Impact of composition and aeration on the migration of TAGs in sandwich type confectionery products.

A sandwich type confectionery product is made with a soft filling and a chocolate coating. The fats used for these two parts are generally different to provide specific organoleptic sensations. Thus, their compositions, in terms of the triacylglycerols (TAGs) profile, are different. Depending on the ambient temperature conditions, the chemical potential gradient at the interface for TAGs, and the microstructures in the bulk of two parts, the migration of TAGs is influenced. We have studied the impact of different filling recipes on the migration of specific TAGs from the filling to the coating and vice versa with a newly developed tool, referred to as lipstick method. Also, the influence of the micro-aeration of the filling on the transfer process is evaluated. Furthermore, Fick's law of diffusion-based model is developed. The migration of TAGs as predicted by the model is compared to the experimental measurements, and limitations of the model are discussed. This approach can be used to tune the recipes of coating and filling to enhance the shelf-life stability of such products while delivering on specific liking attributes of taste.

Stability to oxidation and interfacial behavior at the air/water interface of minimally-processed versus processed walnut oil-bodies.

Oil bodies (OB), the form of triacylglycerol storage in seeds, are interesting natural assemblies for nutritional applications. In walnuts, OB contain an important amount of polyunsaturated fatty acids that could be interesting food ingredients but may be prone to oxidation. The oxidative and interfacial behavior of walnut OB, either minimally-processed or after processing, were compared with processed complex walnut juice. The good oxidative stability of minimally-processed OB over 10 days (PV ≤ 8.4 meq O2/kg, TBARS = 1.4 mmol eq MDA/kg) and of processed walnut complex matrixes over 20 days (PV ≤ 4.8 meq O2/kg, TBARS = 1.4 mmol eq MDA/kg) was evidenced. In comparison, processing of OB promoted their oxidation. The interfacial studies led to the proposition of a new model of adsorption for minimally-processed OB that will be useful to design functional emulsion or foam in which OB act as emulsifiers.

Analysis of Oxidative Carbonyl Compounds by UPLC-High-Resolution Mass Spectrometry in Milk Powder.

Long-chain polyunsaturated fatty acids are highly susceptible to lipid oxidation which causes undesirable odors and flavors in food. We present the development, validation, and application of a semiquantitative screening method to monitor volatile and nonvolatile carbonyl compounds generated from lipids oxidation after 7-(diethylamino)-2-oxochromene-3-carbohydrazide (CHH) derivatization using liquid chromatography high-resolution mass spectrometry. An inclusion list containing eligible compounds was used in full scan mode to identify potential oxidative markers. In an antioxidants study using lecithin and tocopherols, the proposed method was successfully used to monitor the docosahexaenoic acid (DHA)-specific oxidative markers in a model milk powder system enriched with fish oils. The results showed that lecithin inhibits oxidation by reducing the peroxidation rate, while δ-tocopherol delays the oxidation with distinct induction periods. Here, we explore the optimum concentration of soy lecithin and δ-tocopherol needed to limit lipid oxidation in a complex food matrix such as milk powder.

Mapping the regioisomeric distribution of fatty acids in triacylglycerols by hybrid mass spectrometry.

This study describes the use of hybrid mass spectrometry for the mapping, identification, and semi-quantitation of triacylglycerol regioisomers in fats and oils. The identification was performed based on the accurate mass and fragmentation pattern obtained by data-dependent fragmentation. Quantitation was based on the high-resolution ion chromatograms, and relative proportion of sn-1(3)/sn-2 regioisomers was calculated based on generalized fragmentation models and the relative intensities observed in the product ion spectra. The key performance features of the developed method are inter-batch mass accuracy < 1 ppm (n = 10); lower limit of detection (triggering threshold) 0.1 µg/ml (equivalent to 0.2 weight % in oil); lower limit of quantitation 0.2 µg/ml (equivalent to 0.4 weight % in oil); peak area precision 6.5% at 2 µg/ml concentration and 15% at 0.2 µM concentration; inter-batch precision of fragment intensities < 1% (n = 10) independent of the investigated concentration; and averaged accuracy using the generic calibration 3.8% in the 1-10 µg/ml range and varies between 1-23% depending on analytes. Inter-esterified fat, beef tallow, pork lard, and butter fat samples were used to show how well regioisomeric distribution of palmitic acid can be captured by this method.