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- Sajib, Mursalin, 1987, et al.
(författare)
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Effect of antioxidants on lipid oxidation in herring (Clupea harengus) co-product silage during its production, heat-treatment and storage
- 2022
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322 .- 2045-2322. ; 12:1
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Tidskriftsartikel (refereegranskat)abstract
- Provided high product quality, ensilaging can be used to valorize fish filleting co-products into a silage suitable for food applications. However, a documented challenge for products from hemoglobin-rich fish raw materials is the high susceptibility to lipid oxidation, calling for stabilization by antioxidants. In a comparison among different rosemary-containing antioxidants and isoascorbic acid, we here found that the commercial mixture Duralox MANC-213 (MANC) provided the best protection against peroxide value and 2-thiobarbituric acid reactive substances (TBARS) development during ensilaging of herring filleting co-products (0–7 days, 22 °C), and also during subsequent heat-treatment (30 min, 85 °C). Increasing MANC concentration from 0.25 and 0.75 to 1.25% lowered TBARS values from 43.53 and 25.12 to 18.04 µmole TBARS/Kg silage, respectively, after 7 days of ensilaging. During storage at 4 °C/22 °C in presence of MANC, 1.25% provided the highest protection with 87–90% and 66–73% lower TBARS, at 4 °C and 22 °C, respectively, at 6 months compared to the controls. At this time point, heat-treated silages had lower protein degree of hydrolysis and free amino acids values than the non-heat-treated one. Regardless of antioxidant addition, total volatile basic nitrogen (TVB-N) formation still increased during the storage, but, overall, TVB-N values in silages were below the acceptable limit of 30 mg TVB-N/100 g fish for human consumption. Together with lipid oxidation data, this suggests that herring silage produced in presence of antioxidants can be used both for high-quality feed and food applications.
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| 2. |
- Sajib, Mursalin, 1987, et al.
(författare)
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Pilot-Scale Ensilaging of Herring Filleting Co-Products and Subsequent Separation of Fish Oil and Protein Hydrolysates
- 2022
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Ingår i: Food and Bioprocess Technology. - : Springer Science and Business Media LLC. - 1935-5130 .- 1935-5149. ; 15:10, s. 2267-2281
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Tidskriftsartikel (refereegranskat)abstract
- In this study, ensilaging of herring ( Clupea harengus ) flleting co-products was taken from lab-scale to pilot scale (1500 L) while monitoring the protein degree of hydrolysis (DH) and lipid oxidation. Subsequently, the possibility of recovering fish oil and protein hydrolysates using batch centrifugation at diferent g-forces/times was investigated. Around 38% DH was recorded after 2-day pilot-scale ensilaging of herring co-products at ambient temperature (i.e., ~22 °C), which was similar to the DH found in lab-scale (40% after 2 days; 22 °C). The lipid oxidation marker 2-thiobarbituric acid reactive substances (TBARS) reached 20 µmole TBARS/kg silage after 2-day ensilaging. Centrifugation of the silage at 3000–8500 ×g for 2–20 min revealed successful separation into fsh oil and protein hydrolysates. Heat-treating the silage (85 °C; 30 min) prior to centrifugation resulted in signifcantly higher oil and hydrolysates recoveries; the same being true for increased g-force. At 8500×g, the recovery of oil and hydrolysates were 9.7 and 53.0% w/w, respectively, from heat-treated silage, while recoveries were 4.1 and 48.1% w/w, respectively, from non-heat treated silage. At 4500×g, being a more scalable approach, corresponding numbers were 8.2 and 47.1% (w/w) as well as 2.0 and 40.2% (w/w). The recovered fsh oil contained 8% EPA and 11% DHA of total fatty acids. Free fatty acids (FFA), peroxide value (PV), p-anisidine value (p-AV), and total oxidation (TOTOX) values of oils were in the range of 4–7% (FFA), 3.6–3.7 meq/kg oil (PV), 2.5–4.0 (p-AV), and 9.9–11.1 (TOTOX), respectively, which were within the acceptable limits for human consumption specifed by the GOED voluntary monograph. The recovered protein hydrolysates contained peptides in the molecular weight range 0.3–6 kDa (~ 37%) and 11–34 kDa (~ 63%). Also, the remaining solids contained 15–17% (w/w) protein, having 44–45% essential amino acids. Overall, the results suggest that herring co-product silage is a valuable source of fsh oil and protein hydrolysates, paving the way for ensilaging based-biorefning of herring co-products into multiple products.
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