微波热烫和气调包装对中央厨房用胡萝卜理化特性及品质的影响

Influence of Microwave Blanching and Modified Atmosphere Packaging on Physiochemical Properties and Quality of Carrot Used

摘要:

胡萝卜经去皮、切分等加工后容易受到氧气和微生物的作用而发生腐败变质，因此，需要合适的保鲜方法延缓其品质劣变。作者研究微波热烫和气调包装对鲜切胡萝卜贮藏品质的影响。对胡萝卜进行微波热烫和气调包装处理后，每隔5 d测定胡萝卜样品的硬度、β-胡萝卜素质量分数、水分质量分数、水分活度、水分状态、过氧化物酶活性、颜色和微生物数量等指标。微波热烫可以有效降低胡萝卜中的微生物数量，并降低其水分迁移率。相比之下，对照样品中自由水（T₂₄）的质量分数更为突出。360 W微波热烫300 s结合高氧气调包装（体积分数80% O₂、10% CO₂、10% N₂）降低了储藏期内胡萝卜中β-胡萝卜素的降解、硬度的损失和过氧化物酶的活性，且更好地控制了胡萝卜中水分活度和水分质量分数的增加。低功率微波热烫结合高氧气调包装是一种有效的保鲜方法，可用于改善胡萝卜的储藏品质。

Abstract:

Carrots are susceptible to spoilage by oxygen and microorganisms after peeling and cutting. Therefore, appropriate preservation methods are needed to delay their quality deterioration. In this study, microwave blanching and modified atmosphere packaging (MAP) used as preservation methods and their effects on the quality of carrots during storage were investigated. After the treatment of microwave blanching and modified atmosphere packaging, the firmness, β-carotene content, moisture content, water activity, moisture status, peroxidase activity, colour, and microbial load of carrots were evaluated in an interval of 5 days. Microwave blanching effectively reduced the microbial load and decreased water mobility in carrot. In contrast, free water (T₂₄) was more prominent in the control sample. Microwave blanching under 360 W for 300 s combined with modified atmosphere packaging (80% O₂,10% CO₂, 10% N₂) reduced the degradation of β-carotene, loss of firmness and peroxidase activity of carrots during storage, and the increases of water activity and moisture content were better controlled. Low power microwave blanching combined with high oxygen modified atmosphere packaging is an effective preservation technology which could be used to maintain and improve the storage quality of carrot.