The quality of pork is a growing concern for consumers and producers in China. Lean-type pigs, while efficient in growth, often lack intramuscular fat. This deficiency reduces tenderness, juiciness, and flavor, which are key attributes for consumer acceptance. Researchers at Yangtze University investigated whether corn-soybean meal-based fermented feed could improve growth performance and pork quality in lean-type finishing pigs.
Eighty Duroc-Landrace-Yorkshire pigs were divided into two groups. One group received a basal diet, while the other received a diet supplemented with 10% fermented feed. The trial lasted 70 days, with growth, meat quality, fatty acid composition, and gut microbiota analyzed.
Growth gains and feed efficiency
The pigs fed fermented feed showed significant improvements in final body weight and average daily gain. Their feed-to-gain ratio was also reduced, indicating better feed efficiency. Importantly, average daily feed intake did not differ between groups, suggesting the improvements were due to feed quality rather than quantity.
Key outcomes included:
- ✅ Higher final body weight in the fermented feed group.
- ✅ Increased average daily gain compared to control pigs.
- ✅ Lower feed-to-gain ratio, reflecting efficient nutrient utilization.
Better meat quality and flavor traits
Fermented feed improved several meat quality traits. Intramuscular fat content increased, leading to higher marbling scores and better meat color. Drip loss and shear force were reduced, indicating juicier and more tender pork.
Chemical analysis showed that moisture, protein, and ash contents remained stable, but intramuscular fat rose significantly. This change directly enhanced sensory attributes such as tenderness and flavor.
Healthier fatty acid profiles
The fatty acid composition of pork was notably altered. Fermented feed increased levels of monounsaturated and polyunsaturated fatty acids while reducing saturated fatty acids. These changes improved nutritional indices linked to human health.
Key fatty acid shifts included:
- ✅ Elevated oleic acid (C18:1 n-9).
- ✅ Increased linoleic acid (C18:2 n-6) and arachidonic acid (C20:4 n-6).
- ✅ Reduced stearic acid (C18:0).
These modifications enhanced the health-promoting index and hypocholesterolemic-to-hypercholesterolemic ratio, making the pork nutritionally superior.
Gut microbes and gene regulation
Microbial analysis revealed that fermented feed reduced harmful Campilobacterota abundance while increasing beneficial genera such as Clostridium_sensu_stricto and Oscillospiraceae. Gene expression analysis showed higher levels of lipid metabolism-related genes, including sterol regulatory element-binding protein 1c (SREBP1c), peroxisome proliferator-activated receptor gamma (PPARγ), stearoyl-CoA desaturase 5 (SCD5), and fatty acid translocase/CD36 (FAT/CD36). These changes supported intramuscular fat deposition and improved meat quality.
Towards tastier, healthier pork
The study demonstrated that corn-soybean meal-based fermented feed significantly improved growth performance, meat quality, fatty acid profiles, and gut microbiota in lean-type finishing pigs. By enhancing intramuscular fat and beneficial fatty acids, fermented feed produced pork that was both tastier and healthier.