Determination of Sugar Content in Commercial Fruit Juices by Refractometric, Volumetric and Chromatographic Methods

Abstract

In this paper several approaches are discussed for the direct analysis of the main sugars in different fruit juices. Refractometry, thin layer chromatography, volumetric analysis and high performance liquid chromatography with refractive index detector were tested and the results compared, discussing the advantages and disadvantages of each of them. Whereas the first method gives generically indications on the whole content of sugar and it doesn't require any prior manipulation of the sample, thin layer chromatography is useful only for qualitative purpose, on the other hand the third method, after removal of interferences, makes possible the determination of the reducing and not reducing sugar, and the last one allows the qualitative and quantitative determination of the saccharides singularly. It's very important to have not only knowledge about the chemical analysis of carbohydrates and their physicochemical properties, but especially how the methods can be used in product development for benefit of the public.In the wide range of options for the determination of the mono and disaccharides in beverages, the approach selected must be robust, accurate, powerful and reproducible.

A Review of Optical Interferometry Techniques for Quantitative Determination of Optically Active Materials in a Solution

“…A number of prescribed analytical techniques have been employed such as Ultra-voilet visible (UV-vis) absorption spectroscopy [1,2], thin-layer chromatography (TLC) [3], infrared (IR) and Fourier transform infrared (FTIR) spectroscopy [4,5] and Raman spectroscopy [6,7]. However, optical techniques such as polarimetry [8,9], interferometry [10,11] and refractrometry [12] are commonly used in most of the practical applications for quantitative determination of OAMs due to their rapidity, noninvasiveness and non-destructive nature of their method of analysis.…”

Development of Green UV-Vis Method for Direct Determination of Total Sugars in the Aqueous Extract of Teff (Eragrostis tef (Zuccagni) Trotter) Grains and Other Cereals

“…Cereals essentially consist of high proportions of carbohydrates, most come from starch and lower proportions come from total sugars [ 8 ]. Carbohydrates are important food components affecting taste and nutrition and are the main source of energy in cereals [ 8 , 9 ]. Teff is a whole grain and superior to other cereals due to being naturally gluten free and is the dominant source of nutrients like carbohydrates, amino acids, minerals, dietary fibers, proteins, dietary polyphenols, starch, and vitamins [ 6 , 10 – 12 ].…”