Nutrient content of fish powder from low value fish and fish byproducts

Abstract

Consuming small‐sized fish species whole, and bones of large fish could contribute significantly to reducing the level of micronutrient and protein malnutrition. These fish products are more affordable and could therefore meet the needs of poor, vulnerable groups, particularly in rural and urban areas where limited economic resources prevent dietary diversity. The objectives of the study were to produce fish powder from dried edible byproducts from fish processing factories, an underutilized fish species, burrito and to determine the physical, micromineral, macronutrient and microbiological quality of the dried fish powder. Edible fish processing byproducts and an underutilized fish, burrito (Brachydeuterus auritus) were cleaned thoroughly and dried with a Council for Scientific and Industrial Research‐Food Research Institute (CSIR‐FRI) gas‐fuelled oven at 55°C for 8 h or until dried. The dried products were milled into powder, and packaged into polythene bags. Proximate analysis of the fish powder was done Official Methods of Analysis (AOAC) methods. Minerals and heavy metals in the fish powder were determined by atomic absorption spectrophotometry (AAS). Microbiological quality was determined by Nordic Committee on Food Analysis Method (NMLK) methods. Tuna trimmings contained 80.71 g/100 g protein, whereas burrito contained 70.40 g/100 g protein. Concentrations of cadmium, arsenic, and mercury varied from <1.00 to 1 mg/kg. Lead was found at 0.04 mg/100 g in tuna frames and gills only. All fish byproducts contained high levels of iron, for example, trimmings contained 16.58 mg/100 g, whereas tuna frames and gills also contained 16.82 and 19.54 mg/100 g, respectively. Burrito contained 8.92 mg/100 g. Zinc levels also ranged from 0.41 mg/100 g in tuna trimmings to 1.88 mg/100 g in tuna gills. The powdered samples according to the standards set by Ghana Standard Authority, were acceptable. Consuming small‐ sized fish species whole, and bones of large fish could contribute significantly to reducing the level of micronutrient and protein malnutrition. These are more affordable and could therefore meet the needs of poor, vulnerable groups.

Biochemical Quality Assessment of Fish Powder

“…One study [30] showed that such variation in concentrations of mineral elements from one species to another was due to the chemical forms of the elements and their concentrations in the local environment. Another study [31] reported that Burrito fish (Brachydeuterus auritus) contains 93.71 mg/100 g phosphorus which is near to the present study. Such low concentration of phosphorus might be due to the removing of head, bones and scales from the fish body.…”

Nutrient composition of fish protein powder developed from Brycinus nurse (Rüppell, 1832)

“…The change in Fe content after processing was found to be significant ( p  < 0.05). Recommended dietary intake (RDI) of iron for children 9–13 years/day is 8 mg (Abbey et al, 2017). Hence, consumption of B. nurse powder could adequately meet the iron needs of children in these age brackets.…”

Properties of bone from Catfish heads and frames

“…The reported lipid content of Catfish frame (Bechtel et al, ), when converted to similar moisture content, was 42 percent, similar to the 41 percent in this study. Lipid content of tuna frame (prepared similarly to the Catfish raw frame in Table ) was reported as 11 percent (Abbey, Glover‐Amengor, Atikpo, Atter, & Toppe, ) or 27 percent (Istiqlaal, ), and for Pollock and Cod, values of 4 and 3 percent were reported (after conversion to 4 percent moisture; Bechtel, )—much lower than the 41 percent in these Catfish samples. In comparison with the treated Catfish frame (1.53 percent lipid), cleaned bones (head and frame) from Cod and Blue whiting had a lipid content of 1.14 and 4.91 percent, respectively, but Salmon and Trout had 38.12 and 34 percent, respectively (Toppe et al, ).…”

“…Protein content of the raw frame (33 percent) was very similar to that reported for Catfish frame (converted to a moisture content of 13.8 percent) with 34 percent (Bechtel et al, ). Raw Tuna frame is reported to have 29 percent protein (Abbey et al, ) or 9 percent (Istiqlaal, ). Protein content of cleaned bone (head and frame) of Cod and Blue whiting was reported as 36 and 42 percent, respectively, and Salmon and Trout had 29 and 31 percent, respectively (Toppe et al, ), compared to the 33 percent found for Catfish in this report.…”

“…Ash content of the raw frame (17 percent) was larger than that reported (Bechtel et al, ) in Catfish frame (11 percent). For Tuna frame, ash content was reported to be 44 percent (Abbey et al, ). The 62 percent ash for the 60‐min enzyme treated was larger than that reported for Cod, Blue whiting, Salmon, or Trout (53, 45, 26, and 27 percent, respectively; Toppe et al, ).…”