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Industrial treatments of commercial honeys during extraction and storage affect the quality of honey. One of the most common treatments in the honey industry is thermal treatment which could make some changes in the physicochemical and antioxidant properties of honey. This study was conducted to determine the effect of thermal treatment at 63 °C for 10, 20 and 30 min on physicochemical and antioxidant properties of lotus, thyme, and multifloral honeys. Samples were analyzed for pH, free acidity, moisture, hydroxymethylfurfural (HMF), color, total phenolic content, DPPH° radical-scavenging activity and ferric reducing antioxidant power (FRAP). Changes were more or less observed in all the physicochemical characteristics of honeys during the thermal treatment. However, among the physicochemical characteristics, increase in HMF content and decrease in total phenolic contents were more evident. Considering the antioxidant capacity of honeys, decreases in DPPH° radical scavenging activity of thyme honeys and FRAP values of thyme and lotus honeys during the thermal treatment were observed. Changes made in physicochemical characteristics of honeys during the thermal treatment are merely important from the standpoint of compliance with national and international legal limits. However, from the nutritional point of view, decrease in the antioxidant capacity of honeys is of particular importance and may affect the nutritional and health benefits of honey.

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Background: Nitrites are mainly used in food preservation. These materials could change to nitrosamine due to the effect of heat and gastric acid. Nitrosamine is absorbed in intestine and enters the liver and hepatocytes by portal venous system, and hampers the detoxification system of liver by interfering in cytochrome P450 enzymes, so, the liver gently proceeds to cirrhosis and cancer. Objectives: The current study aimed to investigate the hepatic and renal protective effects of aerial parts of Echinacea purpurea extract (EPE) on injury induced by diethylnitrosamine (DEN). Materials and Methods: Twenty Wistar rats were divided into 4 groups. Groups were as follow: Control group (normal saline), DEN (200 mg/ kg, IP, a single dose), EPE (100 mg/kg, orally, daily) and DEN + EPE which received as group DEN and EPE. After 30 days, Blood samples, and liver and kidney tissues were taken for further examination. Aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), BUN, Creatinine and total and direct bilirubin were estimated in serum. Results: DEN induced hepatotoxicity and nephrotoxicity in all the treated animals by elevated serum ALT, AST, ALP and BUN, creatinin and total and direct bilirubin levels. AST, BUN and total and direct bilirubin significantly decreased in DEN + EPE compared to DEN group. After 30 days of DEN administration, histopathological investigation revealed proliferation of hepatic stellate cells and early fibrosis which were partly improved by EPE administration. Conclusions: The current study findings indicated that Echinacea purpurea extract played an important role in the protection against DEN toxicity in rats.

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Background Despite having a lot of information about the physicochemical and antioxidant properties of honeys from different geographical regions, there is only limited information about the changes in these characteristics during long-term storage of honey. Hence, this study was conducted to evaluate these changes in five different types of honey, including alfalfa, milkvetch, lotus, thyme, and multifloral honeys, during one year of storage at room temperature.MethodsSamples were analyzed for pH, free acidity, Ash, moisture, electrical conductivity, hydroxymethylfurfural, color, total phenolic content, DPPH radical-scavenging activity and ferric reducing antioxidant power.ResultsChanges were more or less observed in all the physicochemical characteristics of honeys during the storage period. However, these changes did not exceed the maximum acceptable limits and after one-year of storage, the physicochemical properties of all types of honeys were within the standard limits except for HMF content in multifloral honey (43.89 mg/kg). Regarding the antioxidant capacity of honeys, our results showed 38.92-73.3 % decrease in DPPH radical scavenging activities and 43.29-67.0 % decrease in FRAP values of different types of honeys during  the storage period.ConclusionFrom the nutritional point of view, decrease in the antioxidant capacity of honeys is of particular importance. Therefore, these levels of reduction in antioxidant capacity could certainly affect the nutritional and health benefits of honey.

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Investigation were carried out to compare the efficiency of three plant essential oils; Zataria multiflora, Carum carvi and Mentha piperita as natural food preservatives. The effect of these plant essential oils at concentrations of 0.0, 0.3, 0.6 and 1% was studied against inoculated Escherichia coli O157:H7 (10(5) cfu mL(-1)) in prepared commercial chicken soup stored at 8 and 35 degrees C over seven (168 h) and three (72 h) days, respectively by plate count technique on CT-SMAC agar. Zataria multiflora was the most effective essential oil against the bacterium in all concentrations, followed by Mentha piperita and Carum carvi. The maximum inhibitory effects of all essential oils were seen at 1% concentration. The inhibitory effects were affected by the incubation temperature as well as by the type and concentrations of essential oils. The 1% concentration of Mentha piperita and 0.6 and 1% concentrations of Zataria multiflora essential oil showed bacteriostatic effect on growth of Escherichia coli O157:H7 at 35 degrees C. Also 1% concentration of Carum carvi, 0.6 and 1% concentrations of Mentha piperita and 0.6% concentration of Zataria multiflora essential oil had bacteriostatic effect while 1% concentration of Zataria multiflora essential oil showed bactericidal effect on the bacteria during the incubation period at 8 degrees C. It is concluded that selected plant essential oils have promising inhibitory effects on Escherichia coli O157:H7 in chicken soup and could be considered as natural food preservatives. This is especially relevant at a time when there is an increasing interest in finding more natural alternatives to many existing preservatives.