Accelererat åldrande av produkter Apelsinjuice och hallondryck

Sammanfattning: Brämhults Juice AB is one of Sweden’s leading producers of fresh fruit juices and drinks. The fruit drinks last 3 days once opened and when stored in a refrigerator kept at 7°C. Since factors that shorten the drinks’ best before date are usually not noticed until the entire batch has expired, it would be advantageous to find a way to accelerate the drinks’ natural deterioration, so that an unusal short best before date is noticed before more products are shipped off to the stores. This was achieved by establishing the present microorganisms’ (presumably only Candida yeasts) optimal growth conditions (25°C), inoculating drink samples on a special type of agar that inhibits bacterial growth, spreading them out on the agar using sterile spreaders and eventually storing these drink samples in said ideal enviroment, so that the yeasts would grow at an increated rate and thus spoil the drinks prematurely. The cells were counted using viable count. In doing this, the drinks aged and reached the maximum allowed amount of colony forming units/ml in a matter of 1-2 days, rather than the 3 days it usually takes. While storing the samples at the optimal growth temperature is believed to have had the greatest impact on Candida growth rate, the presence of oxygen is also thought to have mattered, though exactly how much is unknown. Additionally, batch and product sample variety played a role, making it difficult to obtain consistent values throughout the laboration.