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Both the dielectric constant and loss factor increased at a temperature that appeared to match the DSC denaturation temperature for collagen in beef, chicken breast, chicken thigh, perch, cod, and salmon. When the sample was reheated the change did not reoccur, indicating that the dielectric properties were measuring an irreversible change. At lower frequencies the increase in the dielectric properties was larger. When collagen and actomyosin denature, the muscle shrinks, expelling water and minerals. This makes the water and ions more mobile. The dielectric constant and loss factor measure the mobility of water and ions; therefore they may be able to determine the temperature of protein denaturation.

Increasing the concentration of salt (NaCl) or starch in a saltstarch solution depressed the dielectric constant and loss factor relative to a pure salt solution, except for the loss factor when no salt was present. The addition of salt to a starch solution increased the viscosity. Both viscosity and dielectric properties were decreased by mechanical agitation and by action of amylase. Above 10% starch the decrease in dielectric loss was abrupt, corresponding to the increase in viscosity. The changes were hypothesized to be due to an interaction between salt and starch, either through direct binding of the salt, or indirectly through the increase in viscosity.

Seventy-five samples of different spices marketed in Turkey were purchased from bazaars, herbal shops and supermarkets. Equal amounts of paprika, chilli, black peppers and cumin were purchased and used to test and compare the amount of aflatoxin contamination. Two different analytical methods were examined for their efficacy by adding a known amount of aflatoxin to the blank samples of paprika. Twenty-seven paprika, all the chilli powder and four ground black pepper samples were contaminated with aflatoxin B 1 in the range of 0.5-116.4, 1.6-80.4 and 0.3-1.2 lg kg )1 respectively. Twenty-three (30%) paprika and chilli powder samples were above the regulatory limits used in the European Union. No aflatoxin contamination was detected in the cumin samples at a detection limit of 0.2 lg kg )1 .

Sour (tart) cherry is an industrial fruit where a considerable amount of by-products remain after processing. Sour cherry by-products consist of pomace (skin and flesh) and seeds (pit, stone) which remain after the fruit juice and IQF processes. Sour cherry pomace is characterized with a high content of phenolic compounds and the seed constitutes a high oil yield with beneficial effects on human health because of their antioxidant, antimicrobial, and anti-inflammatory properties. There has been a great interest in sour cherry by-products due to the increasing production rate of sour cherry worldwide and the increasing efforts on seeking bioactive compounds from natural sources as functional food. Thus, there have been a number of studies regarding the sour cherry pomace and sour cherry seed, especially in the last five years. The present review summarizes the chemical, biological, functional, and technological properties of the sour cherry pomace and sour cherry seed with their current and potential applications.

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Changes in water and ion binding that occur during egg protein denaturation can be detected by measuring the dielectric properties. The dielectric properties of egg yolk, egg white and egg ovalbumin were tested from 25 to 105 degrees C at 11 frequencies from 300-2450 MHz. DSC was used to determine the temperature of protein denaturation. Both the dielectric constant and loss factor of egg yolk decreased due to denaturation of the protein lipovitellin. The dielectric constant increased at the initial denaturation and decreased after the complete denaturation and aggregation of egg ovalbumin in both egg white and ovalbumin.