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Asparagus (Asparagus officinalis L.) has short shelf-life due to the high metabolic activity of the apical meristems. Storage at low temperature and high relative humidity is used commercially to keep fresh asparagus spears. Techniques denominated “Hurdley technologies” (UV-C or gamma irradiation) have been tested in fruits and vegetables to extend postharvest life. These technologies were used to extend postharvest shelf life of asparagus spears by inhibition of meristematic activity. Spears were irradiated with UV-C at dosages of 2.46, and 4.93 kJ m-2 and gamma irradiation at 1 and 1.5 kGy, before storage at 2°C and 90% relative humidity (RH) for 20 days. Metabolic heat (Rq) was measured in apical meristems, as well as whole spear respiration, sugars content, water potential components and color descriptors. Metabolic heat and whole spears respiration rate did not show differences due to effect of UV-C treatments, while spears treated with gamma radiation showed a metabolic activity inhibition of 10 and 15% for 1 and 1.5 kGy, respectively, while whole spear respiration rate was not affected. Changes in color variables showed a slight reduction in gloss. Sugars content in UV-C remained unchanged, while gamma radiation induced a reduction in glucose. An increase in fresh weight loss was noticeable on those treated with gamma irradiation. No changes in water potential components were observed. It was concluded the treatments used did not reported positive benefits in extending asparagus spears shelf life.

The extensive use of petroleum-based plastics has led to serious environmental problems worldwide. A viable alternative is to replace these polymers with those that are biodegradable. Polylactic acid (PLA) is a biodegradable polymer with properties that are similar to petroleum-based polymers. However, it has some drawbacks such as brittleness, poor impact strength, low heat distortion, and poor difficulties in thermal stability during processing. In this study, we describe the use of modified jute fibres to reinforce the PLA polymer matrix in order to improve its adhesion. Biocomposites of PLA and cut jute fibres (CJF) were prepared by extrusion. The CJF were modified using three different physical and chemical pretreatments (alkaline, maleic anhydride functionalization, and gamma irradiation). The results showed improvement in the mechanical, thermal, structural, and morphological properties of PLA biocomposites with 10% wt. CJF that were subjected to gamma irradiation at 50 kGy. The biocomposites developed could be used for rigid food packaging and are a good alternative for reducing domestic dependence on petroleum-based thermoplastics.