基于流变特性评价3个苹果品种果肉质地

Texture and quality evaluation of three apple cultivars based on rheological properties

研究了3个典型不同质地苹果品种‘嘎拉’‘华月’‘富士’果肉流变特性的差异,以便为果实采后、贮运、加工提供理论依据。采用质构仪TMS-PRO对3个品种果实质地进行蠕变和应力松弛试验,建立苹果果实的蠕变特性四元件伯格斯模型(Burger’s Model)和应力松弛特性三参数的广义Maxwell模型,对蠕变和松弛参数进行了相关性分析和主成分分析。蠕变和松弛参数货架期变化趋势能够区分不同品种果实的流变特性组织结构差异。‘华月’TPA果肉硬度在货架期较‘嘎拉’和‘富士’下降最多,蠕变、松弛特性相关的黏性和弹性参数也都下降最快,‘嘎拉’次之,‘富士’下降最慢,这说明了苹果果肉硬度、弹性、黏性呈正相关。通过3个苹果品种蠕变、松弛特性参数的相关性分析和主成分分析也反映了苹果果肉流变特性是弹性因子和黏性因子共同作用。研究结果为苹果贮藏、运输和加工提供数据支持和理论依据。

AAbstract The creep and stress relaxation of fruit pulp were measured by texture analyzer TMS-PRO using ’Gala’, ’Huayue’ and ’Fuji’. The creep and stress relaxation of fruit pulp of three apple varieties with different storability were tested during shelf life. The fruits of three apple varieties were harvested at 9 ripening time. By establishing a four-element Burger’s model and a generalized Maxwell model with three parameters of stress relaxation, the initial elastic coefficient E1, delayed elastic coefficient E2, delayed timeτ, viscous coefficient η1, viscous coefficient η2, decay elastic modulus E1’, equilibrium elastic modulus Ee, zero-time elastic modulus E0 and relaxation of the creep parameters were obtained. Time T, viscous coefficientη, and through correlation analysis and principal component analysis of creep and relaxation parameters. It is proved that the creep and relaxation parameters can reflect and distinguish the rheological properties of different apple varieties and reveal the difference of microstructure in different apple varieties. Compared with ’Gala’ and ’Fuji’, the pulp hardness of ’Huayue’ TPA decreased the most during the shelf life, and the viscosity and elasticity parameters related to creep and relaxation properties also decreased the fastest, followed by ’Gala’ and ’Fuji’, which showed that the hardness, elasticity and viscosity of apple pulp were positively correlated. The correlation between the parameters of relaxation and creep characteristics is different. The principal component analysis(PCA) also showed that the rheological properties of apple pulp was an elastic factor and a viscous factor, and the contribution rate was equal. The results provide data support and theoretical basis for apple storage, transportation and processing.