Yogurt Enrichment with Grape Pomace: Effect of Grape Cultivar on Physicochemical, Microbiological and Sensory Properties

Grape skin flours obtained from grape pomace of Chardonnay, Moscato and Pinot noir varieties were used as sources of polyphenolic compounds in yogurt formulation during three weeks of storage. Yogurt containing grape skin flour presented significantly higher total phenolic content (+55%), antioxidant activity (+80%) and acidity (+25%) whereas lower pH, syneresis (-10%) and fat (-20%) than control. Procyanidin B1 and vanillic acids were detected only in the yogurt added of Pinot noir flour while gallic acid, catechin and quercitrin were the major phenolic compounds found in the yogurts with Moscato or Chardonnay grape skins. Significant differences were highlighted for acidity and lactose content while total phenolic content, antioxidant activity and lactic acid bacteria trend were stable after production and storage. The liking test performed with consumers showed a loss of textural quality for yogurts fortified with grape skin flours.