β-谷甾醇和γ-谷维素的键合物对软质奶油的水分分布影响

Effect of Bonding Mixture of β- Sitosterol andγ- Oryzanol on the Moisture Distribution of Soft Margarine

利用低场核磁共振研究β-谷甾醇和γ-谷维素的键合物作为油脂质构剂时,对高水分软质奶油产品水分状态和分布的影响。采用CPMG脉冲序列获得样品的横向弛豫时间T2。结果表明,核磁共振谱中弛豫时间为40～150 ms的T2部分可反映油脂中氢质子的信息;β-谷甾醇和γ-谷维素的键合物使软质奶油中结合水和自由水的氢质子向低弛豫时间迁移,水分子的流动性降低,自由水含量减少,表明键合物与水分子有较强的结合效应。当β-谷甾醇和γ-谷维素的键合物添加量为4%时,自由水含量比空白样减少17.8%,偏振光显微图片及感官分析显示β-谷甾醇和γ-谷维素键合物使软质奶油样品的微观结构和感官品质得到改善。

Low - field nuclear magnetic resonance （ Lf - NMR） has been utilized to research the water state and distribution of high - moisture soft margarine. Bonding mixture of β - sitosterol and γ - oryzanol has been utilized as grease texture material in the experiment of the paper. The proton transverse relaxation time （T2） was determined by Carr- Purcell -Meiboom- Gill （CPMG） pulse sequences. The distribution of the T2 relaxation indicated that the relaxation time of 40 ～ 150 ms region could reflect the information of fat in the samples. The T2 relaxation time of bound water and free water were decreased, when adding bonding mixture of β - sitosterol and γ - oryzanol, the free water content demonstrated strong bonding effect between bonding mixture and water molecules significantly. When the addition of bonding mixture reached 4% , it had a 17.8% decreasing in free water compared to the blank sample. As a result, the bonding mixture of β - sitosterol and γ - oryzanol could improve the microstrueture and sensory quality of the soft margarine sample, which was observed by polarized light microscopy and sensory evaluation.