Lakhasly

2.3.1Chemistry CIP relies substantially on the proper usage of chemicals like alkalis, acids, disinfec- tants, and surfactants.A negative performance by increasing alkaline concentration has also been observed when studying other protein- and lipid-based soils like egg yolk [39], and was also found in the study reported in Chapter 6.The common disinfection methods include heating, oxidising solutions (e.g., chlorine- based, iodophors, and peroxide-based) and non-oxidising surfactant-based solutions (e.g., quaternary ammonium compounds, acid anionic, amphoteric disinfectants) [6].The increase in chemical concentration above the optimum can only result in limited improvement of the cleaning efficiency, sometimes even decreased efficiency.For example, Bird et al. (1991, 1992) indicated the existence of an optimal concentration of NaOH (ca.Sodium hydroxide is a commonly used alkaline detergent, supplemented with additives to increase the removal capability to specific soils.Alkaline solutions are mainly used to react with carbohydrate and protein-based soils as well as to make fats and oils soluble.

2.3.1Chemistry
CIP relies substantially on the proper usage of chemicals like alkalis, acids, disinfec-
tants, and surfactants. Alkaline solutions are mainly used to react with carbohydrate
and protein-based soils as well as to make fats and oils soluble. Sodium hydroxide is a
commonly used alkaline detergent, supplemented with additives to increase the removal
capability to specific soils. Acid can dissolve mineral deposits that are introduced by
hard water or heating products. Formulations of acids may contain phosphoric acid and
organic acid (lactic, gluconic, glyconic), etc. Surfactants are added in alkaline and acid
solutions mainly for an anti-foam purpose. Anionic, cationic or non-ionic surfactants are
normally employed as effective surfactants [38].
If a sanitary environment is required, the acid step is generally followed by a disinfection
treatment to kill microorganisms or
decrease the number of microbes to a safe level.
The common disinfection methods include heating, oxidising solutions (e.g., chlorine-
based, iodophors, and peroxide-based) and non-oxidising surfactant-based solutions (e.g.,
quaternary ammonium compounds, acid anionic, amphoteric disinfectants) [6]. Hydrogen
peroxide is a suitable candidate for industrial purposes because the remaining disinfectant
can easily break down into water and oxygen.
Generally, a higher detergent concentration contributes to a higher cleaning rate. How-
ever, an optimal detergent concentration may exist for specific soil materials. The increase
in chemical concentration above the optimum can only result in limited improvement of
the cleaning efficiency, sometimes even decreased efficiency.For example, Bird et al.
(1991, 1992) indicated the existence of an optimal concentration of NaOH (ca. 0.5 wt%)
to clean cooked whey protein [16, 17]. They explained that high alkali concentrations
changed the deposit structure rapidly to form a very thick translucent layer, which was
difficult to remove. A negative performance by increasing alkaline concentration has also
been observed when studying other protein- and lipid-based soils like egg yolk [39], and
was also found in the study reported in Chapter 6.