarima i sokovima primjenom tekućinske kromatografije visoke djelotvornosti

master's thesis

• Title (english): Determination of tartaric acid in fruit nectars and juices using high performance liquid chromatography
• Author: Barbara Hren
• Mentor: Suzana Inić (mentor)
• Committee member: Suzana Inić (predsjednik povjerenstva)
• Committee member: Jasna Jablan (član povjerenstva)
• Committee member: Ana-Marija Domijan (član povjerenstva)
• Granter: University of Zagreb; Faculty of Pharmacy and Biochemistry; (Department of analytical chemistry); Zagreb
• Defense date and country: 2020-09-17, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry; Analytic Chemistry

Abstract

Vinska kiselina ima široku primjenu u prehrambenoj i farmaceutskoj industriji. U prehrambenoj industriji se u obliku aditiva (E334) koristi kao regulator kiselosti. Ako se prekomjerno unosi u organizam, može biti štetna za ljudsko zdravlje. U ovom diplomskom radu određena je koncentracija vinske kiseline u komercijalnim uzorcima voćnih nektara i sokova primjenom tekućinske kromatografije visoke djelotvornosti (HPLC, Knauer, Berlin, Njemačka) uz UV/Vis detektor. Korišten je 50 mM fosfatni pufer pH =2,8 kao mobilna faza na koloni obrnute faze (LiChrospher RP-18, 125x4,6 mm, 5 μm, Merck, Darmstadt, Njemačka). Validacija metode ispitana je korištenjem standardnih otopina vinske kiseline u rasponu koncentracija od 0,1 g/L do 1,0 g/L. Metoda je bila linearna u ispitivanom području (R2 =0,9996). Ponovljivost metode iskazana kao relativna standardna devijacija (RSD) bila je ispod 2%, a srednja preciznost iskazana kao RSD bila je manja od 3%. Granica dokazivanja iznosila je 0,01 g/L, a granica određivanja 0,04 g/L što ukazuje na osjetljivost metode. Vinska kiselina nije detektirana u tri uzorka voćnih nektara, a u četiri uzorka koncentracija je bila u rasponu 0,57 – 3,04 g/L. Razina vinske kiseline u tri prirodna voćna soka bila je u rasponu 3,92 g/L – 4,70 g/L i u skladu je s europskim propisima o dopuštenom dnevnom unosu vinske kiseline. Iz dobivenih rezultata može se zaključiti da je potrebno pratiti količinu vinske kiseline u svim prehrambenim proizvodima kako se ne bi prekoračio dopušteni dnevni unos vinske kiseline.

Abstract (english)

Tartaric acid is widely used in food and pharmaceutical industry. In food industry is used as acidulant and added in products as additive (E334). Higher intake of tartaric acid can be harmful to human health. In this thesis, the concentration of tartaric acid was determined in samples of commercially available fruit nectars and juices by using high performance liquid chromatography (HPLC, Knauer, Berlin,Germany) with UV/Vis detector. It was used 50 mM phosphate buffer pH = 2,8 as mobile phase on reversed phase column (LiChrospher RP-18, 125x4,6 mm, 5 μm, Merck, Darmstadt, Germany). Validation of the method was tested with standard tartaric acid solutions in range of concentracions of 0,1 g/L to 1,0 g/L. Method was linear (R2 = 0,9996). The repeatability of the method expressed as relative standard deviation (RSD) was less then 2 %, and the intermediate precision expressed as RSD was less than 3%. The limit of detection was 0,01 g/L, and the limit of quantification was 0,04 g/L which indicates sensitivity of the method. Tartaric acid was not detected in three samples of fruit nectar, in four samples the concentration of tartaric acid ranged from 0,57 g/L to 3,04 g/L. Level of tartaric acid in three samples of natural fruit juices was in range from 3,92 g/L to 4,70 g/L according to the european regulations of the acceptable daily intake of tartaric acid. From the obtained results it can be concluded that it is important to monitor the concentration of tartaric acid in all food products in order not to exceed the allowable daily intake of tartaric acid.

• Keywords: vinska kiselina; voćni nektari; sokovi; tekućinska kromatografija visoke djelotvornosti; HPLC; validacija
• Keywords (english): Tartaric acid; fruit nectars; juices; high performance liquid chromatography; HPLC; validation
• Language: croatian
• URN:NBN: urn:nbn:hr:163:308734
• Study programme: Title: Pharmacy; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: magistar/magistra farmacije (magistar/magistra farmacije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2021-05-10 15:42:12