Valle-Gómez Amanda, Borja-Urby Raúl, Ortiz-Moreno Alicia, Téllez-Medina Darío Iker
Departamento de Ingeniería Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Unidad Profesional Adolfo López Mateos, Zacatenco, Av. Wilfrido Massieu 399, Col. Nueva Industrial Vallejo, Gustavo A. Madero, Ciudad de México 07738, Mexico.
Centro de Nanociencias y Micro y Nanotecnologías, Instituto Politécnico Nacional, Wilfrido Massieu s/n, UPALM, Gustavo A. Madero, Ciudad de Mexico 07738, Mexico.
Foods. 2024 Nov 21;13(23):3717. doi: 10.3390/foods13233717.
Avocado ( Mill.) is a fruit with a high content of unsaturated fatty acids and bioactive compounds, whose consumption has considerably increased in the USA and Europe. Thus, the conservation of the avocado mesocarp (pulp) has become more relevant. Avocado pulp was processed using a scraped-surface heat exchanger (SSHE) system to extend the shelf-life of the mesocarp. Through analysis with X-ray diffraction and HRTEM, it was possible to identify crystalline-type structures in the avocado pulp processed and stored at 4 °C. The 2θ-angles and d-spacing of the structures that reported the highest diffraction intensity are comparable to the polymorphs β' reported in the literature for fatty acid mixtures processed under similar conditions. Furthermore, the X-ray signals suggest the presence of polymorphs α and β in all samples processed and stored at different temperatures. Calorimetry analysis showed curves with first-order phase changes as indicative of crystallization-type transitions. The shelf-life evaluation of the avocado pulp showed that the crystallization process minimized the losses of antioxidant capacity and prevented color change, while the enzyme polyphenol oxidase remained inactivated. The changes induced by the SSHE continuous processing applied might represent an alternative to obtaining avocado products that preserve avocado's properties and extend its shelf-life.
鳄梨（Persea americana Mill.）是一种富含不饱和脂肪酸和生物活性化合物的水果，其在美国和欧洲的消费量大幅增加。因此，鳄梨中果皮（果肉）的保存变得更加重要。使用刮板式换热器（SSHE）系统对鳄梨果肉进行处理，以延长中果皮的保质期。通过X射线衍射和高分辨率透射电子显微镜分析，能够在4℃下加工和储存的鳄梨果肉中识别出晶体结构类型。报告最高衍射强度的结构的2θ角和d间距与文献中报道的在类似条件下加工的脂肪酸混合物的β'多晶型物相当。此外，X射线信号表明在不同温度下加工和储存的所有样品中都存在α和β多晶型物。量热分析显示具有一级相变的曲线，表明为结晶型转变。鳄梨果肉的保质期评估表明，结晶过程使抗氧化能力的损失最小化并防止了颜色变化，而多酚氧化酶保持失活状态。所应用的SSHE连续加工引起的变化可能代表了一种获得保留鳄梨特性并延长其保质期的鳄梨产品的替代方法。
