Research background. This study fulfils a need for investigation of a quality profile of snail fillets. Edible snails are a famous food product consumed worldwide and treated as delicacy. Nutritional value, colour and textural properties, such as hardness, are critical factors that impact consumer acceptance of the product. Hardness of snail meat is affected by its native original microstructure. Experimental approach. Fresh snails of the farmed species Cornu aspersum maximum, wild and farmed Cornu aspersum aspersum and wild Helix lucorum were used in order to investigate the qualitative profile of snail meat. Proximate composition, hardness and colour measurements were conducted on fillets of all species. The histological structure of the fillets of Cornu aspersum maximum was examined. Results and conclusions. Quality parameters of snail fillets were studied. A novel method of hardness analysis was proposed where the cylindrical part of snail fillets from the mid-posterior region with specific geometry 6 mm diameter and 6 mm height was used. The suitability of the mid-posterior region was enhanced by the uniform structure confirmed by the histological analysis. Helix lucorum snail fillet had the highest energy content and the highest hardness but the lowest carbohydrate content. The species Cornu aspersum maximum was evaluated with the highest values of a* (redness), b* (yellowness) and C* (chroma) compared to other species. Parameter L* (lightness) of wild snail fillets was lower than of the farmed ones due to age, diet, farming or environmental conditions, but it could also be related to snail carbohydrate content. Novelty and scientific contribution. This study yielded notable results on qualitative characteristics of snail fillets as food and important information is given on its meat properties. Furthermore, a novel methodology of hardness is provided in order to minimize natural, breeding and environmental influences. Finally, the research outcomes could lead to proper handling methods for further fabrication of snail meat.

The edible water frog Pelophylax epeiroticus, distributed mainly in Northwest Greece and utilized commercially as food, was investigated in lake Pamvotida (Ioannina). The objective was to assess aspects of population structure (sex ratio, morphometric characteristics, allometric relationships) and proximate composition of the Epirus water frog (Pelophylax epeiroticus). Commercial samples (31 females and 54 males) were obtained and sex ratio, morphometric characteristics, allometric relationships and proximate composition were assessed. A significantly lower abundance of females was indicated (31 females and 54 males). Body length range was higher in females (females 3.4 mm, males 2.6 mm), whereas total weight range was higher in males (females 45.08 gr, males 48.35 gr). Differences in allometric relationships were indicated between sexes. The high protein (15.93 ± 3.32) and low lipid (0.25 ± 0.13) contents indicated that P. epeiroticus is an excellent food source of high nutritional value. A tree classification algorithm indicated that the principal contributing component for sex classification was dry matter, followed by a proportion of edible flesh and protein content. A predicted future increase in demand for wild-caught individuals requires the use of a suitable management plan, coupled with the development of farming practices aiming to assure the sustainable exploitation of this important resource and alleviate the pressure on its populations.

The subspecies of the species Cornu aspersum, C. a. aspersum, and C. a. maximum are the dominant farmed species in Greece. The morphological and molecular polymorphism of the two aforementioned subspecies has not been studied in depth. In this study, the polymorphism of snails of the two subspecies derived from seven snail farms throughout Greece was studied using morphological and molecular markers. Firstly, the snail samples of both subspecies were categorized in three shell patterns based on shell color and existence of bands. The conducted population structure analysis revealed three major clusters among the farmed snail populations. As concerns genetic diversity, six loci (Ha5, Ha6, Ha8, Ha9, Ha10, and Ha11) were tested for their polymorphism. Genetic variation was reported within populations rather than among populations. Finally, the obtained data highlighted a common gene pool broodstock for snail farms throughout Greece.

In countries where edible snails are a valued food source, improving snail meat quality is a priority. The aim of this study was to evaluate the effects of grape marc (GM) supplementation in the diet of Cornu aspersum maximum, relative to production performance, animal health and quality of snail meat. GM was added in feed for snails at an inclusion rate of 0%, 7% and 14%. The results demonstrated that GM supplementation can be included in the diet of farmed snails, resulting in a slight increase in feed intake without compromising growth performance. The inclusion of GM in the diet reduces from 2480 EPG (parasites’ eggs per gram of feces) after a non-enriched diet, compared to 700 EPG in the feces of snail fed supplemented diets. Nutritionally, the highest dry matter (24.14%) was observed after 14% feed enrichment. Feed enrichment improved the tenderness of boiled fillets (close to 6 N), with no color changes. Enriched diet may lead to the production of functional food which fulfils consumers’ demands for high-quality products. Notably, this was the first study that used GM as a feed component in heliciculture, highlighting its potential as an alternative and sustainable dietary source.

Aim: This study aimed to evaluate the effects of essential oil nanoemulsion-enriched diets on feed acceptability, growth performance, proximate composition, and digestive gland histology of farmed Cornu aspersum maximum. Methods: A total of 2,000 juvenile snails were divided into four dietary treatments for a two-month feeding experiment. The control group received a commercial poultry feed, while the experimental groups were fed the same diet supplemented with an essential oil nanoemulsion at concentrations of 1 mL/kg (T1), 3 mL/kg (T2), and 5 mL/kg (T3). Eight samplings were conducted to measure snail diameter, weight, mortality, and feed residues. At the end of the experiment, fillet proximate composition and histopathological alterations of the digestive gland tissue were evaluated. Results: A tendency toward increased snail weight was observed across all treatments. Diet enrichment led to significantly higher fillet protein content across all treatment groups (T1, T2, and T3) compared to the control, while lipid content was highest in T1. Histopathological examination revealed enlargement of hepatic ducts in T1, apoptosis of digestive cells in T2, and necrosis of digestive and calcium cells along with thinned epithelium lining in T3. Conclusions: Dietary supplementation with essential oil nanoemulsion did not negatively affect snail growth and resulted in heavier snails with increased fillet protein content. However, histopathological evidence of toxicity rendered higher supplementation levels (T2 and T3) unsuitable. Enrichment at 1 mL/kg appears to be suitable for use in commercial snail farming.

This study investigates the effects of species, geographical origin, and processing on the proximate composition of frog leg meat, with a focus on developing predictive models for processing status. Data were systematically compiled from 18 published studies, yielding 32 entries across 10 edible frog species and multiple processing methods. Proximate composition parameters (moisture, protein, fat, ash) were compared between processed and unprocessed samples, and classification models were trained using moisture content as the primary predictor. Logistic regression and several machine learning algorithms, including Stochastic Gradient Descent, Support Vector Machine, Random Forest, and Decision Tree, were benchmarked under a Leave-One-Study-Out (LOSO) cross-validation framework. Results demonstrated that moisture content alone was sufficient to accurately distinguish processing status, with a critical threshold of ~73% separating processed from unprocessed frog legs. Logistic regression achieved perfect specificity and precision (100%) with an overall accuracy of 96.8%, while other classifiers also performed strongly (>90% accuracy). These findings confirm moisture as a species- and origin-independent marker of processing, offering a simple, rapid, and cost-effective tool for authenticity verification and quality control in frog meat and potentially other niche protein products. Future work should expand sample coverage, validate thresholds across processing types, and integrate biochemical and sensory quality assessments.