The effects of tempering temperature were evaluated on the physical behavior of palm oil-based margarine during various storage conditions. The physical properties were characterized based on hardness, rheological property, instant solid fat content, microstructure, thermal stability and polymorphic forms. The samples tempered at 20℃ had poor spreadability and post-hardening occurred during storage. Though the spreadability of the samples was best at 30℃;however,the samples were ingeneral too soft with also poor thermal stability; while sandiness happened and the β form crystal became the mass crystallization forms after three weeks storage under temperature cycles. When the tempering temperature was 25℃ ,the samples had a proper solid fat content profile,hardness,and spreadability,with also a stable crystallization network,mean while the stability is better and the crystals mostly present as β form under temperature cycles during storage. The study also indicates that the stable tempering temperature is critical. Slight temperature variation such as up to 5 ℃. can lead serious difference of the product properties.%研究了熟化温度对棕榈油基人造奶油质构、流变特性和结晶特性的影响,主要包括对产品储藏及其温度波动过程中硬度、流变特性、即时固体脂肪质量分数、微观形态、热稳定性和晶型的影响,结果表明:熟化温度为20℃的样品在储藏过程中出现后结晶现象,且其涂抹性最差；熟化温度为30℃的样品,虽然涂抹性较好,但其硬度较小,温度波动21 d后发生起砂,且大量转化为β晶型；熟化温度为25℃的样品具有合适的固体脂肪质量分数,完善的结晶网络,良好的硬度和涂抹性能,且其抵抗温度波动的能力较强,能够较长时间的维持β'晶型.研究也表明,稳定的熟化温度是很重要的,即便5℃的差异也会造成产品性能的显著差异.
展开▼
