Impact of high intensity pulsed electric field on antioxidant properties and quality parameters of a fruit juice–soymilk beverage in chilled storage

• Published in: Food science & technology 2010-07, Vol.43 (6), p.872-881
• Main Authors: Morales-de la Peña, M., Salvia-Trujillo, L., Rojas-Graü, M.A., Martín-Belloso, O.
• Format: Article
• Language: English
• Subjects: Acidity; antioxidant activity; Antioxidant properties; antioxidants; ascorbic acid; bacterial contamination; beverages; Biological and medical sciences; blended foods; cold storage; electric field; enzyme activity; food contamination; Food industries; food nutrient losses; food preservation; food spoilage; food storage; free radical scavengers; Fruit and vegetable industries; fruit juices; Fruit juice–soymilk beverage; Fundamental and applied biological sciences. Psychology; High intensity pulsed electric field; lactic acid bacteria; Lactobacillus brevis; lipoxygenase; Listeria innocua; microbiological quality; molds (fungi); peroxidase; plate count; psychrotrophic bacteria; pulsed electric fields; Quality parameters; refrigeration; shelf life; soymilk; yeasts
• ISSN: 0023-6438; 1096-1127
• DOI: 10.1016/j.lwt.2010.01.015

The effects of high-intensity pulsed electric fields (HIPEF) treatment (35 kV/cm, 4 μs bipolar pulses at 200 Hz for 800 or 1400 μs) on the microbial stability, quality parameters and antioxidant properties of a fruit juice–soymilk (FJ–SM) beverage along the storage time at 4 °C were compared to those obtained by thermal pasteurization (90 °C, 60 s). HIPEF processing for 800 μs ensured the microbial stability of the beverage during 31 days; however, longer microbial shelf-life (56 days) was achieved by increasing the treatment time to 1400 μs or by applying a thermal treatment. Peroxidase and lipoxygenase of HIPEF treated beverages were inactivated by 17.5–29% and 34–39%, respectively; whereas thermal treatment achieved 100% and 51%. During the storage, vitamin C content and antioxidant capacity depleted with time, and they were higher in FJ–SM beverages processed by HIPEF than in those thermally treated. Instead, total phenolic content of beverages did not present significant changes over the time, and it was higher in the 1400 μs-HIPEF treated beverages. In general, color, soluble solids, pH, and acidity values were not significantly affected by the processing treatments. Beverage viscosity increased over time, regardless of the treatment applied. Hence, application of HIPEF may be a good alternative treatment to thermal processing in order to ensure microbiological stability, high nutritional values and fresh-like characteristics of FJ–SM beverages.