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The imidazoquinoline type (IQ-type) is recognized as the most mutagenic activity in heterocyclic amines currently, and closely associated with a variety of cancers and neurodegenerative diseases of human. The precursors of IQ-type HAs are free amino acids, reducing sugars, and creatine/creatinine, and these precursors can undergo a series of chemical reactions at high temperature, and intermediate products such as free radicals and reactive carbonyl compounds are formed, which are the basis for the formation of IQ-type HAs. The exogenous substances added to the meat products during the thermal processing affected the IQ-type HAs formation to varying degrees. There are three main action mechanisms of the exogenous substances inhibiting IQ-type HAs, including competitive inhibition mechanism of precursors, free radical scavenging mechanisms, and active carbonyl compounds capturing mechanism. This article focuses on the formation process of IQ-type HAs and the inhibitory mechanism of exogenous substances, and clarified the reaction pathway of IQ-type HAs generation, and elaborated the action mechanism of exogenous substances inhibiting the formation of IQ-type HAs in detail. This paper provides theoretical guidance for effectively controlling the IQ-type HAs formation during the thermal processing of meat products.

In order to investigate the effect of curing time on the edible quality and oxidative characteristics of compound low-sodium yak meat products, in this experiment, complex low-sodium yak meat was selected to investigate the effects of curing time (12, 18, 24, 30 and 36 h) on the edible quality and oxidative characteristics. The results showed that prolonging the curing time significantly reduced the cooking loss (P

In order to investigate the quality changes during the storage period and predict the shelf life of Xinjiang pepper chicken legs, this study focused on pH value, color, thiobarbituric acid reactive substances (TBARS), total volatile basic nitrogen (TVB-N), total viable count, coliform bacteria, and sensory attributes as evaluation criteria. Accelerated degradation tests were conducted to examine the quality changes of the chicken legs at different storage temperatures (35 ℃ and 45 ℃). The shelf life endpoint was based on a sensory score of 70 points or a total bacterial count close to national standards and to predict the shelf life at room temperature (25 ℃). The results showed that with the continuous extension of storage time, the pH value of pepper chicken legs at different storage temperatures first decreased and then increased, and the overall L* value showed a downward trend. The a* value, b* value, TBARS value, TVB-N content, and total bacterial count all showed an upward trend, while the sensory score continued to decline. During the storage period, the change rate at 45 ℃ was higher than 35 ℃. At 35 ℃ storage temperature, the theoretical shelf life was 24 days, and at 45 ℃ storage temperature, the theoretical shelf life was 9 days, and there was an unacceptable loss of sample quality at the end of the shelf life. According to the Q10 model, Q10=2.6 was calculated, and the theoretical shelf life was predicted to be 62 days under room temperature (25 ℃) conditions.

【Objective】The study aims to explore the effects of low-light stress on the main quality characteristics of fruits of different muskmelon varieties.【Method】The content changes of carbohydrates, carotenoids and chlorophyll in different fruit positions (pedicle, areola and pulp) of three varieties (Xizhoumi No. 1, Zaohuanghou and Jiashi) of muskmelon under different light intensities (100%, 42% and 23% transmittance) at different development stages (0, 3, 7, 14, 21, 35, 40, 60 d after blooming) were investigated.【Result】Results showed that contents of fruit starch, sucrose and reducing sugar all increased continuously during fruit development and the highest contents exhibited at mature stage (35 d), and Xizhoumi No. 1 had the highest starch content (10.835%), while Jiashi had the lowest starch content (8.342%). The pulp and areola of the fruits of three varieties showed higher sucrose content than that in pedicle, but no difference in reducing sugar content. The contents of carotenoid and chlorophyll increased during fruit development but decreasedat full ripe stage (60 d after blooming). Low-light stress significantly reduced the carbohydrate content, increased carotenoid and chlorophyll contents, and most significant effect was found under transmittance 23% treatment, under which the contents of starch, sucrose and reducing sugar in Xizhoumi No. 1 muskmelon reduced by 32.3%, 29.87% and 28.02%, while contents of carotene and chlorophyll increased by 19.47% and 13.98%, respectively. The contents of starch, sucrose and reducing sugar in Zaohuanghou muskmelon reduced by 32.63%, 25.09% and 20.24%, and the contents of carotene and chlorophyll increased by 54.74% and 21.06%, respectively. The contents of starch, sucrose and reducing sugar in Jiashi muskmelon reduced by 41.08%, 32.39% and 39.1%, and the contents of carotene chlorophyll increased by 55.20% and 31.79%, respectively. Compared with Xizhoumi No. 1 and Zaohuanghou muskmelons, the Jiashi muskmelon showed the lowest starch and chlorophyll contents and the highest sucrose and reducing sugar contents, and exhibited the most significant decline of starch, sucrose and reducing sugar contents, and increase of carotenoid and chlorophyll contents, indicating that the Jiashi muskmelon was affected most significantly by low-light stress and showed poorest low-light tolerance.【Conclusion】The low-light stress reduces the commercial quality of muskmelon fruits, and the quality is worse when the light transmittance is lower. Jiashi muskmelon is most sensitive to low-light stress.

