摘要
以新鲜柠檬皮渣为原料,采用热风恒温、热风梯度干燥、真空干燥、冷冻干燥、微波干燥、微波-热风联合干燥及冷冻-热风联合干燥等不同方式对柠檬皮渣进行干燥处理,制备提取果胶用的柠檬干渣。研究不同干燥方式对柠檬皮渣感官评分、能耗、果胶得率等指标的影响,并对各指标采用变异系数法加权评分,总分最高的为最佳干燥方法。结果表明,不同干燥方式对各指标影响显著(P<0.05),加权评分最高的是热风梯度干燥,即采用两段式干燥,70℃下干燥至含水量(40±2)%后,在50℃下干燥至含水量8%～10%,所得干渣感官评分82分、复水比为4.18、单位能耗为29.00 kJ/g、果胶得率12.66%、果胶黏度3.44 MPa·s以及酯化度56.89%。采用热风梯度干燥操作简单、能耗低,是一种值得深入研究的干燥方式。
Dried lemon pomace pectin extracts were produced from fresh lemon pomace by using different drying methods, including hot air drying, air gradient drying, vacuum drying, freeze drying, microwave drying, microwave-air drying, and freeze-air drying. Indexes such as sensory score, drying energy consumption, and the yield of pectin of dried lemon pomace among different drying methods were measured. The variation coefficient weight method was used to determine their comprehensive scores to find the optimal drying method. The results showed that different drying methods had significant effects on all parameters(P<0.05). Air gradient drying had the highest comprehensive score, which was hot-air drying with a two-stage drying temperature: the pomace was dried to contain(40±2)% moisture at 70 ℃ first, followed by drying to contain 8%-10% moisture at 50 ℃. The sensory score, rehydration rate, energy consumption, pectin yield, pectin viscosity, and the degree of esterification of pectin were 82 points, 4.18, 29 kJ/g, 12.66%, 3.44 MPa·s, and 56.89%, respectively. Hot-air gradient temperature drying is easy and energy-saving,and is a promising drying method for further study.
作者
刘江
张诗琪
雷激
苏菲烟
任倩
LIU Jiang;ZHANG Shiqi;LEI Ji;SU Feiyan;REN Qian(Food and Bioengineering College,Xihua University,Chengdu 610039,China)
出处
《食品与发酵工业》
CAS
CSCD
北大核心
2019年第7期242-249,共8页
Food and Fermentation Industries
