Steam explosion processing intensifies the nutritional values of most crop byproducts: Morphological structure, carbohydrate-protein fractions, and rumen fermentation profile

Abstract

To investigate the feasibility of steam explosion on the exploitation of ruminant feedstuff, the morphological structure, carbohydrate-protein fractions, and rumen fermentation profile of five typical crop byproducts (corn cob, rice straw, peanut shell, millet stalk, and sugarcane tip) were analyzed before and after steam explosion processing. The results showed that these crop byproducts had different physicochemical properties and rumen fermentation profiles, most of which could be improved by steam explosion processing, i.e., more rough morphological surface, much-broken structure, more digestible carbohydrate fraction (non-NDF +49.92–452.24%), faster gas production rate (c +9.72–68.75%), higher dry matter digestibility (DMD48 +11.38–47.36%), more available energy (ME −3.69–+42.13%, except for peanut shell), along with more unavailable protein fraction (ADICP +27.16–102.70%). It is suggested that steam explosion processing could intensify the feeding value of most crop byproducts for ruminants, but with a caution of heat damage to proteins.

Substituting effects of winged bean tuber-modified starches for cassava chip in concentrate diets on rumen fermentation, nutrient utilization, and blood metabolites in Thai native beef cattle

“…The present study shows that the complete substitution of CSC with WBTS results in 10-20% increased concentrations of ruminal C3 proportion, whereas decreased proportions of C2 are due to the fact that in the rumen, the metabolic pathways for C3 creation are more effective at transforming energy than those for C2 and C4 production [3,10]. He et al [22] suggested that ruminants may benefit from a more effective source of energy supply if they were fed steam feedstuffs. It's probable that the steam-flaking process broke down the protein's disulfide bond and the starch's embedded structure, making the starch surface more palatable for ruminal microbial breakdown enzymes [20,21], hence enhancing the starch's ruminal degradability when fed at a replacement optimal level of 10 to 25% of concentrate, which improved the degradability of starch and ruminal fermentation in the rumen [7,21].…”

“…According to Makizadeh et al [34], slow-fermented starch treated with steam produced high short-chain fatty acids (SCFA). Similarly, He et al [22] suggested that raw material and steam processing in millet stalks and sugarcane tips could decrease the C2:C3 molar ratio and increase the molar proportion of C3. However, flaking and steaming changed the amylopectin in grains or cereals by turning it…”

“…The greater NDF digestibility observed in the substituting group (10 to 30% of WBTS) when compared to the control group could be attributed to the steam processing starch method used for WBTS. He et al [22] reported that the steaming process used in feed preparation could lead to a patchy, broken, irregular, and melted morphology of structural carbohydrates. This occurs due to the hydrolysis or melting of some cellulose and hemicellulose components on the surface when materials are exposed to high temperatures [23].…”

“…This occurs due to the hydrolysis or melting of some cellulose and hemicellulose components on the surface when materials are exposed to high temperatures [23]. Consequently, this process has the potential to alter and increase the specific surface area of the feedstuff, thereby enhancing feed utilization and digestibility [21,22,24]. Yahaghi et al [25] demonstrated that replacing barley with steam-treated sorghum grain in lamb diets could lead to improved ruminal fermentation and fiber digestibility.…”

Effect of steam explosion treatment on structural and physicochemical properties, and potential application of soluble dietary fiber from grain and oil processing by‐products: A review

“…The structure of SDF from Tartary buckwheat bran with SE treatment (1.2 Mpa, 90 s) was changed noticeably. The physical and chemical properties and hypoglycemic function in vivo of SDF were also significantly improved (He, Huang, et al, 2022). Animal experiments have shown that SE can reduce blood glucose levels in diabetic mice, regulate the intestinal microbiota and insulin resistance in diabetic mice, and protect the liver and pancreas of mice.…”