Use of microwave processing to reduce the initial contamination by Alicyclobacillus acidoterrestris in a cream of asparagus and effect of the treatment on the lipid fraction

Synergistic cellulose-based nanocomposite packaging and cold plasma decontamination for extended saffron preservation

Sterilization of saffron packaging and maintaining the quality of saffron content are the main priorities in saffron preservation. Common modalities do not offer lasting saffron preservation and it is urgent to develop novel packaging approaches from renewable resources and prevent packaging waste. Here, simultaneous decontamination and quality maintenance of saffron is demonstrated, for the first time, through the synergistic application of nano-clay-loaded carboxymethyl cellulose (CMC)/polyvinyl alcohol (PVA) nanocomposites (CNCs) and cold plasmas (CP). Compared to the separate uses of CP and CMC/PVA/nano clay, our results confirm the synergies between CP and CMC/PVA/nano clay cause complete inactivation of Escherichia coli bacteria, while not significantly affecting the concentrations of the essential saffron components (safranal, crocin, and picrocrocin). Overall, the CP-treated CMC/PVA/nano clay fosters saffron preservation, through contamination removal and quality maintenance of the food product. The synergistic application of CP and CMC/PVA/nano clay thus represents a promising strategy for packaging, sterilization, and preservation of high-value food products.

Improving the bioactive ingredients and functions of asparagus from efficient to emerging processing technologies: A review

Historically, asparagus is a vegetable with abundant phytochemicals (polyphenols, saponins, asparagusic acid, and alkaloids) and crucial bioactivities (neuroprotective, antianxiety, antityrosinase, antioxidant, antibacterial, and antiasthma effects). Numerous investigations indicated that processing technologies have a significant influence on the physicochemical, functional, and microstructural characteristics of asparagus. This review presents an updated overview of novel applications of processing technologies, including ultrasound treatments (in terms of extraction, purification, and preservation), heating treatments (hydrothermal treatments, thermal treatments, and combination heating treatments), high-pressure processing, representative shelf-life extension technologies, and green extraction technologies. These physical technologies enhance the yields of bioactive substances, bioactivities and product quality. In addition, utilizing the novel technologies (ohmic heating, cold plasma, pulsed electric fields, membrane processing) and conventional technologies with novel effects to fully develop the potential of asparagus should also be taken into consideration in the future.

Effect of Drypetes gossweileri essential oil and irradiation treatments on inhibition and sensitivity of bacterial spores

This work assesses the effect of Drypetes gossweileri essential oil on germination of Bacillus spores inoculated in orange juice and milk. We also report the capacity of the essential oil at 0.25, 0.5 and 1 µg/mL to induce sensitivity of spores to some irradiation treatments. The concentrations of essential oil were chosen after sensory analysis. The results show that the essential oil inhibited spores germination with minimal inhibitory concentrations inhibiting spore germination (MICg) of 10 µg/mL in the orange juice. In milk, the spores appeared to be less sensitive with MICg varying from 20 to 40 µg/mL. The sensory analysis revealed 2.5 µg/mL as the acceptable concentration of essential oil in orange juice. The essential oil at 1 µg/mL induced the sensitivity of spore of three Bacillus to alpha radiation of 101.4 Gy. Ultraviolet-C and microwave treatments in the presence of essential oil in general led to higher inactivation of spores up to 100% in some cases.

Application of microwaves for microbial load reduction in black pepper (Piper nigrum L.)

BACKGROUND

Black pepper (Piper nigrum L.) is exposed to microbial contamination which could potentially create public health risk and also rejection of consignments in the export market due to non-adherance to microbial safety standards. The present study investigates the use of microwave (MW) radiation for microbial load reduction in black pepper and analyses the effect on quality.

RESULTS

Black pepper was exposed to MWs at two different power levels (663 and 800 W) at an intensity of 40 W g(-1) for different time intervals (1-15 min) and moisture content (110 and 260 g kg(-1) on a wet basis). The exposure of black pepper to MWs at 663 W for 12.5 min was found to be sufficient to reduce the microbial load to the permissible level suggested by the International Commission on Microbiological Specifications for Foods and the European Spice Association. The retention of volatile oil, piperine and resin was 91.3 ± 0.03, 87.6 ± 0.02 and 90.7 ± 0.05%, respectively, in MW-treated black pepper. The final moisture content after MW treatment was found to be 100 ± 1 g kg(-1) for black pepper containing initial moisture of 260 ± 3 g kg(-1) .

CONCLUSION

These results suggest that MW heating can be effectively used for microbial load reduction of black pepper without a significant loss in product quality. © 2016 Society of Chemical Industry.