A chemometric approach to the evaluation of sparkling ciders produced by Champenoise and Charmat methods

Abstract

The production of sparkling cider could intercept the needs of non-habitual consumers of this alcoholic-beverage. This investigation was aimed to develop procedures for the production of sparkling ciders using the Italian apple variety ‘Limoncella’ by application of both Champenoise and Charmat methods.First of all, the authors apply a chemometric approach to evaluate the effects of duration of the pectolytic treatment carried out on crushed apples and of the sugar added before refermentation on physicochemical, and sensory characteristics of the Champenoise sparkling ciders. The pectolytic treatment was able to influence colour, alcohol, pH, bitterness (higher when the treatment was shorter), titratable and volatile acidity, soluble solids, CO2, total phenolics, sweetness, saltiness, bitterness, and volatile alcohols (higher when the treatment was longer). The addition of sugar increased alcohol, soluble solids, and CO2, and decreased the production of volatile compounds.Then, the effects of the refermentation methods (Champenoise or Charmat) on the same parameters were evaluated. Charmat and Champenoise sparkling ciders differed for parameters showing higher values in the second type, i.e. colour (9.982 and 14.296 SRM), organic acid concentrations, CO2 (6.35 and 7.55 g/L), phenolic (313 and 424 mg/L) and volatile content, foam persistence (2.2 and 3.8), and saltiness (2.1 and 3.2) –– and for some sensory attributes such as taste quality and harmony that received higher scores in Charmat sparkling ciders (4.9 ± 0.7 and 4.9 ± 0.0, respectively) than the Champenoise ciders (3.7 ± 0.5 and 3.7 ± 0.4, respectively). Several esters, alcohols, terpenes, acids, phenols, and norisoprenoids had odour activity values > 1. Principal Component Analysis (PCA) was able to homogeneously group Champenoise ciders based on the duration of the pectolytic treatment and the addition of sugar before fermentation. PCA was also able to distinguish sparkling ciders by refermentation methods.The results indicated that the chemometric approach is a sensitive tool to monitor the quality and authenticity of local sparkling cider productions. The reduction of the pectolytic treatment time was critical to avoid dramatic increases of lactic acid content. The Champenoise method preserved the cider phenolic content but negatively affected their sensory quality.