Earth worming—An evaluation of earthworm (Eisenia andrei) as an alternative food source

Aside from their bioremediation roles, little is known about the food and feed value of earthworms. In this study, a comprehensive evaluation of the nutritional composition (proximate analysis and profiles of fatty acids and minerals) and techno-functional properties (foaming and emulsion stability and capacity) of earthworm (Eisenia andrei, sourced in New Zealand) powder (EAP) were investigated. Lipid nutritional indices, ω6/ω3, atherogenicity index, thrombogenicity index, hypocholesterolemic/hypercholesterolemic acid ratio, and health-promoting index of EAP lipids are also reported. The protein, fat, and carbohydrate contents of EAP were found to be 53.75%, 19.30%, and 23.26% DW, respectively. The mineral profile obtained for the EAP consisted of 11 essential minerals, 23 non-essential minerals, and 4 heavy metals. The most abundant essential minerals were potassium (8220 mg·kg¯¹ DW), phosphorus (8220 mg·kg¯¹ DW), magnesium (744.7 mg·kg¯¹ DW), calcium (2396.7 mg·kg¯¹ DW), iron (244.7 mg·kg¯¹ DW), and manganese (25.6 mg·kg¯¹ DW). Toxic metals such as vanadium (0.2 mg·kg¯¹ DW), lead (0.2 mg·kg¯¹ DW), cadmium (2.2 mg·kg¯¹ DW), and arsenic (2.3 mg·kg¯¹ DW) were found in EAP, which pose safety considerations. Lauric acid (20.3% FA), myristoleic acid (11.20% FA), and linoleic acid (7.96% FA) were the most abundant saturated, monounsaturated, and polyunsaturated fatty acids, respectively. The lipid nutritional indices, such as IT and ω-6/ω-3, of E. andrei were within limits considered to enhance human health. A protein extract derived from EAP (EAPPE), obtained by alkaline solubilisation and pH precipitation, exhibited an isoelectric pH of ~5. The total essential amino acid content and essential amino acid index of EAPPE were 373.3 mg·g¯¹ and 1.36 mg·g¯¹ protein, respectively. Techno-functional analysis of EAPPE indicated a high foaming capacity (83.3%) and emulsion stability (88.8% after 60 min). Heat coagulation of EAPPE was greater at pH 7.0 (12.6%) compared with pH 5.0 (4.83%), corroborating the pH-solubility profile and relatively high surface hydrophobicity (1061.0). These findings demonstrate the potential of EAP and EAPPE as nutrient-rich and functional ingredients suitable as alternative food and feed material. The presence of heavy metals, however, should be carefully considered

Physicochemical characteristics, techno-functionalities, and amino acid profile of Prionoplus reticularis (Huhu) larvae and pupae protein extracts

The amino acid profile, techno-functionalities (foaming stability/capacity, emulsion stability/capacity, solubility, and coagulation), and physicochemical characteristics (colour, particle size, surface hydrophobicity, Fourier-transform infrared spectroscopy, and differential scanning calorimetry) of protein extracts (PE) obtained from Prionoplus reticularis (Huhu grub) larvae (HLPE) and pupae (HPPE) were investigated. Total essential amino acid contents of 386.7 and 411.7 mg/g protein were observed in HLPE and HPPE, respectively. The essential amino acid index (EAAI) was 3.3 and 3.4 for HLPE and HPPE, respectively, demonstrating their nutritional equivalence. A unique nitrogen-to-protein conversion constant, k, and the corresponding protein content of the extracts were 6.1 and 6.4 and 72.1% and 76.5%, respectively. HLPE (37.1 J/g) had a lower enthalpy than HPPE (54.1 J/g). HPPE (1% w/v) exhibited a foaming capacity of 50.7%, which was higher than that of HLPE (41.7%) at 150 min. The foaming stability was 75.3% for HLPE and 73.1% for HPPE after 120 min. Both protein extracts (1% w/v) had emulsifying capacities that were 96.8% stable after 60 min. Therefore, protein extracts from Huhu larvae and pupae are of a good nutritional quality (based on their EAAI) and have techno-functional properties, such as foaming and emulsification, that afford them potential for certain food technology applications

