Moura José R R de O, de Morais Blenda R S, da Silva João H F, Alves Amanda S S, Brandão Shirley C R, Azoubel Patricia M
Departamento de Engenharia Química, Universidade Federal de Pernambuco, Av. Prof. Arthur de Sá, s/n, Cidade Universitária, Recife 50740-521, PE, Brazil.
Departamento de Nutrição, Universidade Federal de Pernambuco, Av. Moraes Rego, s/n, Cidade Universitária, Recife 50670-901, PE, Brazil.
Foods. 2024 Aug 9;13(16):2502. doi: 10.3390/foods13162502.
There is a growing interest in the food industry in new drying technologies that reduce the time required for dehydration, combined with low energy consumption, low environmental impact, and maintenance of the overall quality of the product. This work investigated convective drying of pumpkin with and without ultrasound-organic (citric or acetic) acid pretreatment for different durations (10, 20, and 30 min). Drying was carried out at 60 °C, and the Wang and Singh model had the best fit for the experimental data. Samples pretreated for 30 min had the shortest drying times. Water diffusivities ranged from 6.68 × 10 m/s to 7.31 × 10 m/s, with the pretreated samples presenting the highest values. The dried pumpkin water activity values were below 0.60. Regarding color parameters, there was a slight increase in luminosity, a slight reduction in *, and a significant increase in *. Drying resulted in the loss of ascorbic acid and phenolic compounds, but the samples pretreated with citric acid showed better retention. There was also a reduction in the total carotenoid content, but samples pretreated with acetic acid for 10 and 20 min showed the best retention.
食品行业对新型干燥技术的兴趣日益浓厚，这些技术能减少脱水所需时间，同时具备低能耗、低环境影响以及保持产品整体质量的特点。本研究考察了南瓜在有无超声 - 有机（柠檬酸或乙酸）酸预处理不同时长（10、20和30分钟）下的对流干燥情况。干燥在60°C下进行，Wang和Singh模型对实验数据拟合效果最佳。预处理30分钟的样品干燥时间最短。水分扩散率在6.68×10⁻¹² m²/s至7.31×10⁻¹² m²/s之间，预处理样品的值最高。干燥南瓜的水分活度值低于0.60。关于颜色参数，亮度略有增加，*值略有降低，*值显著增加。干燥导致抗坏血酸和酚类化合物损失，但用柠檬酸预处理的样品保留效果更好。总类胡萝卜素含量也有所降低，但用乙酸预处理10和20分钟的样品保留效果最佳。
