Viscoelastic properties of orange fiber enriched yogurt as a function of fiber dose, size and thermal treatment

• Published in: Food science & technology Vol. 43; no. 4; pp. 708 - 714
• Main Authors: Sendra, E., Kuri, V., Fernández-López, J., Sayas-Barberá, E., Navarro, C., Pérez-Alvarez, J.A.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-05-2010; Elsevier
• Subjects: Biological and medical sciences; Citrus fiber; dietary fiber; fermentation; food fortification; Food industries; fortified foods; frozen yogurt; Fruit and vegetable industries; Fundamental and applied biological sciences. Psychology; Low fat dairy; low fat dairy products; Milk and cheese industries. Ice creams; orange pulp; oranges; particle size; pasteurization; plant fibers; rheological properties; Rheology; viscoelasticity; viscosity; Yogurt; Citrus fiber; Yogurt; Low fat dairy; Rheology; Heat treatment; Fruit; Citrus fruit; Size; Rutaceae; Dairy product; Orange; Low fat product; Citrus; Dicotyledones; Angiospermae; Spermatophyta; Milk fat; Rheological properties
• ISSN: 0023-6438; 1096-1127
• DOI: 10.1016/j.lwt.2009.12.005

The effect of orange fiber addition on yogurt viscoelastic properties was studied, the following factors were evaluated: (i) fiber doses (0, 0.2, 0.4, 0.6, 0.8 and 1
g/100
ml) (ii) fiber particle size (0.417–0.7 and 0.701–0.991
mm) (iii) fiber addition prior or after pasteurization. (i) In yogurts with pasteurized fiber
G′,
G″ and complex viscosity increased with fiber dose, whereas in non-pasteurized fiber yogurts smaller fiber particles (<0.4
g/100
ml) rheological parameters decreased due to the disruptive effect of the fiber, and over 0.6
g/100
ml rheological parameters increased. The presence of particles alters yogurt structure but when the fiber dose is high enough the water absorption compensates the weakening effect of the fiber. (ii)
G′,
G″ and viscosity were higher in yogurts with large particles than in yogurts with fiber of smaller size. The higher the number of fiber particles, the higher the disrupting effect. (iii) Fiber pasteurization in the mix enhances its integration in the gel matrix.