This study was carried out on 96 caged Bovans Brown laying hens at an initial age of 25 weeks, which were randomly assigned to four experimental groups of 12 replicates (cages) of two hens per cage. The control group hens received a diet containing 20% soybean meal (SBM), without Hermetia illucens larvae meal (HIM) content. The hens in the experimental groups received a diet containing defatted HIM at levels of 5, 10, and 15% (HIM 5%, HIM 10%, and HIM 15%, respectively), at the expense of a proportionally decreasing content of SBM. During the 12-week experiment, the laying performance, biochemical and redox blood indices, and liver condition were examined. The cholesterol level, fatty acid profile, and malondialdehyde content in egg yolks were also evaluated to determine the dietary quality of the eggs. The inclusion of HIM at any level in the diet did not affect the laying performance parameters (p > 0.05). Increased serum Ca and uric acid contents were observed. There was no effect on the redox indices in plasma. The number of hepatocytes was decreased in the HIM-fed groups. The level of cholesterol in yolks was reduced, and the fatty acid profile showed significant changes. Despite the high lauric acid content in the H. illucens meal, it was present in trace amounts in yolks. In the HIM-fed groups, the levels of saturated fatty acids increased significantly, whereas those of unsaturated fatty acids decreased in the yolks in the same groups.

The aim of this study was to assess the changes occurring as a result of boiling (100°C, 1 h) small brown snail ( Cornu aspersum aspersum ) meat in relation to its proximate composition, calcium, phosphorus and cholesterol content, as well as the profile of fatty acids and nutritional quality indices of the lipids. This species of snail was selected for research because it is currently of the greatest economic importance among edible terrestrial snails. It was hypothesized that the cooking effect may be different for foot and visceral sac. Samples for the research were collected from 6 populations bred on experimental fields of the National Research Institute of Animal Production in balice (Poland). The foot and the visceral sac, the edible parts of the snail species under investigation, were analysed separately, raw and boiled in water. The results were then compared to analogous studies carried out by other authors on beef, pork and poultry. It was found that in the visceral sac of Cornu aspersum aspersum the shares of dry matter, crude protein, fat, ash, calcium and phosphorus were greater than those in the foot (P<0.05), both in the raw and boiled material, whereas the cholesterol content was higher in the foot (P<0.05). Generally, especially in the foot, the heat treatment elevated the levels of the afore-mentioned quantities, yet the increases were not always statistically significant. Boiling the snail meat caused moderate changes in the fatty acid composition. The profile of the fatty acids and the nutritional quality indices of the foot fat were more advantageous than those in the visceral sac. In both parts of the snail carcass, the polyunsaturated fatty acids/saturated fatty acids (PUFA/SFA) ratio substantially exceeded the minimum value of 0.45 recommended by the British Department of Health. However, the n-6/n-3 ratio was too high, exceeding the maximum recommended level of 4.0 twofold and as much as threefold in the case of the foot and the visceral sac, respectively. In the foot, due to boiling, an increase of the share of sfa and monounsaturated fatty acids (MUFA) was observed, while PUFA, n-6 and n-3 decreased. In the visceral sac, the changes were less pronounced with a slight decrease of the share of sfa and PUFA, and an increase of MUFA. Therefore, in the foot, boiling worsened the PUFA/SFA ratio, the nutritive value index (NVI = (C18:0 + C18:1) / C16:0) and dietary fatty acids having a desirable neutral and hypocholesterolemic effect in humans (DFA = Σ MUFA + Σ PUFA + C18:0), but in the visceral sac these indices practically did not change. On the whole, the trends of the changes in terms of chemical composition due to boiling found in the small brown snail meat are similar to those after heat treatment of meat from popular farm animals, but the ranges of the changes differ.

The aim of this study was to investigate and confirm the properties of eggs produced by laying hens fed a diet consisting of pomegranate seed oil as a source of CLnA and flaxseed oil as a source of α-linolenic acid. The study involved determining the chemical composition of the eggs, including their fatty acid profile. The results showed that modifying the laying hens’ feed composition resulted in eggs with high nutritional value, with a favorable change in their fatty acid profile. In most cases, the addition of linseed oil or pomegranate seed oil did not affect the physical and chemical properties of the eggs. However, the diet of laying hens had a positive effect on the fatty acid profile of the egg yolk. The presence of conjugated linolenic acid trienes in eggs produced by laying hens fed a modified diet makes them a potential source of these compounds for human consumption.

This study aimed to verify that enriching hens’ diets with pomegranate seed (PSO) and linseed oils (LSO) would maintain egg foaming and leavening capacity and improve the nutritional profile of egg-based products without compromising technological properties. It was shown in the previous studies that fortifying hen feed with PSO increased CLnA and CLA concentrations in raw eggs. In this study, two experiments with 25-week-old Hy-Line Brown laying hens have been carried out. Experiment 1 modified hens’ feed by incorporating PSO (0.5–1.5%) and 1.5% LSO. In Experiment 2, hens received feed containing PSO (0.5–1.5%). This research involved cake preparation, quality evaluation, and the assessment of egg white foam properties (stability, density, and gas bubble distribution). The chemical composition of sponge cake was determined. Results showed that PSO and LSO in hen feed enhanced egg leavening properties, while egg white-based foam properties matched the control group. The cakes showed improved health-promoting properties due to CLA and CLnA presence. The research confirmed that these beneficial acids were retained in the final sponge cake.