With the global population projected to reach nine billion by 2050, the search for alternative protein sources has become critical. This study evaluated the digestibility of cricket protein powder compared with that of whey protein powder. Cricket protein powder had a slightly lower protein content but higher fat content than whey protein powder. Although both contained all essential amino acids, their quantities varied. The most abundant essential amino acid was leucine in both samples. The essential amino acid index (EAAI) for cricket protein powder reached 79% when utilising crude protein for calculation. When using the amino acid sum calculation method, it increased by nearly 13%. The EAAI for whey protein was then 94% when calculated based on crude protein, with a slight increase observed when using the amino acid sum calculation method. Cricket protein exhibited a gradual increase in digestibility during intestinal digestion, reaching nearly 80%, whereas whey protein digestibility surpassed 97%. Despite the lower digestibility of cricket protein compared with whey protein, it remains sufficiently high for consideration as a valuable protein source. This study highlights the potential of cricket proteins and underscores the importance of assessing their protein content and digestibility in evaluating their nutritional value.

Fish are a valuable source of high-quality protein and essential nutrients, making them an integral component of a healthy diet. However, protein digestibility, influenced by preparation methods, is a critical factor in assessing nutritional quality. This study aimed to evaluate the impact of various thermal processing methods on the protein digestibility of two commonly consumed small pelagic fish species: sardines (Sardina pilchardus) and sprats (Sprattus sprattus). Protein digestibility was assessed using two complementary approaches: total protein digestibility and the Digestible Indispensable Amino Acid Score (DIAAS). Fish samples were subjected to different cooking methods, including boiling, steaming, baking, and frying. All thermal treatments enhanced protein digestibility compared to raw fish. Fried samples exhibited the highest total protein digestibility, with sardines reaching 92.4 ± 4.3% and sprats reaching 89.5 ± 4.4%. DIAAS values corroborated these findings, indicating superior protein quality in fried fish. While frying yielded the highest digestibility scores, steaming and boiling provided a favourable balance between improved protein quality and lower potential health risks, with baking achieving comparable results.

Background: Flaxseed (Linum usitatissimum L.) represents a unique source of bioactive compounds with demonstrated health benefits. The main aim of the research was to investigate the chemical composition, content of bioactive compounds and biological activities of various types of flaxseed and their defatted forms. Methods: Proximate composition (crude fat, protein, ash, digestible carbohydrates, fiber) was determined, and fatty acid profiles were analyzed via GC-MS (gas chromatography–mass spectrometry). Mineral content was measured by atomic absorption spectrometry, while total and individual polyphenols were quantified spectrophotometrically and by HPLC (high-performance liquid chromatography). Antioxidant activity was assessed using three assays. In vitro functional assays evaluated the effects of flaxseed extracts on lactic acid bacteria adhesion in two cellular models, nitric oxide production in liposaccharide (LPS)-stimulated RAW 264.7 macrophages, proliferation and apoptosis of MCF-7 breast cancer cells. Results: Significant differences (p ≤ 0.05) were observed in the proximate composition: brown flaxseed exhibited the highest crude fat content, whereas defatted seeds had higher levels of digestible carbohydrates and ash. α-Linolenic acid was the dominant fatty acid, with the highest concentration in defatted golden flaxseed. Defatted forms generally displayed increased mineral concentrations, particularly calcium, magnesium, potassium, and iron. The polyphenolic content and antioxidant activity were highest in defatted brown flaxseed, which also exhibited the greatest diversity of individual polyphenols. Flaxseed extracts modulated the adhesion of lactic acid bacteria, reduced the production of nitric oxide in RAW 264.7 macrophages, inhibited the proliferation of MCF-7 breast cancer cells in a dose- and time-dependent manner, and induced apoptosis of the mentioned cells. Conclusions: Flaxseed, especially the brown type, could be a promising source of bioactive compounds with antioxidant, anti-inflammatory and anticancer potential, supporting its use in nutritional and functional applications.

