The performance of a mixed starter culture, SAS-1, comprised of the autochthonous strains Lactobacillus sakei ACU-2 and Staphylococcus vitulinus ACU-10, was evaluated into the production process of a ...traditional dry sausage. Microbiological, physicochemical and sensory analyses were carried out to accomplish this goal. Results showed an improvement in performance through the introduction of SAS-1; adding mixed starter culture rapidly decreased pH, inhibited the growth of contaminant microorganisms and enhanced the beneficial ones, diminished TBARS, and highlighted color and aroma attributes. However, most influential organoleptic descriptors among consumer acceptance were not affected by the addition of the starter. This starter culture would represent a valuable tool to improve the homogeneity of artisanal manufacture of this traditional food.
The effects of Limosilactobacillus fermentum 332 on quality characteristics in fermented sausage were explored in terms of physicochemical characteristics, volatile flavor components, and Quorum ...sensing (QS). The results showed that the pH of fermented sausage decreased from 5.20 to 4.54 within 24 h with the inoculation of L. fermentum 332. Lightness and redness were significantly improved, and hardness and chewiness were significantly increased after the addition of L. fermentum 332. With the inoculation of L. fermentum 332, the thiobarbituric acid reactive substance content decreased from 0.26 to 0.19 mg/100 g and total volatile basic nitrogen content decreased from 2.16 to 1.61 mg/100 g. In total, 95 and 104 types of volatile flavor components were detected in the control and fermented sausage inoculated with starter culture, respectively. The AI-2 activity of fermented sausage inoculated with L. fermentum 332 was significantly higher than that of the control and positively correlated with viable count and quality characteristics. These results provide support for further research on the effect of microorganisms on the quality of fermented food.
Adulteration of high-quality meat products using lower-priced meats, such as pork, is a crucial issue that could harm consumers. The consumption of pork is strictly forbidden in certain religions, ...such as Islam and Judaism. Therefore, the objective of this research was to develop untargeted metabolomics using liquid chromatography-high resolution mass spectrometry (LC-HRMS) combined with chemometrics for analysis of pork in beef meatballs for halal authentication. We investigated the use of non-targeted LC-HRMS as a method to detect such food adulteration. As a proof of concept using six technical replicates of pooled samples from beef and pork meat, we could show that metabolomics using LC-HRMS could be used for high-throughput screening of metabolites in meatballs made from beef and pork. Chemometrics of principal component analysis (PCA) was successfully used to differentiate beef meatballs and pork meatball samples. Partial least square-discriminant analysis (PLS-DA) clearly discriminated between halal and non-halal beef meatball samples with 100% accuracy. Orthogonal projection to latent structures-discriminant analysis (OPLS-DA) perfectly discriminated and classified meatballs made from beef, pork, and a mixture of beef-pork with a good level of fitness (R
X = 0.88, R
Y = 0.71) and good predictivity (Q
= 0.55). Partial least square (PLS) and orthogonal PLS (OPLS) were successfully applied to predict the concentration of pork present in beef meatballs with high accuracy (R
= 0.99) and high precision. Thirty-five potential metabolite markers were identified through VIP (variable important for projections) analysis. Metabolites of 1-(1
-hexadecenyl)-sn-glycero-3-phosphocholine, acetyl-l-carnitine, dl-carnitine, anserine, hypoxanthine, linoleic acid, and prolylleucine had important roles for predicting pork in beef meatballs through S-line plot analysis. It can be concluded that a combination of untargeted metabolomics using LC-HRMS and chemometrics is promising to be developed as a standard analytical method for halal authentication of highly processed meat products.
The aim of this study was to determine ochratoxin A (OTA) concentrations in the raw materials and cooked meat products made from pigs sub-chronically exposed to OTA. The treated animal group (n=5) ...was administered with 300μg OTA/kg of feed for 30days, whereas the control group (n=5) was left untreated. OTA concentrations were quantified using immunoassay (ELISA) and high performance liquid chromatography with fluorescence detection (HPLC-FD). OTA concentration was the highest in the kidney, followed by the lungs, liver, blood, spleen, heart, and adipose tissue. As for the final meat products, the highest average OTA concentration was detected in black pudding sausages (14.02±2.75μg/kg), then in liver sausages (13.77±3.92μg/kg), while the lowest was found in pâté (9.33±2.66μg/kg). The results pointed out that a sub-chronic pig exposure leads to the accumulation of OTA in raw materials and consequently in meat products, whose level of contamination is directly dependent on OTA contents in raw materials used for their production.
•OTA in raw materials and meat products made from treated pigs were determined.•ELISA and HPLC-FD methods were used.•OTA was the highest in the kidney and the lowest in adipose tissue.•The highest OTA was detected in black pudding sausages and the lowest in pâté.•Meat products contamination is directly dependent on OTA contents in raw materials.
