Proximal Composition and Nutritive Value of Raw, Smoked and Pickled Freshwater Fish

Abstract

The aim of the study was to assess protein, fat, salt, collagen, moisture content and energy value of freshwater fish purchased in Polish fish farms. Eight species of freshwater fish (raw, smoked, pickled) were assessed by near infrared spectroscopy (NIRS). The protein content varied between 15.9 and 21.7 g/100 g, 12.8 and 26.2 g/100 g, 11.5 and 21.9 g/100 g in raw, smoked and pickled fish, respectively. Fat content ranged from 0.89 to 22.3 g/100 g, 0.72 to 43.1 g/100 g, 0.01 to 29.7 g/100 g in raw, smoked and pickled fish, respectively. Salt content ranged from 0.73 to 1.48 g/100 g, 0.77 to 3.39 g/100 g, 1.47 to 2.29 g/100 g in raw, smoked and pickled fish, respectively. A serving (150 g) of each fish product provided 53.2–71.9% of the Reference Intake (RI) for protein, 2.21–60.3% of the RI for fat, 21.3–61.3% of the RI for salt and 6.27–24.4% kJ/6.29–24.5% kcal of the RI for energy. Smoked fish had a higher protein and also fat content than raw and pickled fish, while smoked and pickled fish had higher salt content than raw fish. Cluster analysis was performed, which allowed to distinguish, on the basis of protein, fat, salt, collagen and moisture content, mainly European eel.

Growth Performance, Nutrient Digestibility, Blood Profiles, and Gut Integrity of Growing Pigs Fed Pickled Fish Residue with Decreased Salt Content

“…Stirring and speed may rapidly increase the rate of solubility by allowing greater interactions, owing to the lower amount of NaCl on the PFR surface. In this study, the amount of salt in PFR was higher than that found by Mielcarek et al [16], who observed salt content ranging from 1.47 to 2.29%. The difference in the result is associated with differences in the fish species, origin, and pickled fish process.…”

“…In our study, the phosphorus content in PFR was 6.92%, which may cause an imbalance in the ratio of K + and Na + to Cl + in the animal body, ultimately leading to reduced phosphorus absorption [27]. Variations in the pickled fish process, freshwater fish species, storage condition, and duration may have a detrimental effect, inducing a poor quality PFR [16]. The insufficiency of essential amino acids, excess salt content, toxins, and foreign substance leads to poor protein utilization, and therefore decreased growth rate and feed efficiency.…”

“…The improvement of P digestibility may be more relevant in older pigs than younger pigs. Mielcarek et al [16] reported that the crude protein and energy contents in PFR were higher than those in eight freshwater fish species.…”

Investigations of the Polycyclic Aromatic Hydrocarbon and Elemental Profile of Smoked Fish

“…In the present study, there was a significant increase detected in the protein level among fresh and smoked fish, regardless of the kind or species. On the contrary, the total lipid and moisture levels decreased throughout the smoking process in all fish species, which can be explained by fish physically losing fat and moisture during the smoking process [ 34 , 35 ].…”

Estimation of Cadmium in Muscles of Five Freshwater Fish Species from Manzalah Lake, and Possible Human Risk Assessment of Fish Consumption (Egypt)

“…Abdel Kader and Mourad [ 54 ] determined the Cd levels in fish samples obtained from Burullus Lake in Egypt as follows: C. gariepinus (1.66) > O. aureus (1.54) > T. zillii (1.49) > S. galilaeus (1.46) > O. niloticus (1.10 μg/g). Mielcarek et al [ 55 ] estimated that Cd, ranged 0.02–97.0 μg/kg of freshwater fish species from Poland especially smoked fish products. Łuszczek-Trojnar et al [ 56 ] observed that Cd levels in smoked rainbow trout (10.0 ± 1.0 μg/kg) from fish farm, Poland.…”