The effect of drip loss on drying time during the production of biltong- traditional dried meat product of South Africa

To determine the effect of drip loss on drying time, the favourite dried meat product of South Africa - BILTONG (obtained from beef or game meat) was produced in this study.In standard biltong production, meat slices (1.5 cm thick, cut parallel to the fiber direction) were put in vinegar, marinated and then, hung in the drying cabin. The drying process was stopped when the weight of dried meat slices reached the 50% of their initial weight.In addition to standard production, the beef slices were frozen slowly (1.5 ºC/h) and rapidly (2.5 ºC/h) in order to analyse the effect of drip loss on drying time. After thawing by microwave oven (360W), the beef slices were weighed in order to determine the drip loss; and then they were subjected to the standard production steps.Drying process was achieved in drying cabin by applying one of the two different drying temperature (28ºC (±0.1ºC) and 42ºC (±0.1ºC)).Moisture, fat, salt, ash contents and water activity of the products were measured. The effect of different freezing rates and drying temperatures on the sensory and textural properties (colour, toughness, chewiness, juiceness) were statistically evaluated.The relationships between freezing rates, drip losses, drying temperatures and drying times were established and the effects of these parameters on final product quality were determined.When drip loss amount belonging to beef slices frozen by two different freezing rates were compared, the amount of drip loss was more in slow freezing than that of drip loss in rapid freezing.When the graphs for drying flux ( R ) and free moisture (X) were drawn, the drying curves were similar.When sensory and textural properties were statistically evaluated, the different freezing rates caused an important difference on the colour and the different drying temperatures caused an important difference on the colour, toughness, juiceness. `Freezing rate * Drying temperature? had an important effect on the colour and toughness of beef slices.Key Words: Biltong, Freezing Rate, Drying Rate, Freezing, Drying.