Flavor Maintenance And Antioxidation Of Cushions

Cushions, a kind of Chinese-style leisure food, have become more and more popular dueto its deliciousness and convenience. Cushions contain a lot of lipid. Lipid oxidation andauto-oxidation are one of the major causes of deterioration, which directly results in thedevelopment of a stale or rancid flavour. Also, the volatile flavor components of Cushionseasily lose during the storage. Therefore, prevention of lipid oxidation has become one of thebiggest technical challenges facing the Cushions maker. This paper studied the changes andthe way to improvements of the qualities of Cushions during the shelf life.Firstly, this paper studied on the Rancimat method and the Schaal oven method for thedetermination of the oxidation stability of peanut oil and peanut butter, and also analysed thecorrelation between the two methods. Results showed that, using the Rancimat method toreplace the traditional evaluation of peroxide value to determine the oxidation stability ofpeanut oil and peanut butter is feasible. The conditions of Rancimat method were as follows:test temperature100～150℃, gas flow20L/h and sampling weight3g.The volatile flavor components from peanut buffer and Cushions were studied, and itsvolatile components were extracted and determined by solid phase micro extraction-gaschromatography-mass spectrometry (SPME-GC-MS). Among these flavor components, themajor volatile components were aldehydes. The relative percentage of the key odorcompounds,2-methyl butanal and Isobutyraldehyde, decreased significantly after1month ofstorage, while, the relative percentage of hexanal increased. Through study the relationship ofinduction time and flavor changes during the storage, it was concluded that the oxidation oflipid deterioration is the main factor leading to the quality variation of peanut buffer andCushions.Rosemary extract, tea polyphenol, phytic acid and ascorbyl palmitate were selected toprepare natural antioxidant compound for Cushions due to their antioxidant capacity and thesynergistic effect. According to the range analysis of orthogonal test design’s results and thepractical production experience, the optimum formula of the natural antioxidant compoundwas as follows: Rosemary extract0.063%, tea polyphenol0.0024%, phytic acid0.0004%, ascorbyl palmitate0.0004%.Addition of natural antioxidants compound and liquid soybean lecithin together affectedlipid oxidation during Cushions storage. Natural antioxidants compound and liquid soybeanlecithin used together had an inhibitory action on lipid oxidation and extended the inductionperiod and the shelf life of Cushions. The optimum formula was as follows: Rosemaryextract0.063%, tea polyphenol0.0024%, phytic acid0.0004%, ascorbyl palmitate0.0004%,liquid soybean lecithin0.5%. The antioxidant capacity of this compound was stronger thanTBHQ.