The textural properties of cheese samples with different hardness, including three kinds of hard cheeses and two kinds of soft cheeses, were measured by using a texture analyzer and the rheological parameters of the same samples were evaluated by using a rheometer to compare the rheological and textural properties of all the cheeses. Result showed that there was a significant difference in physicochemical properties (P ＜ 0.05), including pH, moisture content and water activity, between hard and soft cheeses. Hardness was significantly higher in hard cheeses than in soft cheeses. Hardness of all the cheeses obtained by TPA analysis correlated well with viscoelastic moduli. The dynamic analysis showed that all these cheeses manifested a more solid-like form. The rheological parameters were dependent on the oscillatory frequency. The differences of viscoelastic moduli between soft and hard cheeses were probably attributed to different amounts of moisture content and different levels of proteolysis. Hard and soft cheeses were significantly different through texture and rheology analysis. Viscoelastic moduli in the frequency range of 0.1 to 75 Hz could be used as a measure to distinguish among five kinds of cheeses.

The present study aimed at understanding the storage stability of bovine colostrum whey powder. Moreover, a predictive equation to estimate its shelf life under the conditions of ambient temperature (25 ℃), 50% relative humidity (RH) and packaging in PET bags was presented. The evolution of some key physicochemical and biochemical parameters was studied over a storage period of 90 days. The results obtained in this study indicated that the contents of water and HMF and TBA value in bovine colostrum whey powder packaged in PET bags significantly increased over time during the storage period (P ＜ 0.05) and color difference also showed an increasing trend, even though with some fluctuations, while IgG level conversely exhibited a decreasing trend in the first 60 days, followed by no significant decrease. Under the storage conditions used in this study, the shelf life of bovine colostrum whey powder was 99.40 days. The findings of this study can provide basic data for industrial production of bovine colostrum whey powder.