Feasibility of prolonged frozen-storage of goat milk cheeses is extremely important for profitability and sustainability of the dairy goat industry. Extended frozen-storage can be detrimental to the cheese texture and flavour compounds including organic acids. The study was conducted to evaluate the effects of six months of frozen-storage compared to fresh control on organic acid profiles of soft goat cheese. Three lots of plain soft goat cheeses were purchased and each lot of the cheeses was subdivided into four treatment groups as fresh-unfrozen control (UFC), frozen-thaw control (FZC), 3 and 6 months frozen-storage (3FZ and 6FZ). All samples were subjected to ageing at 4 °C for 0, 14, 28 days. Organic acid concentrations for all known standards ranged 0.01 – 13.0 mg/g cheese. Significant effects were observed for most of the known acids, indicating that some variation in manufacturing parameters might have occurred during cheesemaking. Effects of storage treatments (UFC, FZC, 3FZ and 6FZ) were highly significant for most organic acids, except for orotic and a few unknown acids. Ageing at 4 °C for 4 weeks had little influence on all organic acids except butyric acid. Concentrations of butyric, lactic, propionic, tartaric and uric acids were significantly elevated as the frozen-storage period advanced. The UFC cheese had the highest malic and unknown-11 acids, compared to the three frozen groups. A companion study of sensory properties on the same cheeses revealed that practically no differences existed in sensory values among different storage treatments at 0 day of ageing at 4 °C. Prolonged frozen-storage up to six months may be feasible since no apparent deterioration occurred in sensory scores of the goat cheeses although elevations occurred in several organic acid contents.
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