助干剂对真空冷冻干燥岗稔果粉品质的影响

目的]研究4种助干剂对真空冷冻干燥岗稔果粉品质的影响,为岗稔果粉的加工提供参考依据.方法]采用单因素试验,分析麦芽糊精、羧甲基纤维素钠(CMC-Na)、β-环糊精和大豆分离蛋白4种助干剂的不同添加量对真空冷冻干燥岗稔果粉花色苷含量、水含量、速溶时间和感官评价的影响;在此基础上,以综合评分为评价指标,通过正交试验确定助干剂的最佳配方.结果]单独添加麦芽糊精和β-环糊精能显著降低岗稔果粉水含量(P<0.05,下同),CMC-Na能显著提高岗稔果粉花色苷含量,大豆分离蛋白能明显缩短岗稔果粉的速溶时间.助干剂的最佳配方为:麦芽糊精与岗稔果汁中固形物质量比1:1、CMC-Na添加量1.2%、β-环糊精添加量2.5%、 大豆分离蛋白添加量0.5%,在此配方下按照工艺流程制备的岗稔果粉花色苷含量为450.10 mg/L、水含量为6.22%、速溶时间为23.0 s、感官评分为85.8分,计算综合评分得90.8分;果粉品质优良,其色泽绛红,质地细腻,有岗稔特殊风味.结论]以添加麦芽糊精与岗稔果汁中固形物质量比为1:1的果汁为基底液,并添加1.2%CMC-Na、2.5%β-环糊精和0.5%大豆分离蛋白,再利用真空冷冻干燥法制备的岗稔果粉品质优良,营养成分保留全面,在实际生产中可按此比例进行调配.

Effects of drying aids on quality of vacuum freeze-drying Rhodomyrtus tomemtosa powder

Objective]Effects of four drying aids on vacuum freeze-drying Rhodomyrtus tomemtosa powder were stu-died to provide reference for R. tomemtosa powder processing. Method]Effects of additions of maltodextrin, sodium carboxymethyl cellulose(CMC-Na), β-cyclodextrin and soy protein isolate on nthocyanin content, moisture content, in-stant time and sensory evaluation score were analyzed by single factor experiment. On this basis, comprehensive evaluation score was used as index. The optimal drying recipe was determined by orthogonal experiment. Result]Addition of mal-todextrin or β-cyclodextrin alone significantly decreased moisture content in R. tomemtosa powder (P<0.05 ,the same below ) ; CMC-Na significantly increased nthocyanin content; and soy protein isolate shortened instant time. The optimal drying aids recipe was as follows:mass ratio of maltodextrin to solid mater in R. tomemtosa juice 1:1, CMC-Na addition 1.2%, β-cyclodextrin addition 2.5%, and soy protein isolate addition 1.5%. Under these conditions, anthocyanins content in R. tomemtosa powder was 450.1 mg/L , moisture content 6.22%, instant time 23.0 s, sensory evaluation score 85.8 and comprehensive evaluation score 90.8. The powder was in good quality with red color, delicate texture and special flavor of R. tomemtosa. Conclusion]Juice with mass ratio of maltodextrin to solid mater in R. tomemtosa juice being 1:1 is used as base, adding 1.2% CMC-Na, 2.5% β-cyclodextrin, and 1.5% soy protein isolate. The quality of R. tomemtosa powder by vacuum freeze-drying method is qualified. Most nutrient components are retained. In actual production, this recipe can be applied to process R. tomemtosa powder.