Shiqi Hao

Air-dried mutton is a traditional, culturally significant meat product, yet its spontaneous fermentation is inherently constrained by unstable microbial communities, leading to batch-to-batch quality inconsistency and potential food safety hazards. Elucidating whether composite starter cultures can modulate the microbiota and enhance product quality is therefore critical for standardized industrial processing. Herein, we investigated the effects of a defined starter culture (composed of Lactiplantibacillus plantarum and Pediococcus pentosaceus in a 2:1 ratio, with a total inoculum of 10⁸ CFU/g) on the quality and flavor of air-dried mutton, comparing inoculated samples (FJ) with naturally fermented controls (ZR). The fermentation was conducted at 30 °C and 95% relative humidity (RH) for 24 h, followed by air-drying at 4 °C for 21 d, with all assays performed in three biological and three technical replicates. Starter inoculation significantly reduced the pH, water activity (Aw), total volatile basic nitrogen (TVB-N), and thiobarbituric acid reactive substances (TBARS) values while improving sensory acceptability (p < 0.05). Amplicon sequencing analysis revealed a lactic acid bacteria (LAB)-dominated microbiota in FJ samples, with elevated abundances of Pediococcus and Lactobacillus and reduced abundance of Pseudomonas. The inoculated group also exhibited altered eicosapentaenoic acid content and a more diverse volatile flavor profile, with eight key aroma compounds positively correlating with LAB abundance. These findings demonstrate that composite starter inoculation improves physicochemical quality, stabilizes the microbial community, and enhances flavor in air-dried mutton. Further mechanistic validation and scale-up trials are required to confirm industrial applicability.

Traditional air-dried meat from Ordos, Inner Mongolia, is a distinctive fermented meat product with unique ethnic and regional features. However, systematic studies on its quality and flavor variations across production regions remain limited. This study characterized 15 traditional Ordos air-dried meat samples (3 biological replicates per region) from five representative areas (Dalad Banner, Otog Banner, Otog Front Banner, Wushen Banner, Ejin Horo Banner) via physicochemical analysis, high-throughput 16S rRNA gene sequencing, and GC-MS. Results showed pH 5.63–5.73 and water activity (Aw) 0.61–0.66. Wushen Banner samples had significantly lower TVB-N and TBARS contents. Proteobacteria and Firmicutes dominated, with marked regional divergence at the genus level. Ninety-one volatile compounds were identified, 11 as key odor-active components. This study clarifies regional quality discrepancies and interrelationships among microbiota, flavor, and physicochemical traits, providing a theoretical basis for process optimization and industrial development.

Air‐dried beef is a traditional specialty dried meat product that has a rich history in Inner Mongolia. In‐depth understanding of the characteristic flavor substances of air‐dried meat in different regions can help branding of traditional air‐dried meat products and sustainable development of the air‐dried meat industry in Inner Mongolia. This study aims to investigate the characteristic flavors of air‐dried beef from various regions of Inner Mongolia (Ordos, Xinlingol, and Chifeng) by using electronic nose and GC‐MS combined with ROAV value and explore the impact of the vacuum tumbling curing process on the flavor of air‐dried meat. The samples from each region were found to contain characteristic flavor substances such as alcohols, aldehydes, hydrocarbons, and oxygenates. There are five characteristic flavor substances unique to the Ordos region: 3‐dodecanol (5.938), 4‐methyl‐5‐decanol (32.686), 2,4‐dimethyl‐2‐pentanol (4.139), methylheptenone (67.445), and 3‐ethyl‐2,5‐dimethylpyrazine (4.256); three characteristic flavor substances unique to the Xilingol region: isovaleraldehyde (68.917), ethyl phenylacetate (3.746), and thymol (2.091); and two characteristic flavor substances unique to the Chifeng region: 2‐heptanol (3.984) and 6‐methyl‐2‐heptanone (6.191). Vacuum tumbling curing not only improved the pH (6.35) and L^∗ value (33.74) of air‐dried meat but also increased the variety of flavor substances characteristic of air‐dried meat, including trans‐2‐decenol (2.989), isopentanol (0.585), trans‐2‐nonenal (2.937), methyl decyl ketone (4.836), phenylacetic acid (4.262), and benzoic acid (0.554). In conclusion, the addition of vacuum tumbling curing process in the industrial production of air‐dried beef products can increase the curing efficiency and improve the flavor of air‐dried beef products.

Food ingredient adulteration, especially the adulteration of milk and dairy products, is one of the important issues of food safety. The large price difference between camel milk powder, ovine, and bovine milk powder may be an incentive for the incorporation of ovine and bovine derived foods in camel milk products. This study evaluated the use of ordinary PCR and real-time PCR for the detection of camel milk powder adulteration based on the presence of ovine and bovine milk components. DNA was extracted from camel, ovine, and bovine milk powder using a deep-processed product column DNA extraction kit. The quality of the extracted DNA was detected by amplifying the target sequence from the mitochondrial Cytb gene, and the extracted DNA was used for the identification of milk powder based on PCR analysis. In addition, PCR-based methods (both ordinary PCR and real-time PCR) were used to detect laboratory adulteration models of milk powder using primers targeting mitochondrial genes. The results show that the ordinary PCR method had better sensitivity and could qualitatively detect ovine and bovine milk components in the range of 1% to 100% in camel milk powder. The commercial camel milk powder was used to verify the practicability of this method. The real-time PCR normalization system has a good exponential correlation (R² = 0.9822 and 0.9923) between ovine or bovine content and Ct ratio (specific/internal reference gene) and allows for the quantitative determination of ovine or bovine milk contents in adulterated camel milk powder samples. Accuracy was effectively validated using simulated adulterated samples, with recoveries ranging from 80% to 110% with a coefficient of variation of less than 7%, exhibiting sufficient parameters of trueness. The ordinary PCR qualitative detection and real-time PCR quantitative detection method established in this study proved to be a specific, sensitive, and effective technology, which is expected to be used for market detection.