影响生牛乳冰点的因素分析  

Analysis of Factors Affecting the Freezing Point of Raw Milk

作　　者：孙玉荣 胡文秀 李君冉 任利强 王海斌 胡冬梅 田晓芳 SUN Yurong;HU Wenxiu;LI Junran;REN Liqiang;WANG Haibin;HU Dongmei;TIAN Xiaofang(Mengniu Dairy(Chabei)Co.,Ltd.,Zhangjiakou Hebei 076481)

机构地区：[1]蒙牛乳业(察北)有限公司,河北张家口076481

出　　处：《中国乳业》2025年第3期65-70,共6页China Dairy

基　　金：呼和浩特市科技计划项目(2021-农-重-1)。

摘　　要：[目的]通过探究影响生牛乳冰点的因素,分析温度变化、掺水量及掺入糊精和氯化钠对冰点检测结果的作用规律,为生牛乳质量检测及掺假判定提供科学依据。[方法]通过逐步升高生牛乳样品温度,记录冰点随温度变化的趋势;向生牛乳中按体积比掺入水,测定不同掺水量下的冰点;分别添加糊精和氯化钠,定量分析冰点变化,采用线性回归模型计算温度、掺水量及掺假物质添加量与冰点的相关性。[结果]发现平均温度每上升1℃,冰点下降0.0010℃。掺水量(体积比)为1%与2%时,无法判定生牛乳是否掺水;掺水量增至5%及以上时,可明显判定为掺水;平均每掺水1%,冰点平均上升0.0030℃。糊精添加量为0.01~0.05 g/100 mL(折算掺入糊精每增加0.01 g/100 mL)时,冰点平均下降0.0046℃;氯化钠添加量每增加0.01 g/100 mL时,冰点平均下降0.0017℃。[结论]随生牛乳样品温度逐渐升高,冰点检测结果呈逐渐下降趋势;随掺水量增加,冰点相应升高;生牛乳掺入糊精和氯化钠后冰点逐渐下降,掺入量越多,冰点下降幅度越大。[Objective]By exploring the factors affecting the freezing point of raw milk,the effects of temperature changes,water content and dextrin and sodium chloride on freezing point detection results were analyzed to provide scientific basis for quality detection and adulteration determination of raw milk.[Method]By gradually increasing the temperature of the raw milk samples,the trend of freezing point changed with temperature was recorded.Water was added into raw milk according to volume ratio to determine the freezing under different water content.Dextrin and sodium chloride were added to quantitatively analyze the change of freezing point.Linear regression model was used to calculate the correlation between temperature,water content and adulterant addition and freezing point.[Result]It was found that the freezing point decreases by 0.0010℃ for every 1℃ increase in average temperature.When the water content(volume ratio)was 1% and 2%,it was impossible to determine whether raw milk was watered.When the water content increased to 5% or more,it could be clearly judged as water addition on average,the freezing point value increased by 0.0030℃ for each 1% water addition.The average freezing point decreased by 0.0046℃ when the dextrin addition amount was 0.01~0.05 g/100 mL(calculated as an increase of 0.01 g/100 mL per dextrin addition).The freezing point decreased by an average of 0.0017℃ for every 0.01 g/100 mL increase of sodium chloride addition.[Conclusion]As the temperature of raw milk samples increased gradually,the freezing point showed a decreasing trend.With the increased of content,the freezing point increased correspondingly.The freezing point of raw milk decreased gradually when dextrin and sodium chloride were added,and the more the amount was added,the greater the freezing point decreased.

关 键 词：生牛乳 冰点 温度效应 掺水检测 掺假物质 

分 类 号：TS2[轻工技术与工程—食品科学与工程]