Laksan is one of the traditional foods of Indonesia. It is consumed with coconut milk sauce. It is usually consumed hot so reheating is sometimes required. Coconut milk, as the main ingredient in laksan sauce, is susceptible to physical and chemical changes when heated. These physical and chemical changes obviously affecst the characteristics of the laksan sauce.
Coconut milk cannot be stored for a long time at room temperature, which is indicated by a quick change in flavor. Heating results in protein de-naturation in coconut milk. This protein denaturation will change the properties and viscosity of the coconut milk if it is heated at 80°C or higher. Heating coconut milk above 80°C makes it susceptible to protein denaturation resulting in unstable conditions of the coconut milk emulsion1, 2.
The longer the heating time, lower the lipid content due to the decrease in fluid during heating. This decrease in fluid accelerates lipid molecule movement, which produces longer distances between lipid molecules and facilitates the release of lipids that are affected by temperature and heating time.
The main component in coconut milk is carbohydrate i.e. sucrose and starch. Heating will cause water absorption into starch granules. High numbers of hydroxyl groups in starch because water initially located outside the starch to become absorbed into starch granules, making them unable to move freely3.
A new study was carried out to analyze the effect of temperature and heating time on the chemical characteristics and proximate contents of laksan sauce. For this purpose analysis of peroxide numbers, free fatty acids, protein content, lipid content, water content and ash content were performed4.
Higher temperatures and longer heating times resulted in higher peroxide numbers in laksan sauce. The highest peroxide number and fatty acid content was found from heat treatment at 80°C for 40 min. There was a significant effect of temperature and heating time on peroxide numbers in laksan sauce found.
The results of this study showed that there was a significant effect of temperature and heating time on the chemical characteristics and proximate contents of laksan sauce. Heating at 70°C produced the best results in terms of protein content, lipid content and carbohydrate content.
Peroxide numbers, free fatty acid, proximate, laksan, traditional food, carbohydrate, coconut milk, heating temperature, protein content, water content, chemical characteristics, protein denaturation, viscosity, to physical and chemical change.
- Raghavendra, S.N. and K.S.M.S. Raghavarao, 2010. Effect of different treatments for the destabilization of coconut milk emulsion. Food Eng., 97: 341-347.
- Peamprasart, T. and N. Chiewchan, 2006. Effect of fat content and preheat treatment on the apparent viscosity of coconut milk after homogenization. Food Eng., 77: 653-658.
- Sukasih, E., S. Prabawati, T. Hidayat and M. Rahayuningsih, 2009. Optimasi kecukupan panas pada pasteurisasi santan dan pengaruhnya terhadap mutu santan yang dihasilkan. Pascapanen, 6: 34-42.
- Hartati, Y., Priyanto, G., Yuliati, K. and Pambayun, R., 2018. Effect of Temperature and Heating Time on Chemical and Proximate Characteristics of Laksan Sauce as a Palembang Traditional Food. J. Nutri., 17: 64-70.