Effect of consumption of sheep and cow milk on rat brain fatty acid and phospholipid composition

The effect of sheep milk and cow milk on the lipid composition of rat brain was investigated in two feeding experiments of 28-days duration. Total lipids of the rat brain were extracted using ethanol-hexane, and the fatty acids and phospholipid contents analysed using gas chromatography with flame ionization detection (GC-FID) and phosphorus-31 nuclear magnetic resonance (³¹P NMR). Furthermore, freeze-dried pooled samples were analysed using attenuated total reflectance Fourier Transform Infrared and Fourier Transform Raman Spectroscopy and analysed with multivariate methods. A significantly (P 0.05) differences were observed in the spectroscopy analyses. It is concluded that sheep and cow milks fed to rats for 28-days had a low effect on the brain lipidome

Utilisation of beef lung protein powder as a functional ingredient to enhance protein and iron content of fresh pasta

Beef lungs are an underutilised co‐product of the meat industry that could be used as an ingredient to supplement the protein content of cereal foods. Beef lung powder (BLP) had a protein content of 87% (dry weight basis), an amino acid score of 1, and contained 1 mg g⁻¹ iron. Fresh semolina pasta was used as a model food, and BLP was incorporated up to 20%. Incorporation of 10% BLP improved the indispensable amino acid score of the pasta from 0.48 to 0.91. At that level of incorporation, higher cooking loss and redder (increased ‘a’ value) and darker (decreased ‘L’ value) colour resulted. The fresh pasta with BLP had a lower glycaemic response compared to control samples. BLP improved the functional value of the fresh pasta and is a potential ingredient in the development of new food products

Pulsed electric field operates enzymatically by causing early activation of calpains in beef during ageing

A study was conducted to elucidate the impact of pulsed electric field (PEF) on the activity of calpains, proteolytic activity of desmin and troponin-T and physicochemical properties of beef Biceps femoris during ageing. The meat samples (meat blocks) were subjected to two PEF treatments; T₁ (5 kV, 90 Hz, 0.38 kV/cm) and T₂ (10 kV, 20 Hz, 0.61 kV/cm) and a non-treated control was run in parallel. The samples were vacuum packaged and aged for 1, 7 and 14 days at 4 ± 1 °C. This study reports for the first time the impact of PEF-processing on the calpain activity in beef. Early post-mortem activation of calpain 2 was observed in PEF-treated samples. An increase in the calpain activity and proteolysis of desmin and troponin-T was observed. No significant effect of PEF was observed on the shear force of tough muscles from culled dairy animals during the entire ageing period

The application of pulsed electric field as a sodium reducing strategy for meat products

This study investigated the potential of pulsed electric field (PEF) as a sodium-reduction strategy for processed meat. Beef jerky was used as a model and prepared using different levels of NaCl, viz. 2.0% (control), 1.2% (T₁) and 1.2% along with PEF processing (T₂). A significant (p 0.05) with control and >84% of the panellists preferred T₂ samples over T₁ for saltiness. Results suggest that PEF treatment improved saltiness by influencing the salt diffusion and sodium delivery that led to better perception during chewing. PEF could be a novel method to produce healthier reduced-sodium meat products

Use of fungal and bacterial protease preparations to enhance extraction of lipid from fish roe: Effect on lipidomic profile of extracted oil

