Abstract:

Comparison of three different drying methods, air blowing, vacuum drying and shade drying was carried out for
Allium macrotemon Bunge. bulbs. For this, we determined the contents of saponion and sugar in the dried bulbs as well as
the drying rate and energy consumption for the drying methods. The results showed that sucrose was the most abundant
and xylopyranose the least abundant sugar in the dried bulbs of Allium macrotemon Bunge.. The content of sapinion
reached the maximum level of 34.60 mg/g in the air-blowing dried sample at 80 ℃ and the maximum sucrose content of
40.82 mg/g was also attained by this drying method at 60 ℃. However, vacuum drying resulted in the maximum levels of
glucuronic acid and galacturonic acid (5.12 and 300.65 μg/g, respectively). The contents of arabinose and soluble sugars
were relatively stable among different drying methods. Higher drying temperature led to higher drying rate. Considering
processing characteristics and retention of effective components, air drying at 80 ℃ is the best drying method for Allium
macrotemon Bunge. bulbs.

Key words: Allium macrotemnon Bunge. bulbs, drying methods, spanion, sugar