Prevention Of Cap Locking Problem in Syrups by Additives And pH Adjustment Method

Background:Cap locking is a filling problem in sugar syrups. The sugar in the syrup crystallizes on the bottle cap and the threads, making it difficult to remove the cap. The study investigates the inhibition of sucrose crystallization on the bottleneck and cap of sugar syrup-containing products by treating them with various additives and buffers in the manufacturing process. Methodology: Simple syrup (66% w/w sucrose) and partially inverted syrup (in which 66% w/w sucrose was treated with Citric acid, Citric monohydrate, Sodium hydroxide, Buffers (with pH-4, pH-5,and pH-6)) were prepared and observed visually for the crystal growth by spreading on the open Petridishes, Bottle caps, and filled in syrup bottles which were kept at room temperature (25°C). Paracetamol syrup that prepared using simple syrup considered as control syrup product and that was prepared using Citric acid, Citric acid monohydrate , Sodium hydroxide and different buffers were considered as test syrups. The syrups were evaluated for presence of reduced sugars, Viscosity, Surface tension and specific rotation and also visual observation for crystal growth. The Ofners method was used to measure the amount of invert sugar. Observation And Results: No crystal growth was observed for the first 3 weeks in all the formulations. Later 3 weeks crystal growth was observed in the formulation containing citric acid and syrup with pH-6 buffer. No crystal growth was observed in the formulation containing Citric acid monohydrate, Sodium hydroxide and syrup with pH-5, and pH-8 buffers. Hence Paracetamol syrups were prepared by simple syrup, additives and buffers and no crystal growth was observed in the syrups with citric acid monohydrate and citro phosphate buffer of pH 5. . Conclusion: The percentage of invert sugar in all the syrups was determined by Ofner’s method and its viscosity, pH, specific rotation, Surface tension were also determined. The crystal growth was compared in the simple syrup and the invert syrups and observed inhibition of crystal growth in invert syrups prepared by using Citric acid, monohydrate and pH-5 citro-phosphate buffer. Hence the work has concluded that the caplocking can be prevented by adjusting pH and also by adding citric acid monohydrate during manufacturing process.