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Abstract

Minimal processing technologies, like High Hydrostatic Pressure (HHP), heat treatments at low temperatures have an increasing role in food industry. Eggs are considered as functional foods, but for high retention of biological active compounds adequate minimal processing technologies are needed during preservation procedure. In our study, liquid egg yolk (LEY) was examined to meet consumer's expectations.

Combinations of pasteurization (57–63 °C, 5–7 min) and HHP (350–400 MPa, 5 min) were used to provide microbiological stability of LEY. After these treatments samples were examined for mesophyll aerobes and Enterobacteriaceae cell counts (using Nutrient agar an incubation of 30 °C, 48 h) and viscosity attributes (Anton Paar MCR 92).

Our results show that microbiological stability is significantly influenced by the different parameters of heat treatments and HHP. Heat treatment effected at least 3 orders of magnitude decrease in cell count. Viscosity attributes point out that higher pressure of HHP have a stronger effect on viscosity than the temperature of pasteurization.

The results point out a great opportunity for industrial use of minimal processing technologies for LEY. Microbiological safety is strongly influenced by the order of treatments, but viscosity may be independent from the order of the treatments.

Open access
Progress in Agricultural Engineering Sciences
Authors: Karina Ilona Hidas, Csaba Németh, Anna Visy, Adrienn Tóth, László Ferenc Friedrich, and Ildikó Csilla Nyulas-Zeke

Abstract

Eggs are commonly used in the food industry because of their excellent nutrient value and also for their coagulating, foaming, emulsifying, colouring and flavouring properties. Manufacturers substitute shell eggs with processed egg products, such as liquid whole egg, liquid egg yolk or albumin. They have a shelf life of a few weeks, but freezing can increase it to 1 year. However, freezing causes gelation in case of egg yolk. This process is highly dependent on the conditions of freezing and thawing.

In our study, raw liquid egg yolk was frozen and stored for 14 days at −18 °C. On days 1, 7 and 14 samples were thawed by two different methods. Denaturation temperature and enthalpy were investigated by differential scanning calorimetry. Besides, rheological properties were examined at 20 °C, Herschel–Bulkley model was fitted to flow curves of the examined samples. The dry matter content was also recorded during the experiment. Two-way ANOVA was used to analyse data.

The results of the study showed that method of thawing had no significant effect on calorimetric and rheological properties and dry matter content. In contrast, freezing and frozen storage had a significant effect on denaturation enthalpy and rheological properties.

Open access
Progress in Agricultural Engineering Sciences
Authors: Karina Ilona Hidas, Csaba Németh, Lien Phuong Le Nguyen, Anna Visy, Adrienn Tóth, László Friedrich, and Ildikó Csilla Nyulas-Zeke

Abstract

Freezing can enhance the storage time of liquid egg products, but egg yolk undergoes an irreversible textural and structural change when it is cooled to –6 °C. In this study, the effects of different salt concentrations on the physical properties of frozen-thawed egg yolk were investigated.

The pasteurised liquid egg yolk (LEY) was treated with 4, 5, and 6% of NaCl before freezing and it was stored at –18 °C for 4 weeks. The colour, pH, and rheological characteristics (firmness, consistency, cohesiveness, and index of viscosity) of yolk samples were evaluated before and after freezing.

Salt treatment resulted in preventing gelation, with decreasing firmness, consistency and viscosity compared to control samples. The pH of all yolk samples increased during frozen storage. The lightness value decreased in treated samples and increased in the control sample after freezing.

The results indicated that the applied salt concentrations could inhibit protein aggregation of LEY induced by freezing during the storage period. At least 5% salt concentration could reduce effectively the changes in rheological properties.

Open access
Magyar Onkológia
Authors: Janina Kulka, Anna-Mária Tőkés, Adrienn Ildikó Tóth, Attila Marcell Szász, Andrea Farkas, Katalin Borka, Balázs Járay, Eszter Székely, Roland Istók, Gábor Lotz, Lilla Madaras, Anna Korompay, László Harsányi, Zsolt László, Zoltán Rusz, Béla Ákos Molnár, István Arthur Molnár, István Kenessey, Gyöngyvér Szentmártoni, Borbála Székely, and Magdolna Dank

A neoadjuváns kemoterápiára adott patológiai választ kívántuk elemezni az emlőtumorok immunhisztokémiai fenotípusai, valamint az alkalmazott kemoterápiás protokollok tükrében. 1998 és 2009 között 92 neoadjuváns kezelésen átesett emlőtumoros nőbeteg klinikai adatait, biopsziás és műtéti anyagát valamint túlélési mutatóit vizsgáltuk. A biopsziás- és műtéti anyagokon hormonreceptor (ER, PgR), Ki-67, p53, HER2 státusz meghatározás történt immunhisztokémiai módszerrel. A patológiai válasz megítélésére a Chevallier-osztályozást használtuk. 88 esetben elemeztük a betegségmentes- és a teljes túlélést a patológiai válasz függvényében. Patológiai komplett remisszió (pCR = Chevallier I és II) volt kimutatható 13/92 esetben (14,1%). A preoperatív daganatjellemzők alapján a patológiai komplett remissziót mutató daganatok a tripla negatív (9/13) valamint az ER-/HER2+ (1/13) és az ER+/HER2+ (3/13) csoportokból kerültek ki. 24 beteg részesült taxán-, 30 antraciklin-, 33 taxán+antraciklin alapú terápiában, 2 CMF típusú neoadjuváns kezelésben, 3 esetben nem állt rendelkezésünkre ez az adat. A taxánnal kezelt betegek 29,1%-ában, az antraciklin-származékkal kezelt betegek 6,6%-ában, a kombinált kezelésben részesült betegek 12,1%-ában volt kimutatható pCR. A pCR-t mutató csoportban kevesebb volt a recidíva és a távoli áttét kialakulása, de nem tudtunk szignifikáns különbséget igazolni. A kezelésre reagáló (Chevallier III) és a nem reagáló (Chevallier IV) csoport között ebben a tekintetben szignifikáns különbséget találtunk (p=0,006). A betegségspecifikus halálozás szignifikánsan alacsonyabb volt a pCR betegcsoportban (p=0,050). Eredményeink alapján a patológiai komplett remissziót mutató esetek a tripla negatív és a HER2-pozitív csoportból kerültek ki. A neoadjuváns kezelés az ER+/HER2- tumorcsoportban volt a legkevésbé hatékony.

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