Impact of storage at room temperature on the properties of CiP solutions

Abstract

This work reports the analysis of cleaning solutions used in cleaning in place (CiP) and the changes that occur during storage at room temperature. Tests were performed on different solutions used to clean brewhouse vessels and a mash filter in a local brewery. The solutions were collected from CiP tanks after regeneration and were stored for three months in darkness at room temperature. Over time, the physical, chemical and microbiological parameters of the cleaning solutions were analysed. At the end of the study, the solutions were evaluated in terms of surface wetting and cleaning capability. The results showed that storage of the solutions at room temperature contributed to the agglomeration of particulates into larger conglomerates that may contribute to clarification of cleaning solutions by sedimentation. However, other parameters of the stored CiP solutions did not change. © 2019 The Institute of Brewing & Distilling

Predictive Model for the Surface Tension Changes of Chemical Solutions Used in a Clean-in-Place System

“…value of about 0.1-2.0% after 12 consecutive weeks of use. This was consistent with previous reports by the authors [24]. In the literature, this phenomenon is explained by the hydrolysis of fat and proteins in the post-production deposits, which in the presence of NaOH produced surfactant molecules (soap), which lowered the surface tension [3,21,23,27].…”

“…The industrial acidic solution H 3 PO 4 + HNO 3 (T) had a different surface tension (about 30% lower) compared to the 1% standard solution H 3 PO 4 + HNO 3 . This result was consistent with previous reports [24,28], and may have been a consequence of inadequate inter-operative rinsing between alkaline and acidic cleaning, resulting in the passage of residual NaOH solution into the H 3 PO 4 + HNO 3 solution. After 12 weeks of storage, this solution showed an approximate 8% increase in surface tension values, which is consistent with the results for its reference counterpart.…”

“…= f(t) was shown by a logarithmic function (Figure 3b-d), which was in agreement with the results of other authors [24]. The distributions of the dependent variables were used as assumptions for the development of the final model, which described the relation d to disassemble it.…”

“…HCl and NaOH, Chempur, PiekaryŚląskie, Poland). The reactions and calculation of % concentration of individual solutions were performed according to the method presented by Piepiórka-Stepuk et al [24]. The analyses of solutions at the initial and final storage periods were performed in triplicate.…”

“…On the other hand, the lowering of the acidic solution's surface tension was explained by an inadequate inter-operational rinsing between alkaline and acidic cleaning, which resulted in the transition of residual NaOH to H 3 PO 4 + HNO 3 solution. In addition, studies of agents collected from a brewery showed that these solutions exhibited reduced cleaning ability compared to their initial solutions [24]. The question, therefore, is whether changes in the surface tension of cleaning solutions occur solely as a result of reacting with deposits eluted from production installations or are also a result of the so-called aging of solutions during storage.…”