Rheological and Sensorial Characteristics of the Reformed Ras Cheese Made Using Cheese Trims and Different Starches

Abstract

The objective was to study the technological suitability of using the Ras cheese trims and starch as casein stabilizer in making novel reformed Ras cheese (RRC) product and to evaluate the effect of two levels of corn, potato, and rice starches whether at the native form or pregelatinized, on the rheological and sensorial properties of that reformed Ras cheese which was supposed to be very close to conventional Ras cheese. Cheese trims were shredded, and table salt was added and kept at 25°C for 24 h. Starch was added in the form of whipped transparent paste, then the mixture was cooked without emulsifying salts to 75°C for 5 minutes at 120 rpm, the cooking temperature was then lowered until reaching 55°C at the same stirring speed, and then, the mixing speed was raised to 1400 rpm for another 1 minute. The molten cheese mass was poured into custom-made moulds. The height from which the cheese was poured into moulds was adapted to be 50 cm from the bottom of the mould. The samples were allowed to set at 5°C for 24 hours. The obtained results indicated that increasing the starch level significantly decreased the values of dry matter, protein, lactose, titratable acidity, water activity (aw), consistency coefficient ( $K$ ), flow behavior index ( $n$ ), Tan δ, hardness, springiness, melt distance, and shredding efficiency and increased the values of ash, pH, critical strain, adhesiveness, and sliceability. The starch source had no significant effect on critical strain, $K$ , Tan δ, and sliceability. The rice starch RRCs were distinguished with the highest significant values of aw, $n$ , cohesiveness, springiness, flavour, and total sensorial scores. The potato starch RRCs had the lowest hardness, fracturability, shreddability, and total sensorial score, as well as the highest melt distance, free oil, and adhesiveness. The corn starch RRCs were characterized with the lowest aw, $n$ , springiness, body, and texture scores, as well as the highest hardness, fracturability, and shreddability. The pregelatinized starch RRCs were associated with increased aw, critical strain, $n$ , Tan δ, fracturability, springiness, melt distance, shredding efficiency, sliceability, and all sensorial characteristics except appearance. The native starch RRCs were characterized with the highest pH, hardness, adhesiveness, free oil, and appearance score values.