Effect of Temperature on Sorption Isotherms and Thermodynamics of Intermediate Moisture Category Indian Milk Product Cham-cham

Abstract

Cham‐cham, a traditional Indian milk product prepared by heat and acid coagulation of milk, has a shelf life of a few days. Its storage stability could be studied by monitoring the changes in water activity at different temperatures and humidity. Hence, moisture sorption characteristics of cham‐cham were determined at three temperatures i.e., 5, 25 and 40C to obtain sorption isotherms. The data obtained were fitted to several models in which BET (Brunauer–Emmett–Teller), Modified Mizrahi and Henderson model gave best fit. From the BET equation, monolayer moisture content calculated at 5, 25 and 40C were 24.27, 15.60 and 18.25%, respectively. Density of sorbed water, number of adsorbed monolayers, percent bound water and surface area of adsorbent were calculated. The porosity of cham‐cham increased with increase in temperature. The net isosteric heat of sorption decrease exponentially with increasing moisture content and enthalpy–entropy compensation theory confirmed the process to be spontaneous and enthalpy driven. Practical Applications The equilibrium moisture content, monolayer moisture content, net isosteric heat of sorption and related properties calculated can be used to represent the state of water present in cham‐cham at different temperatures for physicochemical and microbiological changes. These results could successfully be utilized in predicting water activity values of cham‐cham at different temperature and moisture content. The predicted water activity values may prove successful in studying and enhancing the shelf life of cham‐cham by designing the production process and packaging material for cham‐cham making and packaging.

Sorption isotherms and thermodynamic properties of the dry silage of red tilapia viscera (Oreochromis spp.) obtained in a direct solar dryer

“…This coincides with what Zuo et al. (2015) and Puri and Khamrui (2016) found in protein-rich matrices. They found that the trend for increased water sorption with increased temperatures is due to a complex association between food components and water vapor that can vary according to temperature and the value of a w .…”

Thermodynamic analysis of Experimental Sorption isotherms of dietetic Chhana Kheer

“…Results indicate stronger interactions between the chhana kheer and water vapour at low moisture content, finally leading to large Q st values. Similar observations have been made by Deshmukh et al [3] in kalakand and Puri and Khamrui [7] in cham-cham.…”

“…Water activity plays a vital role in spoilage of foods, determining the shelf-stability and deteriorative mechanisms in food systems. Several scientists have reported and ISSN: 2577-4182 published moisture sorption isotherms of various dairy products such as kalakand [4], banana shrikhand [5], bottle gourd burfi [6], cham-cham [7], sandesh powder [8], mexican mennonite-style cheese [9] and dietetic rabri [10] at various temperatures.…”

Effect of particle size and temperature on the hygroscopic behaviour of cassava flour from dry group and storage time estimation

“…A decrease in the flour's hygroscopicity was observed when increasing temperature, which was evident in the a w intermediate region and more representative for the desorption process (Figure 2). This behaviour is attributed to the fact that a change in temperature changes the mobility of water molecules and consequently the thermodynamic equilibrium between the vapour phase and the adsorbed phases (Puri & Khamrui, 2016). As the temperature increases, the water molecules are activated due to an increase in the energy level, which become less stable and the bonds between them and the active sites of the product become easier to break (Flores-Andrade, Beristatin, Vernon-Carter, Gutiérrez, & Azuara, 2009).…”