全脂乳粉和脱脂乳粉在1kHz～10MHz下的介电特征研究  

Dielectric properties of whole milk powder and skimmed milk powder from 1kHz to 10MHz

作　　者：金亚美[1] 王宁[1] 孟彤[1] 崔文华[1] 郭光辉[1] 杨哪[1] 金征宇[1] 徐学明[1] 

机构地区：[1]江南大学食品科学与技术国家重点实验室,江南大学食品学院,江苏无锡214122

出　　处：《食品工业科技》2012年第8期152-155,共4页Science and Technology of Food Industry

基　　金：国家自然科学基金(31071490)

摘　　要：分别研究了各4种不同品种的全脂乳粉和脱脂乳粉在1kHz～10MHz波段的介电特性。结果发现:随着频率的增加,全脂乳粉和脱脂乳粉的ξ'和ξ″值呈单调递减趋势;全脂乳粉的ξ'和ξ″值都高于脱脂乳粉,相同类型乳粉各品种间的ξ'和ξ″差异不大;全脂乳粉的ξ″值在103～105Hz频率段减小趋势明显,且ξ″值的对数与频率的对数成线性反比关系,而脱脂乳粉无此规律;全脂乳粉和脱脂乳粉的穿透深度Dp随频率的提高而减小,两类乳粉的介电特性差异可能与它们各自的脂肪和乳糖含量有关。The dielectric constant and loss factor of powder of four whole milk and skimmed milk over the frequency range from lkHz to 10MHz were measured at room temperature.The results indicated that the dielectric constant, loss factor and depth of penetration of powder of whole milk and skimmed milk decreased monotonically as frequency increased,and there were no obvious difference between the cultivars of powder on whole milk and skimmed milk.The dielectric constant and loss factor of whole milk powder were higher than those of skimmed milk.The whole milk powder exhibited significant drop in loss factor and inverse proportion linear relationships were evident between the log of frequency and loss factor below 10^5Hz, but this was not found in the skimmed milk powder.The contents of fat and lactose were related with dielectric properties.

关 键 词：全脂乳粉 脱脂乳粉 介电特性 

分 类 号：TS252.51[轻工技术与工程—农产品加工及贮藏工程]