The effects of integrated ultrasonic infrared frying (USIF) on the oil absorption of apple slices and the oil deterioration were studied with frequency of 28 and 40 kHz, respectively. Results showed that the heat transfer and moisture migration was accelerated by the integrated ultrasound in IF. The soluble Gal-A content and esterification degree of pectin was increased, the damages of pectin crystal structure and chemical structure in side chain was aggravated. These damages to pectin were intensified with higher frequency (40 kHz) of ultrasound. Lower retention of phenols was found in USIF apple slices, but the flavonoids content had no significant change compared to CF samples. USIF samples showed a smoother morphology, and the pore volume and porosity were reduced by ultrasonication applied with 28 kHz but increased with 40 kHz. The largest volume fraction of pores was changed from 100-250 μm in IF to 0.02–10 μm and 10–100 μm by the integrated ultrasound at 28 kHz and 40 kHz samples, respectively. The total oil uptake in USIF samples was reduced by 24.9 %–33.2 % compared to the conventional fried (CF) samples, and achieved the lowest with the frequency of 40 kHz. The surficial and structural oil were also decreased by 39.2 %-51.3 % and 20.9 %–32.3 %, respectively. The peroxide value, acid value, carbonyl value, polar component, and the saturated fatty acids ratio of oil in repeated frying for 16 h was reduced in USIF, especially with ultrasonication 40 kHz. These results indicate that USIF is a promising method for producing novel low-oil apple fries.

中文翻译：

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通过红外线油炸中集成的超声波减少油炸苹果片的吸油和油变质


以 28 kHz 和 40 kHz 的频率研究了集成超声红外油炸 （USIF） 对苹果片吸油和油变质的影响。结果表明，在 IF 中集成超声加速了传热和水分迁移。果胶的可溶性 Gal-A 含量和酯化度增加，果胶晶体结构和侧链化学结构的损伤加剧。这些对果胶的损害随着超声频率的升高 （40 kHz） 而加剧。USIF 苹果切片中酚类物质的保留率较低，但与 CF 样品相比，黄酮类化合物含量没有显着变化。USIF 样品表现出更光滑的形貌，28 kHz 超声处理后孔隙体积和孔隙率降低，但 40 kHz 时孔隙率增加。在 28 kHz 和 40 kHz 样品下，通过整合超声，IF 中孔的最大体积分数从 100-250 μm 分别变为 0.02-10 μm 和 10-100 μm。与传统油炸 （CF） 样品相比，USIF 样品的总吸油量降低了 24.9 %–33.2 %，并且在 40 kHz 的频率下达到最低。表层油和结构油也分别减少了 39.2 %-51.3 % 和 20.9 %-32.3 %。在 USIF 中，重复油炸 16 h 的过氧化值、酸价、羰基值、极性成分和饱和脂肪酸比降低，尤其是超声处理 40 kHz。这些结果表明，USIF 是生产新型低油苹果薯条的一种很有前途的方法。