The application of film based on gelatin/hydroxymethyl cellulose and red beetroot betalain in smart food packaging.

Edible films containing anthocyanin and betacyanin as indicators of freshness are promising systems for food smart packaging. This research aimed to develop a smart color film for food packaging using gelatin/hydroxypropylmethyl cellulose (HPMC) and red beet betalain. In this study, edible films with different ratios of gelatin to HPMC were prepared successfully, and the ratio of 3:1 was determined as optimal samples based on water vapor permeability (WVP) and mechanical properties. Betalain with different concentrations was then added to the optimal film, and the physical and mechanical properties of the resulting films were evaluated. Also, TVB-N test to assess their ability to detect beef meat and shrimp spoilage was studied. The addition of betalain improved the solubility, WVP, mechanical properties, and 2,2-diphenyl-l-picrylhydrazyl free radical scavenging activity of the film. As a final point, the incorporation of betalain into the gelatin/HPMC films can be used to indicate the freshness of food.

Diazinon reduction in food products: a comprehensive review of conventional and emerging processing methods.

Diazinon is known as one of the most commonly used organophosphorus pesticides which influence different pests through inactivating acetyl choline esterase enzymes. Despite diazinon applications, its toxicity to human health could result in a worldwide concern about its occurrence in foodstuffs. Malfunction of brain is considered as the main disorders induced by long time exposure to diazinon. Due to the degradation of diazinon in high temperatures and its susceptibility to oxidation as well as acidic and basic conditions, it could be degraded through several physical (9-94%) and chemical (19.3-100%) food processing procedures (both household and industrial methods). However, each of these methods has its advantages and disadvantages. Normally, the combination of these methods is more efficient in diazinon reduction. To this end, it is important to apply an effective method for diazinon reduction in the food products without affecting food quality or treating human health. It could be noticed that bioremediation by microorganisms such as probiotics could be a promising new method for diazinon's reduction in several food products.

Diazinon reduction in apple juice using probiotic bacteria during fermentation and storage under refrigeration.

The main objective of this work was to study the effects of probiotic strains, probiotic primary inoculated population, concentrations of spiked diazinon, physiology of probiotic bacteria, fermentation times, and cold storage period in six consecutive stages on diazinon reduction in apple juice. Chemical properties (pH, total acidity, and sugar content), probiotic viability, and diazinon reduction percent were monitored during fermentation and cold storage. Dispersive solid phase extraction (dSPE) followed by gas chromatography-mass spectrometry was used to extract and measure diazinon concentration. Results showed that Lactobacillus acidophilus revealed the highest ability to reduce diazinon in apple juice after fermentation. Inoculation of L. acidophilus at 9 log CFU/mL showed significantly higher diazinon reducing ability than 7 log CFU/mL. L. acidophilus reduced diazinon in apple juice samples containing 1000 µg/L of spiked diazinon significantly higher than those containing 5000 µg/L. Heat-killed (dead) L. acidophilus bacteria reduced less diazinon content at the end of fermentation than viable bacteria. Furthermore, 72 h of fermentation was more effective in diazinon reduction. Spiked diazinon is completely disappeared at the end of cold storage (28 days) in treatments containing L. acidophilus, while the viability of probiotic bacteria required for causing health-promoting properties was maintained in apple juice.

New method based on combining ultrasonic assisted miniaturized matrix solid-phase dispersion and homogeneous liquid-liquid extraction for the determination of some organochlorinated pesticides in fish.

In this study, ultrasonic assisted miniaturized matrix solid-phase dispersion (US-MMSPD) combined with homogeneous liquid-liquid extraction (HLLE) has been developed as a new method for the extraction of organochlorinated pesticides (OCPs) in fish prior to gas chromatography with electron capture detector (GC-ECD). In the proposed method, OCPs (heptachlor, aldrin, DDE, DDD, lindane and endrin) were first extracted from fish sample into acetonitrile by US-MMSPD procedure, and the extract was then used as consolute solvent in HLLE process. Optimal condition for US-MMSPD step was as follows: volume of acetonitrile, 1.5 mL; temperature of ultrasound, 40°C; time of ultrasound, 10 min. For HLLE step, optimal results were obtained at the following conditions: volume of chloroform, 35 µL; volume of aqueous phase, 1.5 mL; volume of double distilled water, 0.5 mL; time of centrifuge, 10 min. Under the optimum conditions, the enrichment factors for the studied compounds were obtained in the range of 185-240, and the overall recoveries were ranged from 39.1% to 81.5%. The limits of detection were 0.4-1.2 ng g(-1) and the relative standard deviations for 20 ng g(-1) of the OCPs, varied from 3.2% to 8% (n=4). Finally, the proposed method has been successfully applied to the analysis of the OCPs in real fish sample, and satisfactory results were obtained.