Combination of sugar analysis and stable isotope ratio mass spectrometry to detect the use of artificial sugars in royal jelly production

Abstract

The effects of feeding bees artificial sugars and/or proteins on the sugar compositions and (13)C isotopic measurements of royal jellies (RJs) were evaluated. The sugars fed to the bees were two C4 sugars (cane sugar and maize hydrolysate), two C3 sugars (sugar beet, cereal starch hydrolysate), and honey. The proteins fed to them were pollen, soybean, and yeast powder proteins. To evaluate the influence of the sugar and/or protein feeding over time, samples were collected during six consecutive harvests. (13)C isotopic ratio measurements of natural RJs gave values of around -25 ‰, which were also seen for RJs obtained when the bees were fed honey or C3 sugars. However, the RJs obtained when the bees were fed cane sugar or corn hydrolysate (regardless of whether they were also fed proteins) gave values of up to -17 ‰. Sugar content analysis revealed that the composition of maltose, maltotriose, sucrose, and erlose varied significantly over time in accordance with the composition of the syrup fed to the bees. When corn and cereal starch hydrolysates were fed to the bees, the maltose and maltotriose contents of the RJs increased up to 5.0 and 1.3 %, respectively, compared to the levels seen in authentic samples (i.e., samples obtained when the bees were fed natural food: honey and pollen) that were inferior to 0.2% and not detected, respectively. The sucrose and erlose contents of natural RJs were around 0.2 %, whereas those in RJs obtained when the bees were fed cane or beet sugar were as much as 4.0 and 1.3 %, respectively. The combination of sugar analysis and (13)C isotopic ratio measurements represents a very efficient analytical methodology for detecting (from early harvests onward) the use of C4 and C3 artificial sugars in the production of RJ.

Antioxidant Potential of Propolis, Bee Pollen, and Royal Jelly: Possible Medical Application

“…Fructose and glucose together account for 90% of all sugars [ 99 , 104 ]. Sucrose is always present but often in variable concentrations (2.86% according to Kanelis et al [ 99 ], 2.1% according to Kolayli et al [ 23 ], 0.5–2% according to Oršolić [ 105 ], and 0.2% according to Wytrychowski [ 106 ]). Studies have also revealed the presence of other oligosaccharides, such as trehalose, maltose, gentiobiose, isomaltose, raffinose, erlose, and melezitose [ 103 , 104 ].…”

Investigating the Effect of Supplementary Feeding on Carbohydrate Composition and Quantity of Royal Jelly

“…Not only the storage conditions but also the beekeeping practices are mentioned to affect RJ's carbohydrate composition [18]. Yet, the scientific findings do not clarify whether feeding affects the chemical synthesis of the product because some authors claim that it causes changes [19] [20] [21] and some others that it does not [22] [23]. Beekeepers believe that the feeding of bees during RJ production, stimulate workers to increase the quantity of RJ [20] [21] but this notion has not been scientifically proved [21].…”

Authentication of the origin of sucrose-based sugar products using quantitative natural abundance13C NMR

“…Previous applications of IR‐NMR for saccharides were mainly devoted to detection of the addition of exogenous sugars from C 4 and C 3 plants in food products such as honey, royal jelly or maple syrup . An IR‐ 13 C NMR analytical method is available to differentiate between sugars from C 4 metabolism plants (cane, maize) and some crassulacean acid metabolism plants (e.g.…”

“…A similar limit of about 15% was found for the adulteration of pineapple juice with cane and maize sugar by IR-13 C NMR. 26 The method is therefore not able to detect slight unintended contamination during the sugar production process, but is sufficient to reveal deliberate adulteration.…”