Evaluation of quality parameters in liquid grape pekmez (Molasses) from different brands available in the market

Abstract

This study examined the physicochemical properties of industrial and traditionally produced pekmez samples available on the market and compared them with the Turkish Grape Pekmez Notification (2017/8) standards. Significant variability was observed in parameters such as °Brix, pH, ash content, HMF concentration, titratable acidity, water activity, and colour. °Brix values ranged from 69.03% to 80.73%, in consistent with Codex standards. One traditional sample had a pH of 4.76, placing classifying it as sour pekmez. Four industrially produced pekmez samples exceeded the 2.5% ash limit, but HMF concentrations varied widely, with one traditional sample surpassing the regulatory limit of 75 mg/kg limit. Titratable acidity ranged from 0.19% to 1.95%, and water activity values were between 0.59 and 0.74, indicating moderate to low water activity. Colour analysis revealed a spectrum from dark to lighter shades, with a shift from greenish to reddish hues, typical of grape pekmez. These findings underscore the impact of production methods on pekmez quality and variability.

Keywords

• Grape pekmez
• Molasses
• Codex
• Pekmez quality
• HMF

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