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COMPARAÇÃO DO LIMITE DE ESCOAMENTO DO CHOCOLATE CONTENDO APENAS LECITINA COM CHOCOLATE CONTENDO LECITINA E PGPR AO FINAL DA TEMPERAGEM
Source publication
The objective of this study was to evaluate the rheological behavior of dark chocolates varying lecithin and polyricinoleate polyglycerol (PGPR) levels. Samples of chocolate were prepared adding 0.3 to 1.4% (w/w) lecithin and a combination of lecithin/PGPR. In these last experiments PGPR was kept constant at 0.2% and lecithin varied from 0.3, 0.5 a...
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Citations
... These emulsions are either used as such, for example as low fat spreads or are used in the production of double emulsions (W/O/W emulsions) for potential food applications Clegg et al. 1996;Balcaen et al. 2017;Rebry et al. 2020). In addition, PGPR can be applied in chocolate products, particularly for improving the moulding properties, increasing the tolerance to the thickening effect and limiting fat bloom (Lonchampt and Hartel 2004;Peschar et al. 2004;Schenk and Peschar 2004;Da Cunha et al. 2010). In order to enforce the specified legal restrictions, analytical methods should be available enabling to determine the actual PGPR content in foods. ...
Polyglycerol polyricinoleate (PGPR) is a powerful lipophilic emulsifier used in low-fat spreads and chocolate. It should be used at the lowest level at which the desired technological effect is achieved, not exceeding the specified maxima according to Annexe II to Regulation (EC) No 1333/2008. A gas chromatography–flame ionisation detection (GC-FID) method was developed for quantification of PGPR. This method is based on estimating the content of ricinoleic acid using 12-hydroxyoctadecanoic acid as an internal standard, from which the PGPR concentration was deduced. The method involved saponification, methylation, a two-step solid phase extraction (SPE) separation of the fatty acid methyl esters (FAMEs), silylation, and GC-FID analysis. The limits of detection and quantification of ricinoleic acid were 2.2 and 6.7 μg/mL, respectively, at 0.1 µL injection volume. Considering the average content of ricinoleic acid in PGPR (i.e. 86.63 ± 2.0 wt%) and the amount of food product that is used in the proposed protocol (i.e. 20 mg), this resulted in a LOD and LOQ of 0.76 and 2.32 μg PGPR per mg of food product, respectively. The developed method was validated by determining PGPR recovery from a high oleic sunflower oil (HOSO) solution, from chocolate spiked with a commercially available PGPR, and from commercially available low fat spreads with a known PGPR content. The actual recovery was more than 95% for all matrices, indicating the accuracy of the developed analytical technique. Moreover, the method proved to be very reproducible, with RSD < 4% for concentrations ranging from 0.2 to 5 wt%. The results showed that our proposed GC-FID method enables the reliable and quantitative determination of the PGPR concentration in commercial food products with various fat contents.
