相关实验视频
Updated: May 20, 2025

09:48
Original Experimental Approach for Assessing Transport Fuel Stability
Published on: October 21, 2016
9.3K
通过振动光谱技术监测油和油的氧化稳定性
Ingrid A Moraes1, Javier E L Villa2, Rosiane L Cunha1
1Department of Food Engineering and Technology, School of Food Engineering, University of Campinas, SP, Brazil.
Food research international (Ottawa, Ont.)
|May 17, 2025
概括
近红外 (NIR) 和拉曼光谱学提供了环保的方法来监测储存期间的油的氧化稳定性. 这些技术可以准确预测组合的变化,为传统测试提供更快,更安全的替代方案.
科学领域:
- 食品科学与技术 食品科学与技术
- 分析化学 分析化学
- 频谱学是一种光谱学.
背景情况:
- 氧化稳定性对于油和油来说至关重要,但传统的评估方法是繁的,对环境有害的.
- 在储存过程中,湿度,温度和光线等因素会影响oleogel的组成,结构和感觉属性.
- 开发快速,非破坏性和环保的分析技术对于质量控制至关重要.
研究的目的:
- 评估近红外 (NIR) 和拉曼光谱在预测油的氧化稳定性方面的有效性.
- 评估这些光谱方法作为传统的,化学密集型质量控制技术的可持续替代品.
- 在8个月的储存期内监测油脂凝的组成变化.
主要方法:
- 使用以蜜蜂为结构剂的向日,大豆和橄油生产油.
- 在为期8个月的储存研究中,应用非破坏性NIR和拉曼光谱来分析油脂凝.
- 在光谱数据上使用预处理技术和主要成分分析 (PCA).
- 使用部分最小平方差分分析 (PLSDA) 和部分最小平方回归 (PLSR) 开发分类和回归模型.
主要成果:
- 在分类储存期方面,PLSDA模型实现了83%的准确性 (Raman) 和71%的准确性 (NIR).
- 对于过氧化物指数和自由脂肪酸含量,PLSR模型表现出强大的预测性能,其残余预测偏差和确定系数分别超过2.5和0.8.
- 光谱数据有效地捕获了受储存条件影响的光谱变化.
结论:
- 尼尔射线和拉曼光谱对于分类和预测储存期间油的组成变化非常有希望.
- 与传统分析方法相比,这些技术提供了更大的灵活性和降低了环境风险.
- 进一步的研究应该探索各种油探器,以确认这些光谱方法的稳定性.
相关概念视频
IR and UV–Vis Spectroscopy of Aldehydes and Ketones
5.1K
Infrared spectroscopy, also known as vibrational spectroscopy, is mainly used to determine the types of bonds and functional groups in molecules. In aldehydes and ketones, the carbonyl (C=O) bond shows an absorption around 1710 cm-1. The C=O bond vibration of an aldehyde occurs at lower frequencies than that of a ketone. In addition to the C=O absorption in an aldehyde, the aldehydic C–H bond also gives two peaks in the 2700–2800 cm-1 range. This absorption, coupled with the...
5.1K
IR and UV–Vis Spectroscopy of Carboxylic Acids
3.7K
In IR spectroscopy of carboxylic acids, the C=O bond shows a characteristic band between 1710 and 1760 cm⁻¹, and the O–H bond exhibits a broad band between 2500 and 3300 cm⁻¹.
However, the stretching absorptions for the C=O bond vary depending on the structure of carboxylic acids. The C=O bond of the free carboxylic acids shows a higher stretching frequency, 1760 cm−1, while H-bonded carboxylic acids (dimers) exhibit stretching absorptions at a lower frequency,...
However, the stretching absorptions for the C=O bond vary depending on the structure of carboxylic acids. The C=O bond of the free carboxylic acids shows a higher stretching frequency, 1760 cm−1, while H-bonded carboxylic acids (dimers) exhibit stretching absorptions at a lower frequency,...
3.7K
IR Spectroscopy: Molecular Vibration Overview
1.8K
When Infrared (IR) radiation passes through a covalently bonded molecule, the bonds transition from lower to higher vibrational levels. The fundamental vibrational motions that result in infrared absorption can be classified as stretching or bending vibrations.
Stretching vibrations are vibrational motions that occur along the bond line, changing the bond length or distance between two bonded atoms. They are further distinguished as symmetric or asymmetric. In symmetric stretching, the...
Stretching vibrations are vibrational motions that occur along the bond line, changing the bond length or distance between two bonded atoms. They are further distinguished as symmetric or asymmetric. In symmetric stretching, the...
1.8K
Spectroscopy of Carboxylic Acid Derivatives
2.2K
Infrared spectroscopy is primarily used to determine the types of bonds and functional groups. In carboxylic acid derivatives, a typical carbonyl bond absorption is observed around 1650–1850 cm−1. For esters, the absorption is recorded at around 1740 cm−1, while acid halides show the absorption at about 1800 cm−1. Another acid derivative, the acid anhydrides, exhibit two carbonyl absorption around 1760 cm−1 and 1820 cm−1, arising from the symmetrical and...
2.2K
Radical Autoxidation
2.1K
The oxidation of an organic compound in the presence of air or oxygen is called autoxidation. For example, cumene reacts with oxygen to form hydroperoxide. Autoxidation involves initiation, propagation, and termination steps. Many organic compounds are susceptible to autoxidation—especially ethers in the presence of oxygen, which form hydroperoxides. Even though this reaction is slow, old ether bottles contain small amounts of peroxide, which leads to laboratory explosions during ether...
2.1K
UV–Vis Spectroscopy: Molecular Electronic Transitions
1.3K
In Ultraviolet–Visible (UV–Vis) spectroscopy, the absorption of electromagnetic radiation is used to probe the electronic structure of molecules. This technique provides insights into molecular electronic transitions, particularly the movement of electrons between different molecular orbitals. Radiation is absorbed if the energy of the electromagnetic radiation passing through the molecule is precisely equal to the energy difference between the excited and ground states. During this...
1.3K

