牛奶的年龄是否会影响其中红外光谱和预测?
S Magro1, N W Sneddon2, A Costa3
1Department of Agronomy, Food, Natural Resources, Animals and Environment, University of Padova, Viale dell'Università 16, 35020 Legnaro (PD), Italy.
Food chemistry
|January 14, 2024
概括
牛奶样本的年龄会影响化学分析和中红外光谱. 虽然主要成分保持稳定,但光谱变化表明牛奶老化,允许使用光谱检测质量控制来准确预测牛奶的年龄.
科学领域:
- 乳制品科学 乳制品科学
- 分析化学 分析化学
- 频谱学是一种光谱学.
背景情况:
- 标准化牛奶分析需要样本的保存和运输,因此储存时间是一个关键因素.
- 样品老化可能会改变牛奶的化学成分及其中红外 (MIR) 光谱特性.
- 确保牛奶分析的可靠性对于官方测试,支付系统和法律目的至关重要.
研究的目的:
- 评估储存时间对MIR光谱学预测的牛奶特征的重复性和可重复性的影响.
- 评估光谱和化学测量的能力,以根据年龄区分牛奶样本.
- 为了确定使用MIR光谱数据预测牛奶年龄的可行性.
主要方法:
- 在不同时间点/年龄段对牛奶样本的分析.
- 对MIR预测的特征 (例如脂肪,蛋白质) 的重复性和可重复性的评估.
- 对样本年龄分类的光谱数据应用差分分析.
主要成果:
- 关键的牛奶成分在不同样本年龄 (天) 中显示出一致的可重复性.
- 观察到与样本老化和矩阵恶化相关的可检测的光谱变化.
- 差别分析在验证乳龄预测时实现了77%的分类准确性.
结论:
- 中红外光谱与化学测量相结合,可以有效地预测牛奶的年龄.
- 频谱分析提供了一种可行的方法来监测质量关键应用中的牛奶样本年龄.
- 这种方法提高了用于官方用途,支付系统和法律合规性的牛奶分析的可靠性.
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