不同热风干燥温度对方竹笋品质的影响

吕朝燕; 高智席; 马秀情; 李敏; 张柏林; 蔡致广; 蔡春

doi:10.13386/j.issn1002-0306.2020070253

不同热风干燥温度对方竹笋品质的影响

Effect of Different Hot Air Drying Temperatures on Quality of Chimonobambusa quadrangularis Shoots

摘要

摘要: 为了明确温度对热风干燥方竹笋干品质的影响，通过设置不同温度（65、75、85、95 ℃）处理，研究了其对方竹笋干含水率、色泽、复水比、总糖、还原糖、可溶性蛋白、游离氨基酸以及感官评分等的影响。结果表明：方竹笋含水率随干燥时间的增加而快速下降，温度越高，下降速度越快；方竹笋干亮度（L^* ）值、红度（a^* ）值和黄度（b^* ）值均随干燥温度的升高呈先增大后减小的趋势，而色差（∆E）值呈先减小后增大的趋势，75 ℃处理最小为15.47±3.94；方竹笋干复水比随复水时间增加而增大，到基本不再增加时，复水比由大到小依次为75 ℃>85 ℃>65 ℃>95 ℃，75 ℃处理复水比最大为6.11±0.44；方竹笋干总糖、可溶性蛋白和游离氨基酸含量均随干燥温度升高而降低，95 ℃处理较65 ℃处理分别减少了1.23%、2.67%、0.71 μg/100 g；方竹笋干还原糖含量随温度升高先增大后减小，75和85 ℃处理高于65和95 ℃处理且差异显著（P<0.05）；同时，方竹笋干感官评分的总分呈先增大后减小的趋势，75 ℃处理综合评分最高为86.30±3.92分，显著高于其它处理（P<0.05），达到一级分类标准。可见，75 ℃热风干燥处理在保证较快干燥速率的同时，更有利于保持方竹笋干的营养和感官品质及复水性能，该温度是方竹笋热风干燥加工的适宜温度。

Abstract: In order to clarify the effect of temperature on the quality of Chimonobambusa quadrangularis shoots dried by hot air, different temperatures (65, 75, 85, 95 ℃) were set. The effects of temperature on moisture content, color, rehydration ratio, total sugar, reducing sugar, soluble protein, free amino acid, as well as sensory score, were studied. The results showed that the moisture content of bamboo shoots decreased rapidly with the increase of drying time, the higher the temperature, the faster the decline rate. The brightness (L^* ) value, redness (a^* ) value and yellowness (b^* ) value of dried bamboo shoots all increased first and then decreased with the increase of drying temperature, while the color difference (∆E) value decreased first and then increased later, the minimum value of 75 ℃ treatment was 15.47±3.94. The rehydration ratio of dried bamboo shoots increased with the rehydration time. When it basically did not increase, the rehydration ratio was 75 ℃>85 ℃>65 ℃>95 ℃ in order from large to small, and the maximum rehydration ratio of 75 ℃ treatment was 6.11±0.44. The content of total sugar, soluble protein and free amino acid of dried bamboo shoots decreased with the increase of drying temperature. Compared with 65 ℃ treatment, the contents of 95 ℃ treatment decreased by 1.23%, 2.67%, 0.71 μg/100 g, respectively. The reducing sugar content of dried bamboo shoots increased first and then decreased with the increase of temperature. The 75 and 85 ℃ treatments were higher than the 65 and 95 ℃ treatments and the difference was significant (P<0.05). At the same time, the dried bamboo shoots’ comprehensive score of the sensory score increased first and then decreased. The highest comprehensive score of 75 ℃ treatment was 86.30±3.92 points, which was significantly higher than other treatments (P<0.05) and reached the first classification standard. It can be seen that the hot air drying treatment at 75 ℃ is more conducive to maintaining the nutritional and sensory quality and rehydration performance of the dried bamboo shoots while ensuring a faster drying rate, which is an appropriate temperature for the hot air drying processing of the bamboo shoots.