Chemical characterization and DNA tracking of Sardinian botargo by Mugil cephalus from different geographical origins

Stable Isotope Analysis for the Discrimination of the Geographical Origin of Greek Bottarga ‘Avgotaracho Messolongiou’: A Preliminary Research

Consumers are increasingly interested in the geographical origin of the foodstuff they consume as an important characteristic of food authenticity and quality. To assure the authenticity of the geographical origin, various methods have been proposed. Stable isotope analysis is a method that has been extensively used for products such as wine, oil, meat, while only a few studies have been conducted for the discrimination of seafood origin and especially for mullet roes or bottarga products. Analysis of the stable isotopes of C, N and S of Bottarga samples from four different origins were carried out. The values of δ¹⁵N (5.45‰) and δ³⁴S (4.66‰) for the Greek Bottarga Product named ‘Avgotaracho Messolongiou’, from Messolongi lagoon were lower than other areas while δ¹³C values were higher (−14.84‰). The first results show that the stable isotopes ratios of carbon, nitrogen and sulphur could be used to discriminate the Greek Protected Designations of Origin Bottarga product ‘Avgotaracho Messolongiou’ from other similar products.

Influence of the Technological Process on the Biochemical Composition of Fresh Roe and Bottarga from Liza ramada and Mugil cephalus

Bottarga is a high-priced delicacy with high nutritional value, and, in Italy, bottarga from mullets has been recognized to be a traditional food product. The flathead grey mullet Mugil cephalus and the thinlip grey mullet Liza ramada are the main cultured grey mullets in the Mediterranean Sea. In this study, fresh roe and bottarga from these two species were investigated to evaluate the influence of the technological process and the species on their biochemical composition and health advantages. The 1 h/200 g salting-out step did not increase the levels of NaCl in the bottarga, although it highly decreased the levels of some heavy metals like Cu and Al. Processing of fresh roe in bottarga led to an essential modification of the lipid fraction, following a general series of monousatturated fatty acid (MUFA)> poliunsutturated fatti acid (PUFA) > saturated fatty acid (SAFA) and an increase in both ω3 and ω6 in Liza ramada. Moreover, bottarga showed higher levels of squalene and cholesterol and an increased Essential Amino Acid/Total Amino Acid ratio (EAA/TAA) in both species. In addition to the nutritional benefits for the consumer, the process proposed in this study may represent a reliable tool for local producers to obtain a final bottarga with both a reproducible biochemical composition and organoleptic characteristics.

A case study on the labeling of bottarga produced in Sardinia from ovaries of grey mullets (Mugil cephalus and Mugil capurrii) caught in Eastern Central Atlantic coasts

The aim of this case study is to show how traditional and molecular methods can be employed to identify the Mugilidae species currently used in Sardinia (Italy) to produce the traditional bottarga for the processing of their ovaries. A total of six specimens of Mugil cephalus (n=3) and Mugil capurrii (n=3) were subjected to external morphology and meristic measurements. Subsequently, tissue samples of white muscle and ovaries from three individuals per species were underwent PCR-sequencing assay of mitochondrial DNA cytochrome oxidase subunit I (COI). The external morphology and meristic characters showed a sufficient level of reliability in the identification between the two species. At the same time, the molecular techniques showed the discriminatory power and confirmed the correct species identification in all the sampling units. DNA barcoding may be an effective aid to traditional taxonomy and can facilitate accurate species identification among the Mugilidae.

Evaluation of the Physicochemical Parameters of Functional Whey Beverages

The objective of this study is to determine the impact of the key technological parameters on the quality indices of functional beverages produced from whey and enriched with 0.2% of cold-pressed flaxseed oil, rich in ω-3 fatty acids. The amount of fatty acids, peroxide and anisidine values, fatty acidity, sedimentation and sensory parameters of whey beverages were estimated. It was found that the addition of flaxseed oil affected the sensory, physical and chemical properties of the beverages. High quantities of oleic and α-linolenic fatty acids (18.97 and 54.82%, respectively) and negligible amounts of palmitic and myristic acids (4.79 and 0.04%, respectively) were found in the product. On the basis of the obtained results, the beverages from whey enriched with flaxseed oil had a favourable ratio of n-6/n-3 polyunsaturated fatty acids and atherogenic and thrombogenic indices. The addition of a stabiliser and the pasteurisation of whey beverages with flaxseed oil did not affect the sensory parameters and the acidity of the products. The highest peroxide value (2.36 meq O₂/kg) and acidity (0.34%) were found in the samples with pH=4.0 after 30-day storage at (6±1) °С. A strong negative correlation was estimated between the amount of polyunsaturated fatty acids and anisidine value (R=-0.871; p<0.05), peroxide value (R=-0.728; p<0.05) and fatty acidity (R=-0.948; p<0.05).