Adding value to under-utilised Irish fish roe: a physico-chemical and sensory comparison of cured Irish pollock ( Pollachius pollachius ) roe with commercial mullet ( Mugil cephalus ) and cod ( Gadus morhua ) products

Irish marine fish roe is generally discarded at sea or processed as low value-added fishmeal and not utilised as nutritious seafood ingredients. Locally sourced pollock roes were salted, air-dried (Mediterranean-style) and compared to similar commercial mullet and cod products for: weight; moisture content; pH; instrumental texture and colour; and sensory attributes. Raw pollock roes averaged 105 g (n = 25). Roes lost on average 3.1% moisture (w/w) after a 2-h salting period and 48.8% weight reduction was observed after an average 105 h air-drying time. The moisture content of pollock was not significantly different to commercial products. Average pH for pollock, mullet and cod products was 5.9, 5.4 and 5.7, respectively (P < 0.05). Pollock and mullet had similar hardness, but cod was significantly harder than both, when measured instrumentally. Total colour difference (∆E*) between the surface of pollock and cod, and that of pollock and mullet was 7.5 and 3.0, respectively. Sensory assessment of sliced and powdered products, using 9-point hedonic and 5-point just-about-right (JAR) scales, was conducted with 38 consumers. Pollock received the highest scores for overall liking and intention to purchase compared to commercial mullet and cod products, averaging 5.6, 5.6 and 4.9, respectively, for sliced roe products, and 6.3, 5.3 and 6.1 for powdered products. Penalty analysis of JAR showed “overall liking” was impacted by the flavour being “too fishy”. In conclusion, pollock had similar characteristics and acceptable sensory attributes compared to commercial products presenting opportunities to expand the range of value-added roe products (e.g., trout, salmon) available, while also contributing to waste reduction.

Comparison of Chemical Composition and Safety Issues in Fish Roe Products: Application of Chemometrics to Chemical Data

Processed fish roes are acquiring considerable importance in the modern food market, entering more and more often as an ingredient in food preparation and as caviar substitutes. In this study, we defined quality, traceability and safety issues related to processed fish roe products from different species. The results obtained allowed to distinguish eggs originated from different fish species and to discriminate between fish roes and caviar samples obtained from four different sturgeons species. We observed that roes showed a trend of grouping according to ecological and reproductive habits of fish species. We highlighted the differences between eggs originated by farmed and freshwater fish, enriched in n6 polyunsaturated fatty acids (PUFAs), and all the others, in which n3 PUFAs were prevalent. In addition, we evaluated processed fish roes under a food safety point of view, combining microbiological analysis with the determination of organic acids, used in some products as authorized preservatives. Microbiological characterization has proved a general good hygienic level for these products. Organic acids determination showed values in compliance with European Union (EU) regulations in almost of samples; in some cases, we found a mismatch between the organic acids detected and what was reported in labels. Processed fish roes could be considered a safe product that can provide to human nutrition a valuable content of essential fatty acids.

Identification and molecular docking study of fish roe-derived peptides as potent BACE 1, AChE, and BChE inhibitors

Acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and beta-secretase 1 (BACE 1) play vital roles in the development and progression of Alzheimer's disease (AD).