The effect of potassium lactate on the free amino acid composition, lipid oxidation, colour, microbiological, and sensory properties of ready-to-eat pastırma, a dry-cured and dried meat product

Abstract

In this study, the effects of potassium lactate (PL, Potassium-L-2-hydroxy-propionate, Potassium-L-Lactate) usage (0%, 0.5%, 1.0%, 2.0% PL of curing mixture) in addition to NaCl and sodium nitrite as curing agent on the physico-chemical, microbiological and sensory properties of ready-to-eat pastırma were investigated. The usage of PL affected pastırma properties as pH (P \ 0.01), TBARS (P \ 0.01), salt (P \ 0.01), residual nitrite content (P \ 0.01), a* value (P \ 0.01), microbial properties (P \ 0.01) (total aerobic mesophylic bacteria, lactic acid bacteria, Micrococcus/Staphylococcus, yeast-mould count) and amino acid levels [lysine (P \ 0.01), isoleucine (P \ 0.01), leucine (P \ 0.01), methionine (P \ 0.05), phenylalanine (P \ 0.01), valine (P \ 0.05), threonine (P \ 0.01), tryptophan (P \ 0.05), aspartic acid (P \ 0.05), glutamic acid (P \ 0.05), asparagine (P \ 0.05), serine (P \ 0.01), histidine (P \ 0.01), glycine (P \ 0.01), alanine (P \ 0.01), proline (P \ 0.01), cystine (P \ 0.05) and norvaline (P \ 0.01)]. According to results of sensory analysis, the difference among pastırma samples including PL was not significant (P [ 0.05).

Effects of potassium lactate on sensory attributes, bacterial community succession and biogenic amines formation in Rugao ham

“…The Aw significantly decreased with the increase of potassium lactate from 0% to 2% in semimembranosus and biceps femoris samples. These results were consistent with previous research by Fulladosa et al [16] and Aksu et al [17], who found that potassium lactate could contribute to the increase of pH and the decrease of Aw, moisture and NaCl content. pH, Aw, moisture and NaCl content are the basic physical properties that may affect quality of meat products.…”

“…It has been confirmed that TVBN could be produced by Enterobacteriaceae [41], Bekhit et al [39] found that TVBN also had a positive correlation with total aerobic bacterial count, which was similar with our result that TVBN and total aerobic bacterial count both significantly decreased with the increase of potassium lactate from 0% to 2%. Gelabert et al [8] and Aksu et al [17] also found that potassium lactate reduced total viable count and the growth of Enterobacteriaceae in fermented sausages and pastırma. These results suggested that the decrease of TVBN values was related to the inhibition of microbial growth and the prevention of excessive proteolysis.…”

“…Aksu et al [17] has confirmed that potassium lactate could prevent the lipid excessive oxidation and protein excessive degradation, resulting in the increase of a* value, and the development of gummy/tight structure. These characteristics further affected palatability of meat products [9,16].…”

“…Total aerobic bacterial count was carried out by methods of Aksu et al [17], in sterile ultra clean bench, 10 g of mixed samples was homogenized in 90 mL sterile 0.9% saline solution in a sterile homogeneous bag for 90 s. Appropriate dilutions (10 -1 -10 -4 ) were made with sterile 0.9% saline solution and 1 mL dilutions were plated onto the Plate Count Agar (PCA, Oxoid, Unipath, Basingstoke, UK) by coating method, then inverted incubated for 72 h at 37 ℃. The colonies were counted by Colony Meter (Xun Minor Technology Co., Ltd, Hangzhou, China) and expressed as CFU per gram of sample.…”

“…Most of researchers studied the effect of potassium lactate on microorganisms in dry-cured meat products by cultured enumeration [4,17], while the variation of microbial community structure in dry-cured meat products has not been investigated in detail when potassium lactate was added as curing agent. Recently, High-throughput sequencing (HTS) technology can deeply and reliably characterize microbial community, which relies on the amplification of specific regions in the bacterial 16S rDNA gene [18].…”