Bioactive peptides are short amino acid sequences, that upon release from the parent protein may play different physiological roles, including antioxidant, antihypertensive, antimicrobial, and other bioactivities. They have been identifi ed from a range of foods, including those of animal origin, e.g., milk and muscle sources (with pork, beef, or chicken and various species of fi sh and marine organism). Bioactive peptides are encrypted within the sequence of the parent protein molecule and latent until released and activated by enzymatic proteolysis, e.g. during gastrointestinal digestion or food processing. Bioactive peptides derived from food sources have the potential for incorporation into functional foods and nutraceuticals. The aim of this paper is to present an overview of the muscle-derived bioactive peptides, especially those of fermented meats and the potential benefi ts of these bioactive compounds to human health.

Information on taste‐active components of porcine meat was provided based on an in‐silico analysis using tools available in the BIOPEP database. The role of proteins as crucial nonvolatile components of muscle tissue was defined to develop the sensory profile of meat products. Among them, myofibrillar proteins, particularly myosin‐2, proved to be a good precursor for taste‐active peptides and amino acids; bitter, umami, and sour compounds were the most numerous among them. The role of peptides in suppressing (sourness and sweetness) and enhancing (salty and umami) the taste was also highlighted, which was not observed for amino acids. Troponin T, fast skeletal muscle, was the only source of components suppressing the sour taste. Practical applications The properties of dry‐cured meats may result from the presence of bioactive peptides released by protein hydrolysis during fermentation and aging. However, protein hydrolysates sometimes have a bitter taste, which is unwanted by consumers, thus it is necessary to look for a way to combine functionality with consumer acceptability of food products undergoing proteolytic changes, such as dry‐cured meat products. So far, there is insufficient knowledge regarding the protein factors directly related to porcine raw meat influencing the taste that affects consumer acceptability, commercialization, and validation of functional peptide‐rich products. This analysis is a thorough and useful data source on taste‐active protein compounds in porcine meat that can be used to show what taste can be expected if this particular material is applied to produce some specific meat‐derived product (e.g., dry‐cured meat).

Selected porcine myofibrillar proteins have been assessed as potential precursors of bioactive peptides based on in silico analysis. The potential of protein sequences for releasing peptides was evaluated by determining the profile of their potential biological activity and the frequency of occurrence of fragments with a given activity using the BIOPEP database. Digestive enzymes: pepsin, trypsin and chymotrypsin have been used for the in silico proteolysis with the use of the "Enzyme(s) action" tool in BIOPEP. After simulated gastrointestinal digestion the tested sequences of pig myofibrillar proteins are a potential source of a total of 399 peptides with activities such as enzyme inhibition, antioxidative, hypotensive, stimulating or regulating various body functions and antiamnestic activities. Within the intact proteins and after simulated gastrointestinal digestion, dipeptidyl peptidase IV inhibitory peptide sequences were the most frequently observed. The results indicate that pork myofibrillar proteins are a promising source of peptides with biological activity.

The application of starter cultures to improve quality and safety has become a very common practice in the meat industry. Probiotic strains of lactic acid bacteria (LAB) can also bring health benefits by releasing bioactive peptides. The aim of this work was to evaluate the stability of antiradical activity of protein extracts from LAB-inoculated dry-cured pork loins during long-term aging and evaluate their hydrolysates after simulated gastrointestinal digestion. Analyses of hydrolysates by using liquid chromatography-tandem mass spectrometry (LC-MS/MS) were strengthened with in silico analysis. The highest antiradical activity of the protein extracts was observed after 180 days of aging. The influence of the strain used (LOCK, BAUER, or BB12) on the inactivation ability of ABTS radicals varied during long-term aging. The IC50 values indicated the higher antiradical properties of salt-soluble (SSF) compared to water-soluble fraction (WSF) of proteins. The peptides generated by in vitro digestion have MW between 700 and 4232 Da and their length ranged from 5 to 47 amino acids in a sequence where Leu, Pro, Lys, Glu, and His had the largest share. This study demonstrates that the degradation of pork muscle proteins during gastrointestinal digestion may give rise to a wide variety of peptides with antiradical properties.

This study focuses on collecting actual data on the workable possibility of reducing the technological use of nitrites in beef products according to the present trends in nutrition, especially in terms of European Union (EU) food law. Measurements of safety by technological (pH value, water activity, N-nitrosamine), microbiological, oxidative stability (thiobarbituric acid reactive substances, oxidation-reduction potential), and color parameter (CIE L*a*b*, total heme pigment and heme iron) methods were taken after production and storage. The roasted beef with a reduced inclusion level of sodium nitrite (75 mg/kg and below) was more vulnerable to lipid oxidation. The quantities of primary lipid oxidation products were related to the sodium nitrite inclusion level (50–150 mg/kg). Clostridium spp., Staphylococcus aureus, and Listeria monocytogenes were not detected in any of the samples tested during all the experiments. The total count of Enterobacteriaceae increased with the decrease in sodium nitrite content, from log 2.75 cfu/g at the highest to log 6.03 cfu/g at the smallest addition of nitrite. The obtained results revealed that the addition of 100 mg/kg of sodium nitrite would be adequate for minced roasted beef, without significant unexpected effects on color, oxidative stability, and microbiological safety compared with the control (150 mg/kg).

Summary Selected physico‐chemical and proteolysis‐related parameters were evaluated in dry‐cured loins inoculated with probiotic (Lactobacillus rhamnosus LOCK900, Bifidobacterium animalis subsp. lactis BB12) and potentially probiotic (Lactobacillus acidophilus Bauer Ł0938) lactic acid bacteria (LAB) strains and compared with a control sample at five different storage times (28, 90, 180, 270 and 360 days). Physico‐chemical parameters of dry‐cured loins were significantly (P < 0.01) affected by treatment, storage time and the interaction between them. The count of lactic acid bacteria (LAB) in dry‐cured loins was in accordance with their pH. Higher intensity of proteolysis, as assessed by non‐protein nitrogen content (NPN) and proteolysis index (PI), occurred in inoculated samples. Based on the SDS‐PAGE analysis, the modifications produced during storage on the sarcoplasmic proteins were more pronounced than those exerted on the myofibrillar protein fraction. However, inoculation effect was absent from SDS‐PAGE protein patterns.

The results indicated that bioactive peptides could be generated in uncured roasted beef. The <3.5 kDa peptides have strong antioxidant activity, as a result of which they function as inhibitors of lipid oxidation and colour discoloration during prolonged storage. © 2018 Society of Chemical Industry.

This research investigated the potential of beef products with acid whey to release bioactive peptides and thereby emphasize their health-promoting potential. Peptide sequences were isolated and identified by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). Firstly, the antihealth properties (toxicity, allergenicity) of the peptides were estimated based on the peptide sequences. Next, their health-promoting potential was demonstrated based on an in silico analysis by determining their bioactivity scores (PeptideRanker). Their various biological actions were also determined using BIOPEP-UWM tools. We presented peptide sequences with properties relevant to ensuring good health and well-being, including cardiovascular system, nervous and immune systems, or their support for the maintenance of general homeostasis. We obtained information on generation of biologically active peptides in uncured beef with acid whey and it can be considered as a new knowledge as it contributes to science development of functional and nutraceutical foods. In the long term, this information can be used in designing products with desired nutritional and health-promoting properties that are important for the well-being and for preventing the occurrence of noncommunicable diseases.