Iturmendi Vizcay, Nerea

Loading...
Profile Picture

Email Address

Birth Date

Job Title

Last Name

Iturmendi Vizcay

First Name

Nerea

person.page.departamento

Agronomía, Biotecnología y Alimentación

person.page.instituteName

IS-FOOD. Research Institute on Innovation & Sustainable Development in Food Chain

person.page.observainves

person.page.upna

Name

Search Results

Now showing 1 - 2 of 2
  • PublicationOpen Access
    Physical, chemical and microbiological changes in liquid micellar casein concentrates induced by high-pressure treatments
    (Elseiver, 2022) García Amezketa, Arantza; Iturmendi Vizcay, Nerea; Galarza Iriarte, Uxue; Maté Caballero, Juan Ignacio; Fernández García, Teresa; Agronomía, Biotecnología y Alimentación; Agronomia, Bioteknologia eta Elikadura; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
    Microfiltration and diafiltration were conducted to obtain 3 distinct levels of liquid micellar casein concentrates from raw skim milk: 8, 10 and 11.5 g casein/100 g. All the concentrates were subjected to 300, 450 and 600 MPa for 5 min. The physicochemical and microbiological changes in the matrix were studied and compared with their untreated counterparts on the day of production and after storing the samples for 7 d at 10 °C. Slight changes in pH were correlated with pressurization; the higher the pressure the greater the decrease in pH. For the least concentrated sample, changes were more noticeable. Furthermore, changes in particle size mainly occurred as a consequence of pressurization but also depended on casein concentration: aggregation and disruption phenomena were observed in the most concentrated samples. In terms of microbial quality, 600 MPa was the only treatment capable of achieving effective microbial control.
  • PublicationOpen Access
    Morphometry and textural surface properties of heat induced whey protein microparticles
    (Elsevier, 2025-09-01) Angós Iturgaiz, Ignacio; Vele, Lenin; Espinosa Rábanos, Isabel; Iturmendi Vizcay, Nerea; Fernández García, Teresa; Maté Caballero, Juan Ignacio; Agronomía, Biotecnología y Alimentación; Agronomia, Bioteknologia eta Elikadura; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
    The present work focuses on the study of four key factors controlling the process of whey protein microparticulation: protein suspension concentration (%WPI 2.5 % vs. 5.0 %); medium acidity (pH 4.5 vs. 5.5); denaturation temperature (80◦C vs. 90◦C); and particle size reduction method (180 bar x 1, 2 or 3 cycle(s); 1800 bar x 1 cycle). The effects of the microparticulation process were studied by analysing the degree of protein aggregation, morphometry, and surface textural characteristics of the microparticles. The results obtained indicate that the most favourable treatments to achieve a higher proportion of particles within the optimal range required by the food industry (1–10 μm) can be obtained by gentle protein denaturation (80◦C) using a medium with a pH lower than the isoelectric point of β-lactoglobulin and moderate concentrations of whey protein (2.5–5.0 %). Under these premises, it is necessary to use a high intensity particle size reduction method (1800 bar) to achieve the average diameter and the adequate homogeneity in a consistent fashion.