A protein powder production line using rice (broken rice) as raw material, with core products including concentrated protein powder (RPC,~60-75%), isolated protein powder (RPI, ≥ 90%), and hydrolyzed protein powder (RHRP, molecular weight<3 kDa). The three products share a "wet extraction+multi-stage purification" platform, and only switch paths between the "refining depth" and "enzymatic hydrolysis/drying" stages. The process diagram is as follows:
1. Raw material pretreatment
-Cleaning and stone removal → magnetic separation → color selection, impurities<0.1%
-Soaking tank (hot water at 50-55 ℃ for 2 hours)+bubbling and flipping to prevent spoilage; Winter matching plate heat exchanger circulation heating
2. Wet grinding and liquefaction (starch stripping)
-Colloidal mill (120-150 mesh) → concentration 18-22 ° B é
-Double stage high-temperature spraying: Stage I 105-108 ℃/10min, Stage II 120-130 ℃/45min; High temperature resistant α - amylase 5 ‰, DE value 12-15
-Three phase spiral centrifugation: heavy phase (fiber+residual starch) → feed; Light phase (sugar solution) → by-product concentrated glucose syrup; Medium phase rich protein slurry enters the protein line
3. Concentrated protein powder (RPC) route - "one membrane, one drying"
-Disc centrifugation to remove fine fibers → UF ultrafiltration (5 kDa) cycle washing filtration twice, solid content increased from 8% to 18%
-Tube bundle drying (0.4MPa, 15min)+air flow flash evaporation (instantaneous 90 ℃), moisture content ≤ 10%
-Grind to 80 mesh, protein ≈ 65%, ash content ≤ 4%, powder yield ≥ 92%
4. Route of protein isolate powder (RPI) - "double membrane+surfactant"
-Dilute the protein slurry to 10%, add a composite surfactant (HLB 8-20, 2 ‰) and react at 45 ℃ for 1 hour to dissolve residual lipids and pigments
-12 stage cyclone washing → after heavy phase adjustment, sterilized by 0.1 μ m microfiltration → concentrated to 25% solids by NF nanofiltration
-Spray sterilization (120 ℃/4s) → Plate and frame pressure filtration → Filter cake moisture content of 45%
-Double stage drying with airflow and fluidized bed (inlet temperature 160 ℃, outlet temperature 75 ℃), moisture content ≤ 7%; Ultra fine pulverization D90=15 μ m, finished protein ≥ 90%, fat ≤ 2%, solubility (NSI) ≥ 75%
5. RHRP route - "enzymatic hydrolysis+spray"
-Using high-pressure pretreatment (500MPa, 25 ℃, 30min) to open the protein structure
-Add complex protease (alkaline: neutral: trypsin=2:3:1, 0.1%) at pH 9.5, hydrolyze at 50-55 ℃ for 10-12 hours, with a hydrolysis degree of 18-22%
-Enzymatic inactivation at 90 ℃ → vacuum concentration to 20% of solids → spray drying (centrifugal, 180/75 ℃), moisture ≤ 4%, protein ≥ 93%, peptide<3kDa accounting for 85%, low bitterness value, instant dissolution in cold water
6. Post processing and packaging shared section
-Multi stage screening+metal detection (Fe ≥ 0.3mm) → nitrogen protection packaging, O ₂ ≤ 1%
-Automatic ton bag, 25kg paper bag, and 5kg aluminum foil small bag in parallel, meeting different scenarios of feed, food, and sports nutrition
7. Intelligent and Green Technology
-PLC-SCADA for the entire process, with online closed-loop control for key pH, temperature, and flow rates; AI model predicts cleaning nodes, reducing CIP water consumption by 25%
-The evaporation condensate water is reused for soaking, with a comprehensive energy consumption of 620kWh · t ⁻¹ powder, which is 18% lower than traditional processes
-By product syrup and rice residue are used to produce glucose powder and dietary fiber, achieving a "zero waste" cycle
Through the three-stage coupling of "liquefaction membrane separation enzymatic hydrolysis", the same production line can switch between RPC/RPI/RHRP products within 30 minutes, providing a high gross profit, multi scenario, and sustainable protein powder flexible manufacturing solution for rice deep processing.