Lipid deterioration of mackerel caught in Icelandic waters was studied, as affected by different frozen storage temperatures (À18°C vs. À25°C) and seasonal variation (August vs. September). The lipid stability was investigated by analyses of hydroperoxide value (PV), thiobarbituric acid reactive substances (TBARS), free fatty acids, as well as changes in fatty acid composition. Results showed significant lipid deterioration with extended storage time, where the lower storage temperature showed significantly more protective effects. Furthermore, a higher lipid oxidation level was recorded for fish caught in September than in August, although lipid hydrolysis occurred to be greater for fish in August than in September. Moreover, results indicated a rather stable level of omega-3 fatty acid during the whole frozen storage period. The analysis indicated that both lipid oxidation and hydrolysis were affected by the frozen storage temperature and the stability differed with regard to season of catch.

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The aim of these experiments was to evaluate the effect of brining, modified atmosphere packaging (MAP), and superchilling on the quality changes of cod loins as measured by microbial, sensory, and chemical analysis. Unbrined and brined (2.5 +/- 1.0% NaCl) cod loins were kept in styrofoam boxes (air) and under modified atmosphere (MA, CO(2)/O(2)/N(2): 50/5/45) at 0, -2, and -3.6 degrees C. Samples were examined over a 4-wk period. Total viable psychrotrophic counts and counts of H(2)S-producing bacteria reached higher numbers in the air-packed brined fish at -2 and -3.6 degrees C than in comparable unbrined groups, being significantly different (P < 0.05) at the lower temperature. However, lower counts of these bacteria were obtained in the brined MAP fish than in comparable unbrined fish. Counts of Photobacterium phosphoreum increased most rapidly in air- and MA-packed loins kept at 0 degrees C. Lower counts were found at superchilled temperatures. According to sensory analysis the shelf life of unbrined air-packed loins was about 11 d at 0 degrees C and 14 to 15 d at -2 degrees C. The shelf life of MA-packed unbrined loins was about 14 to 15 d at 0 degrees C but 21 d at -2 degrees C. Thus, synergism of combined superchilling (-2 degrees C) and MA led to a considerable shelf life increase for unbrined loins despite the fact that processing and packaging took place 4 to 5 d post-catch. The shelf life of air-packed brined loins at -2 degrees C was 12 to 15 d but only 13 d under MA. The same synergistic effect did therefore not apply to brined loins as with unbrined ones.

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The critical role of indigenous crops in the socioeconomic growth of developing nations has necessitated calls for accelerated exploitation of staples. Cocoyam, Xanthosoma sagittifolium, is food for over 400 million people worldwide and is the most consumed aroid in West Africa. However, it remains an underexploited food resource. This study reviews existing literature and also makes use of primary data from interviews with indigenous cocoyam farmers, processors, consumers, and cocoyam scientists in the research Institutes of Ghana, to provide insight into existing nomenclature of the species, indigenous knowledge on food uses, nutritional value, and potential novel food applications of cocoyam. Adaptable technologies in conformity to new trends in food science that could be employed for in‐depth molecular studies and further exploitation of the crop are also discussed. It is envisaged that the provided information would contribute to global efforts aimed at exploiting the full potential of indigenous crops for sustainable food and nutrition security.

Unstable conditions are commonly encountered during industrial storage and transportation of frozen fish. Temperature stress and fluctuations may increase the amount of unfrozen water in the muscle and enzymatic activity and lipid oxidation can thus still take place during frozen storage. The aim of this study was to investigate the changes of characteristics of different muscle types of herring at unstable modelled conditions during storage and transportation. Compositional changes, lipid oxidation and lipid hydrolysis were monitored in light and dark muscle of Atlantic herring (Clupea harengus), during frozen storage, as affected by temperature stress (samples were stored at − 25 °C for 2 months, then stressed at − 12 °C for 1 month, followed by storage at a stable − 25 °C for the remaining storage duration), and compared to samples stored at a stable − 25 °C for 14 months. The dark muscle was more sensitive to lipid oxidation than the light muscle, leading to faster degradation. Increased lipid oxidation and lipid hydrolysis were observed in temperature‐stressed samples of both muscle types. The study demonstrated the importance of avoiding temperature stress during industrial frozen storage and transportation to improve the quality and shelf life of frozen herring products. Removal of dark muscle by deep skinning could benefit both processors and customers regarding the shelf life and nutritional value of the light herring muscle.