Industrial Yogurt Manufacture: Monitoring of Fermentation Process and Improvement of Final Product Quality

Profiles of pH and incubation during the lactic acid fermentation of whole and skim milk.

Viscosity-incubation time profiles during the lactic acid fermentation of A) whole and B) skim milk.

Correlations of incubation time (min) and viscosity (cPs×10⁻¹) with pH in yogurts prepared with A) whole and B) skim milk.

Effects of processing conditions (treatment at 80 or 95°C) and ingredients: xanthan, κ-carrageenan, pectin, guar gum, skim milk powder (SMP), whey powder (WP), and milk protein concentrate (MPC), on the incubation time of yogurts made with whole and skim milk.

Effects of processing conditions (treatment at 80 or 95°C) and ingredients: xanthan, κ-carrageenan, pectin, guar gum, skim milk powder (SMP), whey powder (WP), and milk protein concentrate (MPC), on the viscosity of yogurts made with whole and skim milk.

Effects of processing conditions (treatment at 80 or 95°C) and ingredients: xanthan, κ-carrageenan, pectin, guar gum, skim milk powder (SMP), whey powder (WP), and milk protein concentrate (MPC), on the acidity of yogurts made with whole and skim milk.

Effects of processing conditions (treatment at 80 or 95°C) and ingredients: xanthan, κ-carrageenan, pectin, guar gum, skim milk powder (SMP), whey powder (WP), and milk protein concentrate (MPC), on the acetaldehyde concentration of yogurts made with whole and skim milk.

Principal components analysis of yogurts (physicochemical properties). Key: noadd = no addition; xan = xanthan; car = carrageenan; pec = pectin; gua = guar gum; smp = skim milk powder; wp = whey powder; pc = milk protein concentrate; 80 and 95 = heat-treatment at 80°C and 95°C, respectively; S = skim milk; W = whole milk.

Principal components analysis of yogurts (selected sensory attributes). Key: noadd = no addition; xan = xanthan; car = carrageenan; pec = pectin; gua = guar gum; smp = skim milk powder; wp = whey powder; pc = milk protein concentrate; 95 = heat-treatment at 95°C; S = skim milk; W = whole milk.