DETERMINATION OF MINERAL COMPOSITION IN CV. TERAN (VITIS VINIFERA L.) RED WINE AFFECTED BY PRE-FERMENTATIVE MASH COOLING, HEATING, SAIGNÉE TECHNIQUE AND PROLONGED POST-FERMENTATIVE MACERATIONS

Abstract

This study aimed to determine mineral composition in red wine obtained from cv. Teran (Vitis vinifera L.), autochtonous Croatian grape variety. Six different vinification treatments, including the control treatment (7-day standard maceration), were performed to study the effects of: 48-hour pre-fermentative mash cooling (8 °C) followed by prolonged post-fermentative maceration of 13 days (C15), 28 days (C30), and saignée technique (juice runoff) proceeded with prolonged post-fermentative maceration of 13 days (CS15); and effect of 48-hour heating (50 °C) followed by prolonged post-fermentative maceration of 13 days (H15) and 28 days (H30) on macro- and microelements in wine. Respectively, macerations durated 15 and 30 days in total, including either pre-fermentative cooling or heating. Macro- (K, Ca, Mg, Na) and microelements (Al, Cu, Fe, Mn) were determined using the Optima DV 2000 inductively coupled plasma – optical emission spectrometer (Perkin Elmer, Shelton, Connecticut, USA) equipped with a Meinhard spray chamber, nebulizer, and peristaltic sample delivery system. The analysed elements were identified in line with ICP-OES using the PerkinElmer’s WinLab 1.35 software and quantified by direct calibration method. One-way analysis of variance (ANOVA) and Fisher’s least significance difference (LSD) test were used to compare mean values (p < 0.05). Statistics were performed using Statistica 10.0. software (Sta-Soft Inc. Tulsa, OK). The obtained results showed that the total content of macroelements in investigated wine ranged from 939.03 to 1038.57 mgL-¹. The total content of microelements ranged from 3.09 to 6.37 mgL-1, where was found that significantly the highest were treatments submitted to pre-fermentative heating (H15 and H30), despite duration of prolonged maceration. The most abundant minerals in investigated wine were potassium (K) among macroelements and iron (Fe) among microelements. The significantly highest concentration of iron (Fe) was found in the treatment equally affected with both pre-fermentative heating and prolonged post-fermentative maceration (H30). On the other hand, among the macroelements, the highest concentration of calcium (Ca) was found in treatments subjected to pre-fermentative heating (H15 and H30) regardless of maceration duration. Obtained results suggested that Teran red wine, affected with particular vinification processes considered as strong source of several micro- and macroelements.