Mercury studies in fish are largely based on muscle tissue, while the effects of household cooking on mercury speciation in whole small pelagic fish remain insufficiently understood. To address this gap, total mercury (T-Hg), methylmercury (MeHg), and Hg(II) were determined in wet whole-fish homogenates, including viscera, of sardines and sprats before and after boiling, steaming, baking, and frying. T-Hg was determined by AMA-254 and mercury species by HPLC-ICP-MS; results were expressed on wet-weight (ww), dry-weight (dw), and 100 g reference-portion bases. Frying yielded the highest dry matter, underscoring moisture-related differences among reporting bases. T-Hg concentrations ranged from 0.0518 to 0.1322 µg/g dw and MeHg from 0.0273 to 0.0624 µg/g dw. MeHg was detected in all samples, whereas Hg(II) exceeded the method detection limit only in baked and steamed sardines. MeHg amounts per 100 g ranged from 1.38 to 2.35 µg in sardines and from 0.95 to 1.79 µg in sprats. Within the tested batch, no treatment consistently reduced T-Hg or MeHg across both species. By combining whole-fish analysis, including viscera, with direct mercury speciation and multiple reporting bases, this study provides a food-relevant framework for interpreting mercury in processed small pelagic fish.

The effects of household cooking on mercury speciation in whole small pelagic fish remain insufficiently understood. To address this gap, total mercury (T-Hg), methylmercury (MeHg), and Hg(II) were determined in wet whole-fish homogenates, including viscera, of sardines and sprats before and after boiling, steaming, baking, and frying. T-Hg was determined by AMA-254 and mercury species by HPLC-ICP-MS; results were expressed on wet-weight (ww), dry-weight (dw), and 100 g reference-portion bases. Frying yielded the highest dry matter, underscoring moisture-related differences among reporting bases. T-Hg concentrations ranged from 0.0518 to 0.1322 µg/g dw and MeHg from 0.0273 to 0.0624 µg/g dw. MeHg was detected in all samples, whereas Hg(II) exceeded the method detection limit only in baked and steamed sardines. MeHg amounts per 100 g ranged from 1.38 to 2.35 µg in sardines and from 0.95 to 1.79 µg in sprats. Within the tested batch, no treatment consistently reduced T-Hg or MeHg across both species. By combining analysis of the complete fish matrix with direct mercury speciation and multiple reporting bases, this study provides a food-relevant framework for interpreting mercury in processed small pelagic fish.

Small pelagic fish are nutrient-dense foods, but whether domestic cooking alters their capacity to modulate probiotic adhesion is unclear. We prepared sardines and sprats using five household techniques (raw, cooked, steamed, baked, and fried) and generated in vitro digestates using the INFOGEST method. We tested two concentrations in two intestinal co-cultures—Caco-2/HT29 and mucin-producing Caco-2/HT29-MTX. Adhesion of Lacticaseibacillus rhamnosus, Lactobacillus gasseri, and Lactobacillus brevis were quantified. Digestates altered adhesion in a probiotic strain species in a process-dependent manner. Sprat digestates from fried or baked preparations produced the strongest stimulation, exceeding 150% in Caco-2/HT29; responses in HT29-MTX were directionally similar but attenuated. In contrast, cooked or steamed sardine digestates frequently inhibited adhesion, particularly at 0.5% (e.g., L. gasseri < 50%). Raw preparations yielded divergent outcomes across models. A two-way ANOVA confirmed significant effects of processing, concentration, and their interaction, with the interaction explaining up to 21% of the observed variance. Across conditions, L. rhamnosus adhered most consistently, whereas L. brevis and L. gasseri were more environmentally sensitive. These findings suggest that standard cooking practices alter the bioactivity of fish-derived digestates and, consequently, the adhesion of beneficial lactobacilli in intestinal cell models, selecting sprats and employing dry-heat methods may favor probiotic–host interactions under in vitro conditions.