Fermentation of cow milk and/or pea milk mixtures by different starter cultures: Physico-chemical and sensorial properties

• Five mixtures of cow milk and/or pea milk were fermented by 10 starter cultures.
• Fermentative behavior, syneresis, rheological and sensorial properties were studied.
• Pea protein reduced the rheological and sensorial quality of fermented milk.
• Two starter cultures showed negative sensory properties as astringency & bitterness.
• Four starter cultures did not show negative sensorial characteristics.

Five mixtures of milk and pea protein (0–40 g pea protein/100 g total protein) were fermented by ten starter cultures of lactic acid bacteria (LAB)2 to select the cocktails that can lead to products similar to a conventional yoghurt. Generally speaking, an increase in pea concentration leads to products with higher acidity, higher syneresis and lower firmness. From the sensory perspective, up to 30 g pea protein/100 g total protein, starter cultures show either positive or negative effects. A principal component analysis (PCA)3 and a hierarchical cluster analysis (HCA)4 carried out on all variables revealed five groups of products. Two groups of products of 0 g or 10 g pea protein/100 g total protein seemed to be the most similar to conventional dairy products. The third group included products fermented with two starters with negative characteristics such as astringency and bitterness. The last two groups included members made of 10 g, 20 g, 30 g and 40 g pea protein/100 g total protein, among them one group showing a positive sensory profile. From this group, four starter cultures seem promising for the fermentation of milk and pea protein mixtures.