High-temperature short-time treatment

Further processing after high-temperature short-time treatment and then being left to stand... 

After leaving the press the juice is given high-temperature short-time treatment. Protein is denatured hy the high temperature and is coagulated. After being left to stand for a few hours the protein and the coarse suspended solids are precipitated. The enzymes of the juice are inactivated hy the heat treatment, this being essential for haze stability. 

Compatible with protein-rich beverages (e.g., milk-based soy-based) treated with high-temperature short-time (HTST) pasteurization. However, may be issues with flocculation, thickening, or sedimentation due to Ca-protein interactions when subjected to ultra-high temperature (UHT) heat treatment... 

The effects of heat treatment of milk on the oxidation-reduction potential have been studied to a considerable extent (Eilers et al 1947 Gould and Sommer 1939 Harland et al 1952 Josephson and Doan 1939). A sharp decrease in the potential coincides with the liberation of sulfhydryl groups by denaturation of the protein, primarily /3-lactoglobulin. Minimum potentials are attainable by deaeration and high-temperature-short-time heat treatments (Higginbottom and Taylor 1960). Such treatments also produce dried milks of superior stability against oxidative flavor deterioration (Harland et al 1952). 

Hetrick, J. H. and Tracy, P. H. 1948. Effect of high-temperature short-time heat treatment on some properties of milk. II. Inactivation of the lipase enzyme. J. Dairy Sci. 31, 881-887. 

High-temperature short-time (HTST) treatment (72°C x 15 s) of milk almost completely inactivates the enzyme (Luhtala and Antila, 1968 Andrews et al., 1987 Farkye et al., 1995) so that little if any lipolysis caused by milk lipase occurs in pasteurised milk (Downey, 1974). Somewhat higher temperatures are required for cream pasteurization because of the protective effect of the fat (Nilsson and Willart, 1961 Downey and Andrews, 1966). However, some workers have reported that a more severe heat treatment, [e.g., 79°C x 20 s, (Shipe and Senyk, 1981) or 85°C x 10 s (Driessen, 1987)] is required to inactivate completely milk lipase. 

The inhibition of malo-lactic fermentation can be obtained by SO2 (/w30 mg/liter), maintainance of storage temperature at less than 18°C and adjustment of pH to at least below 3.3. Killing or removing the bacteria from wine is a more definite step to stabilize wine against malo-lactic fermentation. Pasteurization and particularly HTST treatment (high temperature, short time -98 C for one second - with rapid cooling) is often used. Sterile filtration has also been used with 0.45 (un membrane filters. 

A high maximum temperature ( 1100°) is found to give the best yield of the products. The lowest temperature that yields InsS4 is 650°. To isolate the reaction products from the tin matrix, the chunks of reacted material are treated with concentrated hydrochloric acid. To reduce the attack on the crystals, short-time treatments with acid are alternated with acetone washings. 

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