The present study investigated the hydrolysis of protein in hoki roe homogenate using a HT (bacterial), a FP-II (fungal) protease preparations and Alcalase (bacterial) to enhance lipid yield extraction. The degree of hydrolysis was determined at various pH, temperature and time using casein and hoki roe. Total lipid extraction and lipidomic analysis was carried out following proteolysis of hoki roe homogenate. The degree of hydrolysis and SDS-PAGE revealed that the hydrolytic capability of Alcalase was better than HT and FPII. The total extracted lipid yield was better following hydrolysis with Alcalase (19.29 %), compared to HT (18.29 %) and FPII (18.33 %). However, the total phospholipid (PL) and n-3 fatty acid yields were better from HT hydrolysed hoki roe homogenate (PL = 30.7 μmol/g; n-3 = 10.5 %), compared to Alcalase (PL = 22 μmol/g; n-3 = 5.95 %). Overall, this study indicates that HT protease preparation hydrolysis of fish roe homogenate can both enhance lipid extraction and retain lipid quality

Marine fish-derived lysophosphatidylcholine: Properties, extraction, quantification, and brain health application

Long-chain omega-3 fatty acids esterified in lysophosphatidylcholine (LPC-omega-3) are the most bioavailable omega-3 fatty acid form and are considered important for brain health. Lysophosphatidylcholine is a hydrolyzed phospholipid that is generated from the action of either phospholipase PLA₁ or PLA₂. There are two types of LPC; 1-LPC (where the omega-3 fatty acid at the sn-2 position is acylated) and 2-LPC (where the omega-3 fatty acid at the sn-1 position is acylated). The 2-LPC type is more highly bioavailable to the brain than the 1-LPC type. Given the biological and health aspects of LPC types, it is important to understand the structure, properties, extraction, quantification, functional role, and effect of the processing of LPC. This review examines various aspects involved in the extraction, characterization, and quantification of LPC. Further, the effects of processing methods on LPC and the potential biological roles of LPC in health and wellbeing are discussed. DHA-rich-LysoPLs, including LPC, can be enzymatically produced using lipases and phospholipases from wide microbial strains, and the highest yields were obtained by Lipozyme RM-IM®, Lipozyme TL-IM®, and Novozym 435®. Terrestrial-based phospholipids generally contain lower levels of long-chain omega-3 PUFAs, and therefore, they are considered less effective in providing the same health benefits as marine-based LPC. Processing (e.g., thermal, fermentation, and freezing) reduces the PL in fish. LPC containing omega-3 PUFA, mainly DHA (C22:6 omega-3) and eicosapentaenoic acid EPA (C20:5 omega-3) play important role in brain development and neuronal cell growth. Additionally, they have been implicated in supporting treatment programs for depression and Alzheimer’s. These activities appear to be facilitated by the acute function of a major facilitator superfamily domain-containing protein 2 (Mfsd2a), expressed in BBB endothelium, as a chief transporter for LPC-DHA uptake to the brain. LPC-based delivery systems also provide the opportunity to improve the properties of some bioactive compounds during storage and absorption. Overall, LPCs have great potential for improving brain health, but their safety and potentially negative effects should also be taken into consideration

Non-thermal processing has an impact on the digestibility of the muscle proteins

Muscle proteins undergo several processes before being ready in a final consumable form. All these processes affect the digestibility of muscle proteins and subsequent release of amino acids and peptides during digestion in the human gut. The present review examines the effects of different processing techniques, such as curing, drying, ripening, comminution, aging, and marination on the digestibility of muscle proteins. The review also examines how the source of muscle proteins alters the gastrointestinal protein digestion. Processing techniques affect the structural and functional properties of muscle proteins and can affect their digestibility negatively or positively depending on the processing conditions. Some of these techniques, such as aging and mincing, can induce favorable changes in muscle proteins, such as partial unfolding or exposure of cleavage sites, and increase susceptibility to hydrolysis by digestive enzymes whereas others, such as drying and marination, can induce unfavorable changes, such as severe cross-linking, protein aggregation, oxidation induced changes or increased disulfide (S-S) bond content, thereby decreasing proteolysis. The underlying mechanisms have been discussed in detail and the conclusions drawn in the light of existing knowledge provide information with potential industrial importance