No abstract

The results indicate that the MRPs derived from Arg and His under certain reaction conditions significantly prevent enzymatic browning in actual food systems. The intermediate compounds capable of preventing enzymatic browning are reductones and dehydroreductones, as confirmed by liquid chromatographic-mass spectrometric analyses.

The aim of the study was to investigate the changes in olive oils obtained from Edremit yaglık cultivar during malaxation. For this purpose, olives were processed to olive oil in industrial scale, and during processing olive paste obtained after crushing were malaxed for eight different malaxation times. The olive oil samples were evaluated for their quality parameters, volatile compounds, fatty acid, and sterol profiles. Results showed that free fatty acids increased; peroxide values, chlorophyll and carotenoid content, hexanal concentration decreased; K232 and K270 values, total phenol and tocopherol content fluctuated throughout malaxation. Fatty acid and sterol composition remained unchanged toward kneading process. Polyphenoloxidase activity decreased to a limit and remained almost constant till the end of malaxation period; whereas peroxidase activity tended to increase up to 40 min malaxation and afterward it began to lose its activity. PCA enabled the grouping of samples obtained from long and shorter malaxing periods. Practical applications Change in quality and some compositional parameters of virgin olive oil from Edremit yaglık variety during malaxation were investigated. Results have shown that some properties of virgin olive oil are affected by malaxation time. It is also possible to regulate the volatile composition by changing the kneading time. The current work examines the relation between the enzymatic activity and oil quality throughout the process, as well. The findings of the current study might be considered useful for olive oil producers to obtain optimum quality olive oil.

The aim of the present work was to evaluate the effect of rosemary extract (Rosmarinus Officinalis L.) on the 3-MCPD and glycidyl ester contents during deep-fat frying. Firstly, the potato samples were soaked in different concentrations of NaCl and they were fried in sunflower oils containing different concentrations of rosemary extract. Subsequently, repeated frying was carried out with sunflower oil enriched with rosemary extract. The frying oil and the oil extracted from potato samples were analyzed in terms of the contents of 3-MCPD and glycidyl esters according to DGF C VI 18 (10) method. The results demonstrated that the content of 3-MCPD and glycidyl esters in frying oil was not significantly affected by different NaCl and rosemary extract concentrations during short term frying; however, the amount of 3-MCPD esters was found to be lower for the potato crisps enriched with rosemary extract during repeated frying cycles. RESUMEN: Efecto de extractos de romero sobre 3-MCPD y ésteres de glicidol durante frituras. El objetivo del presente trabajo fue evaluar el efecto del extracto de romero (Rosmarinus Officinalis L.) sobre los contenidos de 3-MCPD y ésteres de glicidol durante la fritura. En primer lugar, muestras de patatas se remojaron en diferentes concentraciones de NaCl y se frieron en aceites de girasol que contienen diferentes concentraciones de extracto de romero. Posteriormente, se realizaron frituras repetidas con aceite de girasol enriquecido con extracto de romero. El aceite de fritura y el aceite extraído de las muestras de patatas se analizaron en términos de los contenidos de 3-MCPD y ésteres de glicidol de acuerdo con el método DGF C VI 18. Los resultados demostraron que el contenido de 3-MCPD y ésteres de glicidol en el aceite de fritura no se vieron afectados significativamente por las diferentes concentraciones de NaCl a corto plazo, sin embargo, la cantidad de ésteres de 3-MCPD fue menor para las patatas fritas enriquecidas con extracto de romero durante los ciclos de fritura repetidas. PALABRAS CLAVE: 3-MCPD ésteres; Aceite de girasol; Ésteres de glicidol; Extracto de romero; FrituraORCID ID: Yıldırım A https://orcid.org/0000-0001-5898-1209, Yorulmaz A https://orcid.org/0000-0003-4446-6585 Citation/Cómo citar este artículo: Yıldırım A, Yorulmaz A. 2018. The effect of rosemary extract on 3-MCPD and glycidyl esters during frying. Grasas Aceites 69 (4), e273. https://doi.

The objective of the current study was to assess the influence of a modified crushing process and kneading operation on the quality parameters, volatile compounds, and the fatty acid and sterol profiles of virgin olive oil from the Edremit yaglik variety. In the study, olive oil samples were produced in two different processes. The first one was produced without malaxation and the second one was produced with the malaxing process. During crushing, the effect of different temperatures was tested. The results demonstrate that different crushing temperatures generally did not affect the amount of free fatty acids, or peroxide value. Total phenol contents were positively affected by the additional malaxation process. Fatty acids and sterol composition were not significantly altered at different crushing temperatures or during the subsequent malaxation application. PCA enabled a clear classification of the oils obtained from different processing techniques.