Therdthai N, Soontrunnarudrungsri A, Khotchai W
Department of Product Development, Faculty of Agro-Industry, Kasetsart University, Bangkok 10900, Thailand.
Heliyon. 2023 Jan 20;9(2):e13093. doi: 10.1016/j.heliyon.2023.e13093. eCollection 2023 Feb.
Due to the high global consumption of eggs, eggshell has become as one of the top domestic, agricultural and industrial wastes. This study determined eggshell characteristics after boiling at 95 °C and steaming at 121 °C, with additional heat treatments using hot air at 200 °C, microwaving at 900 W and infrared at 1050 W. Boiling in water for 60 min inhibited spoilage and pathogenic microorganisms that was the equivalent of steaming at 121 °C for 15 min. Scanning electron microscopy revealed that heat treatments on dried eggshell power modified the pore size and the accumulation of particles on the powder surface. From the X-ray diffraction pattern, all eggshell powder samples presented a peak at 29.40° demonstrating a crystallographic lattice of calcium carbonate with crystallinity in the range 90.20-91.05%. The calcium releasability of the control sample was 205.17-208.40 mg/L. Further treatment using hot air for 10-20 min increased the calcium releasability of the boiled and steamed eggshell powders to 219.95-225.50 and 230.35-305.20 mg/L, respectively while the microwave treatment for 2 min increased the calcium releasability of the boiled and steamed eggshell powders to 230.85 and 244.60 mg/L, respectively. The infrared treatment did not improve the calcium releasability of the sterilized eggshell powders. Up to 2% eggshell powder could be added to the dog biscuit dough. The fortified calcium biscuits contained 507.12 mg calcium/100 g of biscuit, while the Ca-to-P ratio was 1.94:1, which is within the recommended range for dog food.
由于全球鸡蛋消费量巨大，蛋壳已成为国内、农业和工业领域的主要废弃物之一。本研究测定了鸡蛋在95℃水煮、121℃蒸煮后的特性，并进行了额外的热处理，包括200℃热风处理、900W微波处理和1050W红外处理。在水中煮60分钟可抑制腐败菌和致病微生物，效果等同于在121℃蒸煮15分钟。扫描电子显微镜显示，对干蛋壳粉进行热处理会改变孔径以及粉末表面颗粒的堆积情况。从X射线衍射图谱来看，所有蛋壳粉样品在29.40°处都有一个峰，表明碳酸钙的晶体晶格，结晶度在90.20 - 91.05%范围内。对照样品的钙释放率为205.17 - 208.40mg/L。进一步用热风处理10 - 20分钟，可使水煮和蒸煮后的蛋壳粉的钙释放率分别提高到219.95 - 225.50mg/L和230.35 - 305.20mg/L，而微波处理2分钟可使水煮和蒸煮后的蛋壳粉的钙释放率分别提高到230.85mg/L和244.60mg/L。红外处理并未提高杀菌后蛋壳粉的钙释放率。在犬用饼干面团中可添加高达2%的蛋壳粉。强化钙饼干每100g饼干含507.12mg钙，钙磷比为1.94:1，在犬粮推荐范围内。
