Rapid Milk Analysis with Timegated® Raman Spectroscopy
08:54 Mon 23.11.2020
Raman spectroscopy has been gaining ground in the last decade for food systems analyses. The vibrational fingerprint offers a wealth of information on the content and structure of the studied sample.
Quality control of both the raw ingredients and the end products in the food industry is of paramount importance. With the exponential increase in lifestyle diseases, more and more people are moving towards vegan food alternatives.
A recent study says that for every three percent increase in calories from plant protein risk of death is reduced by ten percent. One of the main products in the food industry is milk. Due to lactose intolerance and various allergies associated with animal-source milk, plant-based milk products are flourishing.
Raman spectroscopic technique has been employed for characterizing milk products and their ingredients. Fluorescence is a big challenge for Raman spectroscopic technique since plant-based products have high fluorescence compared to their animal-based counterparts.
Figure 1. Raw Raman spectra of (A) cow milk (B) oat milk and (C) soy milk measured from continuous Raman spectroscope at 532 nm and 785 nm laser excitation, and 532nm laser excitation of PicoRaman with Y offset for clarity.
In this work, the continuous wave Raman spectroscopic technique was compared to time-gated Raman technology on different varieties of milk and milk products. First, animal-source milk was analyzed and compared with soy and oat milk. Further cheese, lactose, whey, and vegan protein supplementary powders were tested. To exemplify the quantitative efficacy of this technique, cow milk with different fat and lactose content was analyzed.