Impact of−2°C Superchilling before Refrigerated Storage (4 and 8°C) on the Microbiological and Sensory Qualities of Cold-Smoked Salmon

Abstract

Detection and enumeration of Listeria monocytogenes and total spoilage bacteria in 40 batches of cold-smoked salmon (one batch = 42 products from the same day of manufacture) straight from the factory were carried out. If L. monocytogenes was detected in at least one of the nine samples analyzed on receipt at the laboratory, 9 products of the same batch were stored for 10 days at 4 degrees C, which was followed by 18 days at 8 degrees C (control), 12 products were superchilled for 14 days at -2 degrees C, and 12 other products were superchilled for 28 days at -2 degrees C and then stored under the same conditions as the control was stored. L. monocytogenes was detected in 7% of the 40 batches analyzed immediately after receipt at the laboratory. L. monocytogenes prevalence was similar (approximately 25%) throughout the storage at 4 and 8 degrees C, both in control and super-chilled products at -2 degrees C for 14 days. After superchilling for 28 days at -2 degrees C, L. monocytogenes was found in 9% of products, and in 39% at the end of the storage above 0 degree C. Moreover, the L. monocytogenes count was higher after 3 and 4 weeks of storage at 4 and 8 degrees C in products superchilled 28 days at -2 degrees C than in control products or in products superchilled for 14 days. Serotype 1/2a-3a and nine genetic groups were identified and found throughout the storage scenario. At the end of shelf life, sensory characteristics of products superchilled for 28 days at -2 degrees C were slightly modified. A decrease in firmness associated with increased tearing of salmon slices was observed as well as a slight amine odor.

Quantification of the extracellular matrix of theListeria monocytogenesbiofilms of different phylogenic lineages with optimization of culture conditions

“…(), with some modifications (Midelet‐Bourdin et al . ), and were classified by lineage (Ward et al . ; Tamburro et al .…”

“…Twenty-seven strains of L. monocytogenes (from environmental, animal, food, clinical and unknown sources) were used in this study (Table 1). All strains were characterized using serogroup PCR as previously described by Doumith et al (2004), with some modifications (Midelet-Bourdin et al 2008), and were classified by lineage (Ward et al 2004;Tamburro et al 2009). Cells were stored in brain-heart infusion (BHI) medium (AES, Combourg, France) supplemented with glycerol (18% v/v) at À20°C.…”

Sensory Characteristics of Various Concentrations of Phenolic Compounds Potentially Associated with Smoked Aroma in Foods

“…Smoked flavor is not a single smoky characteristic, but rather has several different manifestations, such as wood or wood fire [ 1 , 11 , 25 ], rubber [ 1 , 26 , 27 ], and others. Jaffe et al [ 28 ] used a highly trained and skilled descriptive sensory panel to identify, define and reference 14 sensory attributes related to the flavor that is imparted to products during the smoking process.…”

Effect of Curing Method and Freeze-Thawing on Subsequent Growth of Listeria monocytogenes on Cold-Smoked Salmon

“…In the United States, cold-smoked salmon is distributed frozen or under refrigeration (16). In contrast, cold-smoked salmon is distributed as frozen products in Canada if sealed in package without other means of preservation (10), while chilled distribution is the main means of distribution in Europe (7,30). Among the processing procedures, salting, smoking, and freezing are known to influence the survival and growth of L. monocytogenes (49) on cold-smoked salmon.…”