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    20kg Bulk Box - Black Onyx Sirloin Whole SB-5

    $1,450.00

    20kg Black Onyx sirloin SB-5, 230 day grain finished. Reliable eating quality, good flavour and consistent performance for value-driven wholesale buyers.

    Pickup available at Peter Augustus Store Camp Hill

    Usually ready in 24 hours


    Buy 20kg Bulk Box - Black Onyx Sirloin Whole SB-5

    Value-focused Black Onyx sirloin delivering reliable eating quality, solid tenderness,

    and consistent performance for busy wholesale kitchens.

    Diamantina's 20kg Bulk Box of Black Onyx Sirloin Whole SB-5 offers a remarkable dining experience with its SB-5 marbling, ensuring tender texture and rich flavour. The Black Onyx breed, known for its superior quality, combined with the 230-day grain-finished feeding program, enhances the flavour profile, providing a consistent and satisfying taste. Sourced from Australia, our sirloin guarantees excellent cooking performance, whether you choose slicing or roasting. 

    Chefs and culinary enthusiasts often select our Black Onyx Sirloin for its reliable tenderness and flavour consistency. Ideal for those who appreciate high-quality beef, our product serves perfectly in professional kitchens and home settings. With its exceptional grading and source quality, our sirloin ensures a memorable meal experience every time. Choose to buy the 20kg Bulk Box of Black Onyx Sirloin Whole SB-5 for a rewarding purchase that guarantees satisfaction and value.

    Why Choose 20kg Bulk Box - Black Onyx Sirloin Whole SB-5?

    For a cost-effective solution with consistent performance, choose our 20kg Bulk Box - Black Onyx Sirloin Whole SB-5.

    • Marble Score: SB-5 for reliable tenderness.
    • Feeding: Grain finished for 230 days.
    • Origin: Sourced from Australia.
    • Weight: 20kg for large-scale needs.
    • Breed: Premium Black Onyx beef.

    Product Overview

    • 20kg bulk box of Black Onyx sirloin whole (SB-5)
    • Grain finished for a minimum of 230 days
    • Cost-effective option with dependable eating quality
    • Consistent marbling with good beef flavour
    • Australian family-owned

    Performance & Quality

    • SB-5 specification for value-focused grading
    • Reliable tenderness and flavour consistency
    • Consistent performance across steak and roasting applications
    • Balanced quality for everyday premium service

    Wholesale Advantages

    • 20kg bulk format for efficient commercial use
    • Ideal for slicing, roasting, and portion control cuts
    • Strong yield with minimal waste
    • Cost-effective solution for high-volume operations

    Who Should Choose This 20kg Bulk Box - Black Onyx Sirloin Whole SB-5?

    Our 20kg Bulk Box - Black Onyx Sirloin Whole SB-5 caters to various buyers seeking premium meat solutions. This product suits professional chefs looking for reliable tenderness and flavour consistency in large volumes. 

    Home cooks preparing for family gatherings or those who appreciate batch cooking will find this bulk option economical. Caterers needing cost-effective meat solutions for events can rely on its consistent performance. Restaurants aiming to deliver a high-grade dining experience benefit from its quality and grading. Businesses specialising in meat distribution can also their offerings with this premium bulk sirloin.

    Best Cooking Methods for Sirloin

    Cooking the 20kg Bulk Box - Black Onyx Sirloin Whole SB-5 requires precise techniques to achieve its value-focused grading and ensure reliable tenderness. The Black Onyx Sirloin benefits from fat rendering, which enriches flavour consistency and contributes to consistent performance across different cooking methods. Our sirloin's grain-finished nature for 230 days demands careful heat management to maintain its cost-effective solution.

    Pan Sear: Use medium-high heat to create a rich crust, searing each side for about 3-4 minutes. Allow resting for 5 minutes to let the juices redistribute.

    Grill: Preheat the grill to medium. Cook for 6-7 minutes on each side, ensuring a beautiful char while keeping the interior tender.

    BBQ: Utilise indirect heat, maintaining a temperature of 350°F. Cook for approximately 20 minutes, turning halfway for even cooking.

    Oven: Preheat to 400°F and roast for 15-20 minutes until desired doneness is achieved. Rest for 5 minutes to juiciness before slicing.

    Delivery & Storage

    Delivered fresh, chilled in vacuum-sealed packaging for maximum freshness.

    • Store refrigerated at 0–4°C
    • Consume by the use-by date or freeze on arrival
    • Keep vacuum sealed until ready to use
    • Thaw under refrigeration before cooking if frozen
    • Do not thaw at room temperature
    • Do not refreeze once thawed

    Striploin

    Striploin, also known as Sirloin, New York Strip, or Porterhouse (when bone-in), is a premium cut prized for its bold flavour and balanced tenderness. It comes from the short loin of the cow and features a fine grain with a satisfying bite. It's a favourite among chefs and home cooks alike for its generous marbling and robust, beefy taste.

