Analysis of volatile compounds in powdered milk for infant nutrition by direct desorption (CIS4–TDU) and GC–MS

Abstract

Direct thermal desorption coupled with the Gas Chromatography-Mass Spectrometry (TDU-CIS4-GC-MS) technique applied to powdered milk was used as a novel approach for the characterization and quantification, as relative abundance, of volatile organic compounds (VOCs). The aim of this study was to exploit the potential applications and setup conditions of the CIS4-TDU-GC-MS technique for the identification of oxidized or non-oxidized samples of powdered milk for infant nutrition, subjected to accelerated aging through the changes in their VOCs profile over time. Thermal desorption at 30°Cand subsequent cryotrapping at -40°C with a Gerstel Liner-in-Liner system, allowed a direct thermal desorption and cryotrapping of VOCs without any memory effect, thus avoiding sample preparation and contamination. The analyses led to the identification of several characteristic off-flavors in the oxidized samples, which were used as molecular markers to discriminate samples with different 2 oxidation degrees. Finally, VOC contaminants possibly present in the packaging can also be identified with this technique.

Sensorial, cultural and volatile properties of milk, dairy powders, yoghurt and butter: A review

“…Francesca et al. (2015) associated pentanal, hexanal, octanal, 2‐heptenal, nonanal, 2‐octenal, 2‐nonenal, 2‐decenal, 2,4‐nonadienal, 2‐undecenal, 2,4‐decadienal with oxidation in powdered milk, defined as ‘pungent’, ‘green (or herbaceous)’, ‘fat’ and ‘food‐fried’. Boltar et al.…”

“…Francesca et al. (2015) exploited the potential applications and setup conditions of the automated Gerstel TD (Gerstel GmbH & Co, Mṻlheim, Germany) using microporus sinthered glass (TDU‐CIS4–GC–MS) and cryogenic trapping for the identification of oxidized or non‐oxidized volatile compounds of powdered milk at 30°C for 30 min. They identified 17 VOC mainly consisting of aldehydes, ketones, acids and alcohols.…”

Inhibition effect of nitrogen‐filled technology on flavor degradation of infant nutrition powder

“…Studies had shown that the above substances were characteristic flavor substances in milk powder, and were easily oxidized with the extension of storage time, and then the content decreased (Francesca et al, 2015;Vincenzetti et al, 2018).…”

“…Therefore, nitrogen is rarely used in the whole process of processing and packaging, and its products are also few. Federico et al (Francesca et al, 2015) analyzed the flavor of milk powder through GC–MS, and found that aldehydes and ketones produced unpleasant flavors. However, GC‐IMS technology is more rapid than GC–MS in food flavor detection, and has gradually attracted the attention of researchers (Wang et al, 2020).…”

Oxidative Quality of Dairy Powders: Influencing Factors and Analysis

“…Removal of the trapped compounds from the phase(s) onto the GC column involves heating of the TD tube in a gas flow, and sometimes further concentration is possible using an in-line focusing trap. TD has been applied to a number of dairy products [85,147], milk powder [148], and IMF [149]. A number of application notes are also available on the use of TD [150][151][152].…”