为研究不同厚度聚乙烯(PE)膜包装对甜玉米冷库贮藏期间品质的影响,采用0.02 mm和0.03 mm PE膜包装甜玉米,并于0℃冷库中贮藏,考察其感官评分、失重率、皱缩率、色泽的变化,并对其呼吸速率、乙烯生成率及可溶性固形物、可溶性糖、淀粉含...为研究不同厚度聚乙烯(PE)膜包装对甜玉米冷库贮藏期间品质的影响,采用0.02 mm和0.03 mm PE膜包装甜玉米,并于0℃冷库中贮藏,考察其感官评分、失重率、皱缩率、色泽的变化,并对其呼吸速率、乙烯生成率及可溶性固形物、可溶性糖、淀粉含量进行测定,使用电子鼻比较其风味品质的差异。结果表明:0.02 mm PE膜包装可显著降低甜玉米贮藏过程中的呼吸速率,抑制乙烯生成,延缓苞叶失绿黄化,保持甜玉米籽粒色泽,提高甜玉米可溶性固形物和可溶性糖含量,降低其淀粉含量,从而维持甜玉米的贮藏品质和风味品质。试验表明,0.02 mm PE膜包装在维持甜玉米采后贮藏品质方面有较好的效果,该研究为甜玉米采后包装材料的选择提供一定参考和数据支撑。展开更多
The current study presents the characterization of three types of materials after exposure to solar UV radiation. The selection of the materials is related to socio-economic aspects and rural activities in the northwe...The current study presents the characterization of three types of materials after exposure to solar UV radiation. The selection of the materials is related to socio-economic aspects and rural activities in the northwest of Argentina (a.k.a. NOA). The objective was to establish a time parameter that allows estimating the durability of the materials according to their use. One of the materials is used as a protective cover (polyethylene film) of greenhouses, which are used for crop cultivation in the area. Another material is used in photovoltaic modules (PVMs), which are used to supply energy in isolated areas and the third material is sunscreen used by people that are exposed to UV radiation during rural activities. Degradation or deterioration of the materials was monitored using different spectroscopic assays: infrared was used to detect any structural changes in the material, X-rays were used for possible changes in the crystalline structure of the material, and spectral transmittance as this property is likely to be affected by changes in the structure of the material. The results showed that degradation of polyethylene seems to be related to the diminution in transparency and the loss of mechanical resistance with increasing exposure time. The decrease in transparency of one of the layers of a PVM caused a considerable decrease in the energy generated, whereas the sunscreens with a low sun protection factor (SPF) rapidly lost their protective properties and changed their photostability properties. Our results revealed a relationship between relative transmittance loss and exposure timse, which allows estimating the stability of different materials.展开更多
文摘为研究不同厚度聚乙烯(PE)膜包装对甜玉米冷库贮藏期间品质的影响,采用0.02 mm和0.03 mm PE膜包装甜玉米,并于0℃冷库中贮藏,考察其感官评分、失重率、皱缩率、色泽的变化,并对其呼吸速率、乙烯生成率及可溶性固形物、可溶性糖、淀粉含量进行测定,使用电子鼻比较其风味品质的差异。结果表明:0.02 mm PE膜包装可显著降低甜玉米贮藏过程中的呼吸速率,抑制乙烯生成,延缓苞叶失绿黄化,保持甜玉米籽粒色泽,提高甜玉米可溶性固形物和可溶性糖含量,降低其淀粉含量,从而维持甜玉米的贮藏品质和风味品质。试验表明,0.02 mm PE膜包装在维持甜玉米采后贮藏品质方面有较好的效果,该研究为甜玉米采后包装材料的选择提供一定参考和数据支撑。
文摘The current study presents the characterization of three types of materials after exposure to solar UV radiation. The selection of the materials is related to socio-economic aspects and rural activities in the northwest of Argentina (a.k.a. NOA). The objective was to establish a time parameter that allows estimating the durability of the materials according to their use. One of the materials is used as a protective cover (polyethylene film) of greenhouses, which are used for crop cultivation in the area. Another material is used in photovoltaic modules (PVMs), which are used to supply energy in isolated areas and the third material is sunscreen used by people that are exposed to UV radiation during rural activities. Degradation or deterioration of the materials was monitored using different spectroscopic assays: infrared was used to detect any structural changes in the material, X-rays were used for possible changes in the crystalline structure of the material, and spectral transmittance as this property is likely to be affected by changes in the structure of the material. The results showed that degradation of polyethylene seems to be related to the diminution in transparency and the loss of mechanical resistance with increasing exposure time. The decrease in transparency of one of the layers of a PVM caused a considerable decrease in the energy generated, whereas the sunscreens with a low sun protection factor (SPF) rapidly lost their protective properties and changed their photostability properties. Our results revealed a relationship between relative transmittance loss and exposure timse, which allows estimating the stability of different materials.
