What Is RBD Palm Stearin? Specifications, Fractionation, and Uses
- RBD palm stearin is the solid fraction from RBD palm oil fractionation, a white solid at room temperature with melting point 44–56 °C.[1]
- Specifications list FFA maximum 0.2%, moisture and impurities maximum 0.15%, iodine value maximum 48, and color maximum 3 red.[1]
- Its fatty acid composition is dominated by palmitic acid 56–62%, followed by oleic acid 26–32% and stearic acid 4–6%, so its saturation is much higher than regular palm oil.[2]
- It is obtained from dry fractionation of RBDPO yielding about 65% olein and 35% stearin.[3]
- It is used as feedstock for margarine, shortening, vanaspati, soap, wax, confectionery, and bakery fats.[1]
RBD palm stearin is the solid fraction of palm oil rich in palmitic acid. Its high melting point and stability make it an important raw material for margarine, shortening, and trans-free fats.
Contents
What Is RBD Palm Stearin?
RBD palm stearin is the solid fraction obtained from fractionation of refined palm oil. This product is a white solid at room temperature and melts to a clear yellow liquid when heated.[1]
The name stearin refers to the solid fraction rich in saturated triglycerides with high melting points. Unlike olein which is liquid, stearin is solid and provides structure and hardness in fat products.[2]
RBD palm stearin is an important derivative because it can be used as a natural hardstock for trans-free fat formulations, replacing partial hydrogenation needs.[2]
Fatty Acid Composition
RBD palm stearin has a much higher saturated fatty acid content than regular palm oil. Palmitic acid dominates the composition, followed by oleic acid and stearic acid.[2]
| Fatty acid | Content (%) |
|---|---|
| Palmitic (C16:0) | 49.8–68.1 |
| Oleic (C18:1) | 20.4–34.4 |
| Stearic (C18:0) | 3.9–5.6 |
| Linoleic (C18:2) | 5.0–8.9 |
| Myristic (C14:0) | 1.1–1.7 |
| Lauric (C12:0) | 0.1–0.3 |
Product Specifications
RBD palm stearin quality is set based on free fatty acids, moisture and impurities, iodine value, melting point, and color. PORAM standards list FFA maximum 0.2% and melting point 48–56 °C.[1][2]
| Parameter | Limit |
|---|---|
| Free fatty acids (% as palmitic acid) | Max. 0.1–0.2 |
| Moisture and impurities (%) | Max. 0.1–0.15 |
| Iodine value (Wijs, g I2/100 g) | Max. 48 |
| Melting point (°C) | 44–56 |
| Color (Lovibond cell, red max.) | 3 |
| Peroxide value (meq O2/kg) | Max. 10 |
Fractionation Process
RBD palm stearin is obtained from dry fractionation of RBDPO. The oil is cooled under control so high-melting triglycerides crystallize, then are separated from the liquid fraction by pressure filtration.[2]
Single fractionation yields about 65% olein and 35% stearin. The stearin fraction can be re-fractionated to produce palm mid fraction (PMF) with melting point 35–36 °C suitable for confectionery fat.[3]
Stearin crystals tend to form β′ polymorph, making it suitable for shortening and margarine because it gives fine texture and good stability.[4]
Uses
RBD palm stearin is used as hardstock for trans-free margarine, shortening, and vanaspati formulations. Its semi-solid, stable nature means products do not require partial hydrogenation.[1][2]
In bakery, stearin is used for cake shortening, puff pastry, and bread fat because it provides plasticity, structure, and desired texture. Blends of palm oil and stearin are used for bakery shortening, with solid fat content at use temperature about 15–25%.[4][5]
Outside food, RBD palm stearin is used for soap, wax, and oleochemicals. It is also used in confectionery fat and cocoa butter replacers.[1][4]
Summary
RBD palm stearin is the solid fraction from RBDPO fractionation with FFA maximum 0.2%, iodine value maximum 48, and melting point 44–56 °C. It is rich in palmitic acid and is used as hardstock for margarine, shortening, vanaspati, soap, wax, and confectionery fat.
References
- STA Resources. Refined, Bleached & Deodorized Palm Stearin — specifications and applications. https://www.sta.co.id/products/id
- PalmAzia. RBD Palm Stearin: Melting Point Specifications, Soap Manufacturing & Industrial Fats. https://palmazia.com/blog/rbd-palm-stearin-melting-point-specifications/
- World Bank. Fractionation of palm oil — dry fractionation. https://documents1.worldbank.org/curated/en/479851468182957759/pdf/FAU3.pdf
- Mars Oleochemicals. RBD Palm Stearin — specification and applications. https://www.marsoleo.com/rbd-palm-stearin-malaysia-mars-oleochemicals.html
- Malaysian Palm Oil Board (MPOB). Shortenings Based on Palm Oil Products. https://palmoilis.mpob.gov.my/publications/OPB/opb30-nor2.pdf