Unfermented jujube pulp (UFJP), fermented jujube pulp (FJP) in high and low doses were fed to constipated ICR mice. Defecation function, serum gastrointestinal regulatory peptide, fecal short-chain fatty acids (SCFAs) and gut microbial composition were assessed. Results showed that high-dose FJP could protect intestinal mucosa tissue, shorten the first black feces defecating time by 17 % and increase the number and wet weights of black feces by 72 % and 71 %, respectively, within 6 h. High-dose FJP significantly down-regulated the somatostatin level and up-regulated gastrin level in constipated mice, compared with low-dose FJP and UFJP. High-dose FJP intervention regulated the microbiota profile, which afterwards restored microbiota, like Bacteroidetes, Bifidobacterium and Lactobacillus, to a less unhealthy state. This study provides convincing in vivo evidence that high-dose FJP supplementation through daily diet could be a promising approach to effectively alleviate constipation and modulate gut health.

To analyze systematically the effects of marinated in eggs on edible quality of different meats during cooking of several traditional Chinese dishes, marinated in whole egg or egg white, and different egg white addition were chosen to analyze the effects on the edible quality of pork patties, beef patties, and lamb patties. The results showed that, at the addition of 10% and marinated for 30 min, when marinated in egg white, the water content of the pork patties and lamb patties were significantly increased (P

Alternaria gaisen is one of the main fungi that cause fruit postharvest diseases due to its wide contamination and toxin production. The application of lactic acid bacteria shows great industrial application as a natural food preserver due to the advantages of being safe and non-toxic. In order to obtain a natural preservative against this fungus, this study aimed to evaluate the effectiveness of cell- free supernatants (CFS) produced by Lactobacillus pentosus 86 as antimicrobials in vitro against A. gaisen. Results indicated that CFS displayed excellent thermostability and enzymatic stabilities with an antifungal activity over 85%. Under thermal (40–100 °C) treatments, different protease solution and acidic conditions (pH 2–4), the antifungal activity of CFS maintained up 80%. However, when the pH reached 6, its antifungal ability completely disappeared. CFS inhibited mycelial growth of A. gaisen by destroying the hyphae membrane, leading to the leakage of nucleic acids and proteins, and hyphae collapsed and shriveled. CFS also changed the spore’s morphology, resulting in cell membrane damage, intracellular leakage, and organelles aggregation. The increase of cell membrane permeability of spores caused a 30% mortality rate. Therefore, the CFS of L. pentosus 86 has the potential for controlling fruit diseases caused by A. gaisen.

