Comparative studies between fumigation and irradiation of semi-dry date fruits

Physical properties and mass models of Deglet Noor and Arichti semi-dry Algerian date fruits: A comparative study

For thousands of years, date fruit (Phoenix dactylifera L.) has been a popular diet in arid and semi-arid locations. It has religious importance for Muslims and is especially important during the holy month of Ramadan. The global output of date fruits has been continuously expanding, with Arab nations accounting for a sizable portion. The emphasis of this research is on two popular semi-dry Algerian date fruit types, Deglet Noor and Arechti, which are grown in the Ziban region. These fruits' physical parameters, such as size, sphericity, surface area, volumes, and density, were determined. The goal of this study was to create a mass model based on these physical attributes to help in the grading and sorting of date fruits. Fruit mass was shown to be closely connected to linear dimensions, arithmetic and geometric mean diameters, surface area, and volumes. Correlations between mass and physical attributes were established using a variety of mathematical models, including linear, quadratic, S-curve, and power models. The results demonstrated the applicability of specific factors for mass modeling, offering useful insights for the development of system sizing and conservation. With good correlation, multivariate data analysis was employed to correctly estimate the mass of both kinds. This research advances our understanding of the physical features of Algerian date fruits and their connection to mass, allowing for better handling, sorting, and packing processes in the worldwide date market.

Bioactive coatings from nano-biopolymers/plant extract composites for complete protection from mycotoxigenic fungi in dates

BACKGROUND

Contamination of date fruit with mycotoxigenic fungi is a hazardous threat. The present study investigated the effectiveness of natural derivatives for controlling this. Chitosan (Cts) was produced from Aspergillus niger mycelia and characterized and then nanochitosan (NCt) particles were synthesized from fungal Cts. Edible-coating films were formulated based on Cts, NCt, pomegranate peel extract (PPE) and their composites and these were evaluated as antifungal materials against mycotoxigenic fungi, Aspergillus flavus, Aspergillus ochraceus and Fusarium moniliforme.

RESULTS

The Cts produced had 88.7% deacetylation, a molecular weight of 24.5 kDa and 98% solubility in diluted acetic acid, whereas the particle diameters of synthesized NCts ranged from 35 to 65 nm. The inhibition zone assay emphasized the antifungal effectiveness of the entire coating films. The most effective agent for preparing edible film was the blend of NCt + PPE followed by Cts + PPE based films. The practical application of antifungal films for date decontamination with respect to mycotoxigenic fungi demonstrates that the films were very effective for controlling the entire fungal strain and preventing growth on the fruits.

CONCLUSION

The NCt + PPE and Cts + PPE based films were found to be the most effective because they could completely eliminate the growth of any fungal spore on date fruit after 48 h from the coating experiment. © 2019 Society of Chemical Industry.

Microflora of date fruits and production of aflatoxins at various stages of maturation

Twenty-five varieties of dates (Phoenix dactylifera) were examined at different maturation stages for total microbial counts, aflatoxins and aflatoxigenic Aspergillus sp. and lactic acid bacteria. The samples were examined as fresh and under simulated storage condition of high humidity. Microbial counts were high at the first stage of maturation (Kimri) and increased sharply at the second stage (Rutab), then decrease significantly at the final dried stage of maturation (Tamr). Aflatoxins were detected in 12% of the samples although aflatoxigenic Aspergillus were detected in 40% of the varieties examined, all at Kimri stage only. Lactic acid bacteria were present only at the Rutab stage in some varieties including all varieties in which aflatoxins or aflatoxigenic Aspergillus were detected. No aflatoxins or aflatoxigenic Aspergillus were detected at the final edible stage of maturation.