Investigation of applicability of UV-light emitting diodes (UV-LEDs) as an alternative technology in pasteurization of cold-pressed and newly formulated mixed beverage
Başlık:
Investigation of applicability of UV-light emitting diodes (UV-LEDs) as an alternative technology in pasteurization of cold-pressed and newly formulated mixed beverage
Yazar:
Baykuş, Gökçen, author.
Yazar Ek Girişi:
Fiziksel Tanımlama:
ix, 75 leaves: charts;+ 1 computer laser optical disc.
Özet:
The aims of this thesis were to evaluate the cold pressing technique for juice extraction and to evaluate whether the cold pressed mixed beverage can be pasteurized with ultraviolet light emitting diodes (UV-LEDs) using E. coli K12 as the target microorganism. Initially, the physical, chemical and optical properties of cold pressed juice (CPJ) were compared with juice extracted by centrifugal juicer (CDJ). The CPJ was then exposed to UV-LEDs simultaneously and sequentially and the microbial inactivation was evaluated. Besides, barrier technologies have been tried to increase the UV-LED inactivation effect. It has been found that the juice yield performance of the cold pressing technique is better than the centrifuge method. The total phenolic content of the CDJ and CPJ was 922 ± 0.01 mg GAE/L, and 867.25 ± 0.01 mg GAE/L, respectively. However, DPPH radical scavenging activity of both beverages were not significantly different. The use of UV-LEDs in simultaneous or sequential mode could not achieve a 5-log reduction in pertinent microorganism required as part of HACCP mandated by US Federal regulations for juice issued by the Food and Drug Administration (FDA). However, filtration and addition of ginger juice revealed that the inactivation efficiency of UV-LEDs increased in highly turbid juice reaching to 3.65 ± 0.218 log10 CFU/ml. In conclusion, this study showed that UV-LEDs used simultaneously at different wavelengths may have the potential to be used in turbid cold press juice pasteurization when combined with different barrier technologies.
Yazar Ek Girişi:
Tüzel Kişi Ek Girişi:
Tek Biçim Eser Adı:
Thesis (Master)--İzmir Institute of Technology:Food Engineering.
İzmir Institute of Technology: Food Engineering --Thesis (Master).
Elektronik Erişim:
Access to Electronic Versiyon