改良纤维素膜在南香杂柑果汁超滤澄清中的应用

选用南香杂柑(Citrus unshiu×Citrus clementina)为材料,采用Millipore BioProcess Division的Ultracel-PL系列改良纤维素膜对南香果汁进行超滤澄清试验。结果表明,Plctk-30ku膜的最佳操作条件为:操作压力为30Pa,温度为40℃,流速为0.10m·s-1;Plctk-30ku膜对总可溶性固形物、还原糖、总酸、维生素C等主要营养成分的保留率超过80%,D-柠檬烯的保留率为90.2%,而对果胶及类胡萝卜素的保留率在1%以下,主要营养成分及香气的保留率均比对照膜(Plcgc-10ku)要好。因此Plctk-30ku膜对南香果汁有较好的澄清效果,适合作为果汁浓缩的前处理。

Clarification of Nankou juice by ultra-filtration using modified fibre membranes

The conditions of ultra-filtration using modified membrane,i.e.Plctk-30 ku for the clarification of Nankou hydrid orange juice were optimized by single factor test and orthogonal design.And then the main nutritional components and aro-matic compounds of the juices before and after ultra-filtration using modified membranes of Plcgc-10 ku and Plctk-30 ku were analyzed.The results showed that the optimum conditions for Plctk-30 ku operation were:30 Pa of pressure,40 ℃ and 0.10 m·s-1 of flow velocity.After ultra-filtration under this combination of parameters for Plctk-30 ku,the values of total sol-uble solids,total sugar and total acid and ascorbic acid in juices retained more than 80% of those before ultra-filtration while D-limonene,the particular aromatic compound in citrus fruit was hold at 90.2%.But the contents of pectin and carotenoids of juice decreased to the level less than 1%.The retained rate of low molecular nutritional compounds and volatiles for the Plctk-30 ku was higher than that of Plcgc-10 ku.These facts indicate that Plctk-30 ku should be suitable for the pretreat-ment of concentration of Nankou juice.