摘要
真空冷冻干燥能够较好地保留蓝莓中花色苷、维生素等营养功能物质,但蓝莓内部水分在真空冷冻干燥过程中难以透过表皮的致密蜡质层向外扩散,进而引发结构塌陷,导致产品存在表皮皱缩、空心、汁液流失等严重缺陷,限制了真空冷冻干燥技术在蓝莓干燥领域的应用。为改善真空冷冻干燥后的蓝莓品质,研究了Na2CO3溶液浸泡时间(3、10、30 min)、削皮部位(顶部、底部、顶部和底部)、打孔数目(12、14、36孔)和划痕数目(2、8、16道)对真空冷冻干燥蓝莓干燥特性、吸湿性及质构、色泽和香气等感官品质的影响。结果表明:与未预处理的真空冷冻干燥蓝莓相比,打孔和划痕预处理均可有效避免蓝莓组织塌陷和皱缩,但Na2CO3溶液浸泡和削皮处理组品质较差;打孔(36孔)和划痕(16道)处理的真空冷冻干燥蓝莓外观及其微观结构保持完整,干燥时间分别减少6 h和4 h,脆度分别提高31.55%和4.06%,外观及内部结构均无明显皱缩和塌陷,色泽和香气接近新鲜蓝莓。研究旨在为真空冷冻干燥技术制备高品质蓝莓整果粒提供一定的参考依据。
Freeze drying can better retain nutritional and functional substances in blueberries such as anthocyanins and vitamins.However,it is difficult for internal water to diffuse outward through the dense waxy layer of the blueberry epidermis during the freeze drying process,which triggers structural collapse as well as a series of serious quality defects of products,including epidermis shrink,hollowness,and juice loss.These limited the application of the freeze drying technology in the field of blueberry drying.To improve the quality of freeze-dried blueberries,the influence of pretreatment with soaking in Na 2CO 3 solution(3,10,30 min),peeling(top,bottom,top and bottom),punching(12,14,36 holes),and cutting epidermis(2,8,16 incisions)on the drying characteristics,hygroscopicity,and sensory qualities such as texture,color and aroma of freeze-dried blueberry were investigated.The results indicated that compared with non-pretreated freeze-dried blueberries,both punching and cutting epidermis treatment could effectively avoid the collapse and shrink of freeze-dried blueberries,which obtained better quality than the treatment of soaking in Na 2CO 3 solution and peeling.Among them,the freeze-dried blueberries with punching(36 holes)and cutting epidermis(16 incisions)remained their intact appearance and microstructure with reduced drying time by 6 h and 4 h,respectively.Meanwhile,the brittleness was increased by 31.55%and 4.06%,respectively.There was no obvious shrink and collapse of epidermis and interior structure in these two processed blueberries,and the color and aroma were closer to the fresh blueberries than that of other treatments.This study aimed to provide a guiding reference for the preparation of high-quality whole blueberry fruits by freeze drying.
作者
李原
毕金峰
马有川
冯舒涵
郭玉霞
易建勇
LI Yuan;BI Jinfeng;MA Youchuan;FENG Shuhan;GUO Yuxia;YI Jianyong(Institute of Food Science and Technology,Chinese Academy of Agricultural Science/Key Laboratory of Agro-Products Processing,Ministry of Agriculture and Rural Affairs,Beijing 100193,China)
出处
《食品科学技术学报》
EI
CAS
CSCD
北大核心
2023年第2期175-186,共12页
Journal of Food Science and Technology
基金
国家重点研发计划项目(2022YFD1600700)
中国农业科学院科技创新工程项目(CAAS-ASTIP-2020-IFST-04)。
关键词
真空冷冻干燥
蓝莓
预处理
质构
多孔结构
freeze drying
blueberry
pretreatment
texture
porous structure
