Ammonia (NH₃) and total volatile nitrogen (TVN) in preserved and unpreserved stored, whole fish

Abstract

Total volatile nitrogen (TVN), ammonia ( N H , ) and amide-N were analysed in fish stored without and with preservatives. In well preserved fish the increase in NH,-N during storage was accompanied by a parallel decrease in amide-N. It is concluded that N H , may originate from glutamine and probably also j o m asparagine. In unpreserved material other sources may dominate.

Nutritional value of stored fish silage as a protein source for young rats

“…Conventional protein (N x 6.25) and total volatile nitrogen (TVN) were determined as described by Haaland and Njaa (1988). Ash was determined by ignition at 550°C.…”

Shelf-life extension on fillets of Atlantic Salmon (Salmo salar) using natural additives, superchilling and modified atmosphere packaging

“…This analysis is often used as spoilage indicator for fresh seafood held on ice (Haaland and Njaa, 1988). Ten grams of sample were added to the Kjeldahl flask consisting of magnesium oxide (2 g) (Merck KGaA, Darmstadt) and distilled water (300 mL) was added before connecting it to the Kjeldahl system.…”

Effect of Garlic Oil and Modified Atmosphere Packaging on the Quality of Chilled Shrimp

“…TVB‐N values is commonly used as criteria for assessing the fishery product quality and its increment is related to the activity of spoilage bacteria and endogenous enzyme . Figure c indicates that TVB‐N values progressively increased during storage for all treatments.…”