Study on drying quality of corn by hot air and microwave drying

Absrtact: Colour, crack rate, peroxidase activity, malondialdehyde and fatty acid value were selected as evaluation indexes to study the drying quality of Maize by hot air combined with microwave drying. At the same time, the different quality indexes of samples dried by hot air at 60 C and microwave at 119W were compared and analyzed, and the quality of corn dried by different microwave drying equipments was evaluated by fuzzy comprehensive evaluation. The results showed that the quality of corn dried by combined drying was better than that dried by hot air alone, and its quality was closer to that dried by microwave alone. .

Key words: combined drying; microwave assisted; microwave drying corn; quality; fuzzy comprehensive evaluation

Drying corn is an important part of maize before storage. At present, there are many studies on maize drying at home and abroad, aiming at eliminating the problem of maize quality decline in the drying process as far as possible. The combined drying technology is one of the hotspots of drying technology at present. The combined drying of hot air and microwave not only solves the problems of long drying time and great influence on material quality deterioration, but also solves the problems of high cost of microwave drying, material overheating and quality deterioration.

Therefore, this paper studies and analyses the quality of corn drying by hot air combined with microwave, and compares the quality of samples dried by hot air alone and microwave alone, and uses fuzzy comprehensive evaluation for different quality indicators, so as to provide some reference for the research of corn drying quality storage.

Through testing and comparative analysis of quality indexes of Maize in three different drying methods, it can be seen that the color acceptability of combined drying maize is higher than that of single microwave drying, its POD activity is also significantly higher than that of single microwave drying, and its crack rate and MDA are lower than that of single hot air drying. The results show that the quality of maize after combined drying is better than that of single microwave drying. It is superior to single hot air drying sample, and its quality is closer to individual microwave drying sample.

According to the results of the fuzzy comprehensive evaluation, the quality of the combined drying corn is better than that of the single hot air drying sample, and its quality is close to that of the single microwave drying sample. At the same time, it shows that the application of the fuzzy comprehensive evaluation can objectively and accurately reflect the quality of corn.