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Abstract

The fatty acid compositions of both lipid classes, triglycerides (TG) and phospholipids (PL), of caviar from 34 specimens of wild caught and 12 farmed specimens were measured. The investigated caviar samples of wild caught sturgeon comprised Huso huso, Acipenser gueldenstaedti, Acipenser stellatus and Polyodon spathula of different origins and those of farmed sturgeon from Acipenser baeri, A. stellatus, and P. spathula. Oleic acid (18 : 1 n–9) was the dominant fatty acid in TG of all caviar samples. In comparison with the TG, the PL have an elevated content of polyunsaturated fatty acids such as arachidonic (20 : 4 n–6), eicosapentaenoic (20 : 5–3) and docosahexaenoic acid (22 : 6 n–3). In the TG were observed some differences in the fatty acid composition between the caviar samples of the various species, especially in 18 : 1 n–9 and 20.5–3 but not in the PL. The proportion of n–3 to n–6 polyunsaturated fatty acids (PUFAs) was independent from the fish species and origins and did not reveal significant differences. The amount of n–3 PUFAs was in average three times higher compared to n–6 PUFAs. However, the fatty acid composition of the caviar depends on the origin of the sample, probably caused by differences in the food web. The caviar of farmed sturgeon contained a significant higher amount of linoleic acid (18 : 2 n–6) and a lower amount of arachidonic acid, when compared with caviar from wild sturgeon. An explanation could be that sturgeon are not able to convert 18:2 n–6 into 20 : 4 n–6.

Sturgeon Meat and Caviar Quality from Different Cultured Species

“…The fatty acids profile detected in our samples matched with the general pattern reported in literature for fatty acid composition of sturgeon eggs and caviar [7,10,12,13,[19][20][21]. Among the saturated fatty acids (SFA), palmitic acid (16:0) proved to be the most abundant in both eggs and caviar samples, regardless of the species considered, according to the results of several previous publications [7,9,10,12,22].…”

“…As well as for LA, the level of ARA in caviar depends on the feed source supplied to sturgeons. Although ARA is the second most predominant among the n6 PUFA, our results showed significantly lower amounts than what is described in literature for wild caviar [9,11,19,24]. This can be imputed to the fact that ARA is highly present inside the aquatic trophic chains, especially in some algae and in some crustaceans [25] that represent the natural diet sources of wild sturgeons.…”

“…In both cases, significant differences were observed among the different species under investigation. The high content of LA in sturgeon eggs and caviar is supported by literature data, which show a high percentage of linoleic acid (significantly greater than in wild samples) in caviar from cultured sturgeon, mainly due to the lipid composition of commercial diets [7,[9][10][11]19,24]. It is well known that linoleic acid is widely represented in oils of vegetable origin (such as soy oil, sunflower oil, rapeseed oil, corn oil) commonly used in commercial feed as an alternative lipid source, to partial replacement of fish oils, more expensive and less eco-sustainable.…”

Fatty acid composition and volatile compounds of caviar from farmed white sturgeon (Acipenser transmontanus)

“…It has been reported that in eggs, during gametogenesis, lipoprotein biosynthesis preferentially utilises saturated and monounsaturated fatty acid from adipose and muscle tissues to provide metabolic energy, while n-3 PUFA are incorporated into phospholipids fraction of vitellogen and transferred via the serum into the eggs [34].…”

Volatile Organic Compounds Profile in White Sturgeon (Acipenser transmontanus) Caviar at Different Stages of Ripening by Multiple Headspace Solid Phase Microextraction

“…For instance, DNA testing, based on genetic interspecific divergences and variations, is a well-known technique used to verify the species source of the product to date [4][5][6], even if the presence of hybrid sturgeons could make it difficult to correctly attribute a caviar to a single species. Moreover, it has been demonstrated that the chemical composition of caviar can lead to discriminate, above all, between eggs obtained from farmed vs. wild sturgeons [7][8][9] or eggs coming from different species [10].…”