The present study was conducted to analyze the level of four priority polycyclic aromatic hydrocarbons (PAHs), including benzo[a]pyrene (BaP), chrysene (Chr), benzo[a]anthracene (BaA), and benzo[b]fluoranthene (BbF), in traditionally smoked chicken products marketed in China. The results show that the amount of ƩPAH4 (the sum of four different PAHs: BaP, Chr, BaA, and BbF) was 30.43–225.17 and 18.75–129.54 µg/kg in the skin and meat of smoked chicken products, respectively. The content of ƩPAH4 in the smoked skin was significantly higher as compared to the smoked meat (p < 0.05). The calculation of MOE (margin of exposure) results suggested the possibilities of ingestion risk associated with the consumption of smoked chicken skin. Furthermore, the formaldehyde content in the skin of smoked chicken was 2.17–6.84 mg/kg and 0.86–2.95 mg/kg in the smoked meat. These results indicate that optimization or alternative methods for food processing should be developed to reduce the high level of harmful substances formed during processing to ensure the safety of smoked chicken products. Moreover, along with harmful substances, the moisture content and color of traditionally smoked chicken were analyzed to provide a practical reference for healthy, safe and green processing technology for smoked chicken.

To investigate the characteristic aromatic compounds, present in the traditional fermented koumiss of the Kazakh ethnic group in different regions of Xinjiang, GC-IMS, and GC-MS were used to analyze the volatile compounds in koumiss from four regions. A total of 87 volatile substances were detected, and esters, acids, and alcohols were found to be the main aroma compounds in koumiss. While the types of aroma compounds in koumiss were similar across different regions, the differences in their concentrations were significant and displayed clear regional characteristics. The fingerprint spectrum of GC-IMS, combined with PLS-DA analysis, indicates that eight distinctive volatile compounds, including ethyl butyrate, can be utilized to distinguish between different origins. Additionally, we analyzed the OVA value and sensory quantification of koumiss in different regions. We found that aroma components such as ethyl caprylate and ethyl caprate, which exhibit buttery and milky characteristics, were prominent in the YL and TC regions. In contrast, aroma components such as phenylethanol, which feature a floral fragrance, were more prominent in the ALTe region. The aroma profiles of koumiss from the four regions were defined. These studies provide theoretical guidance for the industrial production of Kazakh koumiss products.

In this study, the influence of Na content of dry-cured beef by partial replacement with KCl, L-lysine, and L-histidine was investigated during processing. Dry-cured beef aged over 57 days, compared to control groups (100% NaCl), salt substituted groups (SS, 39.7% of NaCl, 51.3% of KCl and a blend of 7% L-lysine and 2% L-histidine); had a significant impact on the proteolysis index and total free amino acids, lower activities, and gene levels of cathepsin B and L, as well as reduced contents of protein carbonyls and thiol group. The present study provides a successful strategy for improvement of the perceived saltiness and inhibition of the bitterness, while exhibiting no significant negative effects on color or textural properties.

The high sodium diet is harmful to the human body. In this study, beef was cured with some salt substitutes, namely SS, 39.7% NaCl, 51.3% KCl, 7% L-lysine and 2% L-histidine, in order to reduce the Na content for the final products, and salt substitute effects the physicochemical, lipolytic, and flavor characteristics of dry-cured beef by determining free fatty acids, lipase activity, volatile compounds, and water mobility. The results showed that the lipase activity and unsaturated fatty acids were significantly increased due to the present of L-lysine and L-histidine. In addition, the SS could also enhance the lipoxygenase activity and promoted the lipid oxidation and influenced volatile compounds. The changes of T21 and T22 showed that the water mobility in SS was higher (P < .05) than in the control group. Moreover, the cadaverine, histamine, and tyramine were detected in 57-day dry-cured beef, being below their toxic limits. The present study demonstrated that salt substitute by L-lysine and L-histidine alter the water distribution and mobility, improved the amounts and types of volatile compounds, while had no influence in the quality of product.

Tamarix ramosissima has been widely used as barbecue skewers for the good taste and unique flavor it gives to the meat, but the effects of T. ramosissima on heterocyclic amine (HA) formation in roast lamb are unknown. The influence of T. ramosissima extract (TRE) on HA formation, precursors’ consumption, and free radicals’ generation in roast lamb patties were elucidated by UPLC-MS, HPLC, and electron spin resonance (ESR) analysis, respectively. Six HAs were identified and compared with the control group; the total and polar HAs decreased by 30.51% and 56.92% with TRE addition at 0.30 g/kg. The highest inhibitory effect was found against 2-amino-1-methyl-6-phenylimidazo[4,5-f]pyridine (PhIP) formation (70.83%) at 0.45 g/kg. The addition of TRE retarded the consumption of HA precursors, resulting in fewer HAs formed. The typical signal intensity of free radicals in roast lamb patties significantly decreased with TRE addition versus the control group (p < 0.05), and the higher the levels of the TRE, the greater the decrease in signal intensity. We propose that the inhibitory effects of TRE on HA formation, especially on polar HAs, were probably achieved by retarding the consumption of precursors and preventing free radicals from being generated in roast lamb patties. These findings provide valuable information concerning TRE’s effectiveness in preventing HA formation through both the precursor consumption and free radical scavenging mechanisms.

