Changes in Biogenic Amines and Microbiological Analysis in Albacore (Thunnus alalunga) Muscle during Frozen Storage

Abstract

Albacore specimens of extra quality were analyzed for their biogenic amine contents after 1, 3, 6, and 9 months of frozen storage at -18 degrees C or -25 degrees C. A high-performance liquid chromatography method involving a linear elution gradient was optimized for the identification and determination of putrescine, cadaverine, histamine, spermidine, and spermine in albacore tuna. Putrescine was the biogenic amine that showed the highest increase, reaching concentrations of 59.04 ppm (815% of the initial level) and 68.26 ppm (942% of the initial level) in the white muscle of albacore after 9 months of frozen storage at -18 and -25 degrees C, respectively. Cadaverine, histamine, and spermidine concentrations were below 3, 5, and 11 ppm, respectively, after 9 months of frozen storage, while spermidine underwent a significant decrease at both storage temperatures. Microbiological analysis confirmed the absence of species of Enterobacteriaceae in 75% of the albacore specimens after 9 months of frozen storage; coliforms were always below 3 CFU/g. The survival rate of the psychrotrophic microorganisms after 9 months of frozen storage at -25 degrees C was 4.6%, while 38.9 and 92.1% of the aerobic mesophiles present in the white muscle of albacore before freezing survived 9 months of storage at -18 and -25 degrees C, respectively.

Cloning and Sequencing of the Histidine Decarboxylase Genes of Gram-Negative, Histamine-Producing Bacteria and Their Application in Detection and Identification of These Organisms in Fish

“…Although microorganisms are most likely alive in such processing plants, we may overestimate the risk when frozen fish meat is used for processing. Different workers (3,11,15) have showed that freezing inactivates gram-negative histamine producers. On the other hand, the ability of PCR to detect dead microorganisms may be beneficial in frozen, salted, or smoked fish sample when we attempt to identify the species responsible for histamine accumulated before such processing treatments that killed the histamine-producing bacteria.…”

Sensory, microbial and chemical effects of a slurry ice system on horse mackerel (Trachurus trachurus)

“…Samples were then mixed with 225 ml of peptone water (1 g l −1 ) and homogenised in a stomacher (Seward Medical, London, UK) as previously described. 14,15 In all cases, serial dilutions from the microbial extracts were prepared in peptone water. Total aerobes were investigated in plate count agar (PCA, Oxoid Ltd, London, UK) as described elsewhere.…”

Hydrogen peroxide pretreatment induces osmotic stress tolerance by influencing osmolyte and abscisic acid levels in maize leaves

“…Derivatization of biogenic amines was carried out according to developed method of Ben-Gigirey et al (1998). One milliliter of each extracted sample or standard amine solution was mixed with 200 µl of 2 M sodium hydroxide and 300 µl of sodium hydrogen carbonate.…”

“…Extraction of leaf samples and High Performance Liquid Chromatography (HPLC) determination of biogenic amines (putrescine (Put), spermine (Spm), and spermidine (Spd)) were carried out according to the procedures developed by Ben-Gigirey et al (1998). To extract biogenic amines, 10 ml of 0.4 M perchloric acid containing a known amount of 1,7-diaminoheptane as an internal standard was added to 5 g of leaf samples, and the mixture was homogenized for 3 min.…”