Aluminum ROPP caps, known in Chinese as "Roll-On Pilfer Proof" caps, are screw caps formed directly on the container by applying pressure. These caps are made entirely of aluminum, and the threads are created on the bottle mouth using specialized capping machines.
The key feature of ROPP caps is their one-time forming process. Unlike traditional pre-formed screw caps, ROPP caps are rolled directly onto the bottle after filling. This ensures perfect fit and sealing, while also providing tamper-proof functionality.
HAOMEI Aluminum, a professional bottle cap manufacturer, offers diameters including 28mm, 30mm, 31.5mm, 35mm, and 38mm, with 31.5mm aluminum cap being the most commonly used size. Aluminum ROPP caps are widely used for glass bottles of olive oil, wine, beverages, and pharmaceutical liquids.
Why Choose Aluminum ROPP Caps for Olive Oil?
Olive oil is highly sensitive to light, heat, and oxygen, requiring full protection to preserve quality. Aluminum ROPP caps excel in this regard, making them an ideal choice for olive oil producers.
Olive oil is a food product extremely sensitive to light, heat, and oxygen, requiring comprehensive protection to maintain its quality. Aluminum ROPP bottle caps excel in this regard, making them an ideal choice for olive oil producers.
Oxygen barrier is one of the most important functions of aluminum ROPP bottle caps. Unsaturated fatty acids in olive oil are easily oxidized and rancid upon contact with oxygen, leading to reduced nutritional value and unpleasant flavors.
Through its precise structural design, the aluminum ROPP bottle cap effectively isolates air, slowing down the oxidation process and ensuring that the olive oil maintains its optimal flavor and nutritional components within its shelf life.
Light exposure accelerates the oxidation process of olive oil, leading to photo-oxidative deterioration. The opaque nature of the aluminum ROPP bottle cap effectively blocks the effects of ultraviolet rays and other light on the olive oil.
The olive oil bottle cap forms a tight connection with the glass bottle neck, preventing not only liquid leakage but also blocking the entry of external contaminants, ensuring product hygiene and safety. Appropriate torque control ensures a good seal without being too tight, making it difficult for consumers to open.
Specifications of Aluminum ROPP Bottle Caps
| Product Name | Aluminum ROPP Cap |
| Diameter | 28mm, 30mm, 31.5mm, 35mm, 38mm |
| Height | Customizable |
| Material | Aluminum (3105 / 8011) |
| Thickness | 0.17-0.25 mm |
| Color Options | Green, Black, Gold, Customizable |
| Liner | Food-grade EPE |
| Printing Options | Side printing, screen printing |
| Type | Screw cap |
| Applications | Olive oil, wine, beverages, pharmaceuticals |
| Sample | Available |
| MOQ | 80,000 pieces |
Common Sizes and Applications
| Size | Suitable Bottle | Application |
| 31.5×24mm | Glass olive oil bottle | 250ml / 500ml olive oil |
| 31.5×44mm | Tall glass bottle | 500ml / 1L olive oil |
| 35×24mm | Wine / edible oil bottle | Gift-pack olive oil |
| 30×35mm | PET oil bottle | Mid-range dining oil |
FAQ
Q1: Do aluminum ROPP caps affect the taste of olive oil?
A1: No. The inner liner is made of food-grade EPE or PVDC materials, which are odorless, non-migratory, and chemically inert. They fully comply with food contact standards (FDA, EU REACH), so the cap does not affect flavor, color, or aroma.
Q2: Can aluminum ROPP caps be reused?
A2: ROPP caps feature a tamper-proof ring that breaks upon first opening, preventing resealing. They are single-use but fully recyclable, supporting environmental sustainability.
Q3: What color options are available for aluminum ROPP caps?
A3: Common colors include gold, green, black, silver, red, and dark blue. Custom colors can be made according to the RAL color chart. Green and gold are popular choices for premium and natural product branding.
Q4: What is the minimum order quantity (MOQ) for ROPP caps?
A4: For custom printed caps, the typical MOQ is 10,000-50,000 pieces. Some manufacturers, like HAOMEI, can provide small trial orders for product testing.
Q5: Can ROPP caps be printed with logos or patterns?
A5: Yes. Techniques such as screen printing, pad printing, hot stamping, and UV printing allow for brand logos, QR codes, and anti-counterfeit designs, enhancing recognition and brand appeal.