    Frequently Asked Questions

    Our Beef

    Where does our beef come from?

    All of our beef is from our parent company Stanbroke Beef. This is important as the quality of the beef and ultimately your eating experience is determined by the care that has been shown to the animal during each stage of the production process. Any undue stress the animal experiences at any stage of its life is detrimental to the beef it will produce.

    As Stanbroke owns and operates each stage of the production process, strict best practices are followed to ensure the animals always receive the highest of care and that’s why at Peter Augustus we can guarantee the quality of our product each and every time.

    SB Marble Scores

    What is an SB Marble Score?

    The SB Score measures intramuscular fat (the white flecks in the meat). Higher scores mean more marbling, which results in superior tenderness, juiciness, and a richer, buttery flavour.

    Which score should I choose?

    • SB 0–2: Leaner, traditional beef flavour with a robust texture.
    • SB 3–5: Our "everyday premium" level; a perfect balance of flavour and tenderness.
    • SB 6–10: The indulgent peak, featuring extreme marbling for a melt-in-your-mouth experience.

    Meat Quality & Colour

    What is vacuum sealing and how does it extend shelf life?

    Vacuum sealing removes air from the packaging, slowing oxidation and bacterial growth to extend freshness and shelf life. When stored correctly at 0–4°C, you can expect the following guide:

    • Beef primals & whole cuts: up to 28 days
    • Beef (steaks): up to 21 days
    • Beef (bone-in): up to 14 days
    • Lamb: up to 28 days
    • Pork: up to 10 days
    • Ham: up to 30 days
    • Sausages: up to 9 days
    • Chicken (frozen): up to 12 months
    • Salmon (frozen): up to 12 months
    • Smoked salmon: up to 30 days

    For longer storage, keep products frozen at -18°C, where vacuum sealed meat can last 1 to 3 years depending on the cut and consistency of temperature.

    Once opened, the shelf life reverts to that of standard fresh products, so we recommend consuming promptly.

    For longer delivery routes, some items may arrive partially or fully frozen to ensure they remain within safe temperatures during transit.

    Why is my steak dark in the vacuum pack?

    Our beef is vacuum sealed to lock in freshness and extend shelf life by removing oxygen. This can cause the meat to appear darker or slightly purplish due to natural myoglobin, which is completely normal.

    Once opened, simply let your steak rest out of the packaging for 10 to 20 minutes. As it’s exposed to air, it will “bloom” back to its natural rich red colour. Rest assured, your beef is fresh and perfectly safe to enjoy.

    Is it safe to eat?

    Yes. If the “Use By” date is within range your meat is fresh. Any colour variation from vacuum sealing is normal and will return to its natural red once opened and allowed to bloom.

    Delivery & Packaging

    What are your delivery fees?

    We offer a range of pickup and delivery options to suit you:

    • Free pickup is available from our Camp Hill store in Brisbane. Simply select pickup at checkout.
    • Free shipping is available on subscription-only orders.
    • Free shipping is automatically applied to orders over $200.
    • Refrigerated delivery starts from $30 (including GST), with final pricing based on your location, order size, and weight. Enter your address at checkout to calculate the exact rate.

    All delivery orders are packed in a food-safe, insulated chilled box with ice packs to maintain safe temperatures throughout transit.

    Can I request custom cutting instructions?

    Yes, our butchers are happy to accommodate custom cutting requests where possible and safe to do so. For example, you may like a rump cap portioned into steaks. Simply specify your preferred thickness or weight per piece, such as approximately 2.5cm or 300g portions.

    You can add these instructions in the “View Cart” section before checkout using the notes box or send them through to us via email.

    How is my order kept cold?

    We use specialist refrigerated courier partners to keep your order within the cold chain from dispatch to delivery. Each order is packed in a thermal carton lined with VISYCELL® sustainable insulation, a food-grade, biodegradable material designed to maintain a consistent chilled temperature throughout transit.

    We also include large 1kg ice gel packs in every box to help keep your products at optimal temperature. Our packaging has been tested to maintain safe temperatures for a few hours after delivery when left in a shaded area.

    My box arrived looking a bit scuffed. Is the meat okay?

    While the outer carton may show signs of handling during delivery, the internal insulation is specifically built to protect the contents and preserve freshness.

    What should I do if I have concerns?

    If you detect any issues with the temperature or seal of your products upon arrival, please contact our team immediately so we can find a solution for you.