The objective of the present study was to analyze the prevalence of Salmonella in multiple food commodities in the People's Republic of China by performing a meta-analysis. Accordingly, we screened ...studies that examined the prevalence of Salmonella in PubMed, Embase, and Web of Science databases. Methodological quality assessment and heterogeneity analyses were performed for included studies. The prevalence rate with the 95% confidence interval (CI) was selected as the effect size. Subgroup analyses for each food type were conducted and then stratified by regions, food chain processing points, and seasons. In total, 49 studies were included in the meta-analysis, among them, 8 (16.3%) studies were deemed "high risk," 13 (26.5%) studies were "unclear risk," and 28 (57.2%) studies were "low risk." The overall prevalence rate of Salmonella was 20.0% (95% CI: 15.9 to 24.4). The prevalence rate of Salmonella in raw meat products was 23.6% (95% CI: 19.8 to 27.6), which was higher than that in aquatic products, 13.7% (95% CI: 3.1 to 29.9), milk products, 0.9% (95% CI: 0.0 to 3.9), frozen convenience foods, 6.5% (95% CI: 4.4 to 8.9), ready-to-eat foods, 2.0% (95% CI: 1.1 to 3.2), vegetables and fruits, 0.9% (95% CI: 0.0 to 5.2), and shell eggs, 4.2% (95% CI: 3.0 to 5.7). Subgroup analyses revealed that prevalence rates of Salmonella in raw meat products from abattoirs, 26.3% (95% CI: 17.4 to 36.3) and retail stores, 30.0% (95% CI: 24.6 to 35.8) were higher than those determined from farms, 10.2% (95% CI: 7.0 to 13.9); P < 0.05); however, no significant difference was observed in the prevalence of Salmonella stratified by different geographical regions or seasons (P > 0.05). On the basis of these findings, high levels of Salmonella contamination could be detected in raw meat products in China, and the prevalence rate of Salmonella in raw meat products from abattoirs and retail stores was high.
The aim of the work was to determine the impact of two variants (A and B) of smoking (differing in temperature values, furnace, top and bottom of the smoking chamber and the length of smoking time) ...in the sausage technological process carried out in a traditional smoking chamber with an indirect furnace. The research material consisted of medium-ground sausages: Country, Home and Bieszczady sausages. The research showed that, as the temperature in the smoking chamber and the smoking time changed, the following texture parameters decreased: cycle hardness 1 and 2, springiness, gumminess and chewiness. In addition, there were shown statistically significant differences (
< 0.05) in the chemical composition of Country sausage between the applied smoking variants. It was also found that the temperature of the furnace, upper and lower smoking chamber and the length of smoking time did not have a statistically significant influence on the share of red (a*) and yellow (b*) in the analysed sausages.
The aim of this study was to investigate antimicrobial resistance and the presence and transferability of corresponding resistance genes and integrons in bacteria isolated from cooked meat samples in ...the People's Republic of China. A total of 150 isolates (22 species belonging to 15 genera) were isolated from 49 samples. Resistance of these isolates to antimicrobials was commonly observed; 42.7, 36.0, and 25.3% of the isolates were resistant to tetracycline, streptomycin, and ampicillin, respectively. Multidrug resistance was observed in 41 (27.3%) of the isolates. Sixteen resistance genes, i.e., bla
and bla
(β-lactams), aac(3)-IIa (gentamicin), strA and strB (streptomycin), qnrB and qnrS (fluoroquinolone), sul1, sul2, and sul3 (sulfamethoxazole), cat1 and cat2 (chloramphenicol), and tetM, tetA, tetS, and tetB (tetracycline), were found in 54 isolates. One isolate of Pseudomonas putida carried qnrB, and sequence analysis of the PCR product revealed 96% identity to qnrB2. The qnr genes were found coresiding and were cotransferred with bla genes in two isolates. Twelve isolates were positive for the class 1 integrase gene, and four isolates carried the class 2 integrase gene. However, no class 3 integrase gene was detected. One isolate of Proteus mirabilis carried dfrA32-ereA-aadA2, and this unusual array could be transferred to Escherichia coli. Nonclassic class 1 integrons lacking qacEΔ1 and sul1 genes were found in 2 of the 12 intI1-positive isolates. Our results revealed the presence of multidrug-resistant bacteria in cooked meats and the presence and transferability of resistance genes in some isolates, suggesting that cooked meat products may act as reservoirs of drug-resistant bacteria and may facilitate the spread of resistance genes.
Maillard reaction products are largely responsible for the development of color, taste and especially aroma of thermally treated food. For this reason, our review focused on gathering literature from ...the last 10 years about the influence of the Maillard reaction products formation on food acceptance in aspects of color, texture and flavor. Maillard reaction products have a characteristic odor note and can significantly positively or negatively influence the sensory acceptance of a product. For example, pyrazines and thiols were found in most cases as the most potential odor compounds formed in MR. Another important aspect of high sensorial acceptability is food color. Color development of thermally treated products is mainly attributed to the formation of brown polymers called melanoidins. It was also noted that the increasing concentration of "probably carcinogenic and mutagenic" acrylamide is related to the darker color of a product. Not much attention is focused on the connection between Maillard reaction products formation and textural properties. Therefore, textural properties have been mostly investigated in meat products. Changes in the texture of meat products were estimated as the difference in linkage formations between proteins and polysaccharides.
A method to detect volatile nitrosamines in meat samples was developed using headspace sampling by solid-phase microextraction (HS-SPME), with analysis by GC-MS. A 50/30 µm ...divinylbenzene/carboxen/polydimethylsiloxane fused silica fibre was selected to extract a total of nine volatile nitrosamines: N-nitrosodimethylamine, N-nitrosomethylethylamine, N-nitrosodiethylamine, N-nitrosodi-n-propylamine, N-nitrosomorpholine, N-nitrosopyrrolidine, N-nitrosopiperidine, N-nitrosodi-n-butylamine, and N-nitrosodiphenylamine. Extraction at 65°C for 45 min with 36% (w/v) NaCl were the optimal conditions determined for the extraction of nine nitrosamines. Excellent linearity was obtained for all analytes with determination coefficients greater than 0.997. Recovery rates were between 92 and 113%. The relative standard deviation ranged from 0.81 to 8.0% for six of the nine compounds, and from 16 to 32% for the other three. For seven out of nine nitrosamines, limits of detection were below 3.6 µg kg
−1
and the limits of quantification were below 12 µg kg
−1
. The nitrosamine levels in four varieties of processed meat products were investigated to assess the applicability of the method. Based on the results, the developed HS-SPME-GC-MS method proved to be a simple and efficient technique to detect seven out of nine nitrosamines in meat products with adequate sensitivity, accuracy and precision.
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