Free radicals are ubiquitous in roasted foods. In this work, lipid-derived carbon-centered alkyl radical formation was first studied in roasted meat by electron spin resonance (ESR). The influence of antioxidants on the inhibition of free radicals was investigated. The results showed that the high temperature, high heat transfer rate, and high polyunsaturated fatty acid (PUFA) content resulted in high radical content in roasted meat, while the high water content in meat retarded radical formation. The 0.03% addition of tea polyphenols (TPP) significantly reduced radical formation during roasting (p < 0.05), whereas the 0.03% rosemary extract (RE) had no significant inhibitory effect (p > 0.05). These results suggested that water retention and the addition of TPP would decrease radical generation during the roasting of meat.

Tamarix has been widely used as barbecue skewers to obtain a good taste and a unique flavor of roast lamb in China. Many flavonoids have been identified from Tamarix, which is an important strategy employed to reduce the formation of heterocyclic amines (HAs) in roast meat. Isorhamnetin, hispidulin, and cirsimaritin from Tamarix ramosissima bark extract (TRE) effectively inhibit the formation of 2-amino-1-methyl-6-phenylimidazo[4,5-b] pyridine (PhIP), the most abundant HAs in foods, both in roast lamb patties and in chemical models. According to the results of the GC-MS analysis, TRE and the three flavonoids significantly reduced the contents of phenylacetaldehyde, an important intermediate involved in PhIP formation at three levels. A subsequent ultra performance liquid chromatography-mass spectrometry (UPLC-MS) analysis revealed that these flavonoids trapped phenylacetaldehyde by forming interaction adducts. The formation of three postulated adducts, 8-C-(E-phenylethenyl)isorhamnetin, 6-C-(E-phenylethenyl)isorhamnetin and 8-C-(E-phenylethenyl)hispidulin, in the chemical models and roast lamb patties was further confirmed by a TOF-MS/MS analysis. Our results demonstrate that TRE and the corresponding flavonoids trap phenylacetaldehyde to form adducts and thus inhibit PhIP formation, suggesting their great potential beneficial effects on human health.

As a natural potential resource, Tamarix ramosissima has been widely used as barbecue skewers for a good taste and unique flavor. The polyphenolics in the branch bark play a key role in the quality improvement. The purposes of the present work were to explore the polyphenolic composition of T. ramosissima bark extract and assess their potential antioxidant and antimicrobial activities. Hispidulin and cirsimaritin from T. ramosissima bark extract were first identified in the Tamarix genus reported with UPLC-MS analysis. Isorhamnetin (36.91 μg/mg extract), hispidulin (28.79 μg/mg extract) and cirsimaritin (13.35 μg/mg extract) are rich in the bark extract. The extract exhibited promising antioxidant activity with IC50 values of 117.05 μg/mL for 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 151.57 μg/mL for hydroxyl radical scavenging activities, as well as excellent reducing power with an EC50 of 93.77 μg/mL. The bark extract showed appreciable antibacterial properties against foodborne pathogens. Listeria monocytogenes was the most sensitive microorganism with the lowest minimum inhibitory concentration (MIC) value of 5 mg/mL and minimum bactericidal concentration (MBC) value of 10 mg/mL followed by S. castellani and S. aureus among the tested bacteria. The T. ramosissima bark extract showed significantly stronger inhibitory activity against Gram-positive than Gram-negative bacteria. Nevertheless, this extract failed to show any activity against tested fungi. Overall, these results suggested that T. ramosissima shows potential in improving food quality due to its highly efficacious antioxidant and antibacterial properties.