DBPapers
DOI: 10.5593/sgem2017H/63/S25.037

NUTRITIONAL AND PHYSICOCHEMICAL ASPECTS OF FRESH AND COMMERCIAL FRUIT JUICES

A. Cozma, L. Micula, F. Radu, D. Lalescu, M. Petcu
Thursday 23 November 2017 by Libadmin2017

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgemviennagreen.org, SGEM2017 Vienna GREEN Conference Proceedings, ISBN 978-619-7408-29-4 / ISSN 1314-2704, 27 - 29 November, 2017, Vol. 17, Issue 63, 287-294 pp; DOI: 10.5593/sgem2017H/63/S25.037

ABSTRACT

Fruit juices are consumed worldwide, not only for their flavour, taste, and freshness, but also due to their beneficial health effects when are consumed regularly. Being relevant sources of vitamins, minerals and polyphenolic compounds many people are becoming aware of the importance of consuming them in their daily diet. The citrus juices, lemon, lime and grapefruit juice is the most appreciated and used because of its flavour and high content of vitamin C. The purpose of this study was to analyze and compare some physicochemical characteristics: pH, electrical conductivity, density, viscosity and total soluble solids content (TSS) in case of fresh fruit juice and the same assortment of pasteurized juice from the market. The pH was measured using a pH meter mark OP-211/2 connected with combined electrode OP-0808P according to the AOAC methods, total soluble solids and the refractive index were obtained using the refractometry method. Electrical conductance was determined by conductometer OK 112 and for the dynamic viscosity was used the Ostwald type viscometer. In case of analyzed juice samples, from obtained data we can see the highest difference is between natural grapefruit (3.39) and pasteurized grapefruit juice (2.98) from the market. So, juice from the supermarket has higher acidity than the natural fresh juice. Also, the viscosity for fresh juice has higher values then the viscosity for pasteurized juice, at the same kind of fruits. The data were statistically processed using Statistica10. The purpose of the statistical analysis was to highlight the correlations between the analyzed parameters expressed by a linear functional dependence between them. Study and analysis of the main physicochemical properties play an important role in the investigation of the fruit juice quality.

Keywords: fresh citrus juice, physical-chemical characteristics, pasteurized juice