Effects of enzymatic treatment of pomace and processing method on drying time, particle size distribution, and solubility of apple and carrot pomace

We investigated the effect of enzymatic treatment of apple and carrot pulp, as well as the method of drying the pomace obtained from the pulp, on the drying time of the pomace, the granulometric composition of the powders obtained from the pomace, and their solubility. Enzymatic treatment of apple pulp was carried out with the enzyme preparation Vegazym M (0.09% of the pulp weight) and carrot pulp – with Fructozym MA (0.07% of the pulp weight). Enzymatic treatment was carried out at a temperature of 50°C for 1 hour. Drying of pomace was carried out by the convective method in an ES-4620 drying cabinet at a temperature of 50°C and by the low temperature vacuum method in a laboratory vacuum unit by the Hetosicc company (Denmark) at a temperature of 35°C. As a result of the experiments, it was found that enzymatic treatment of the pulp increases the yield of apple juice by 26%, carrot juice – by 17%, while the amount of pomace obtained decreases. It was found that enzymatic treatment of the pulp reduces the drying time of the pomace: by 80 min with convective drying of carrot pomace, by 45 min with low temperature vacuum drying; with the convective method of drying apple pomace, the drying time of the pomace is reduced by 60 min, with the vacuum method – by 20 min. It was also found that enzymatic treatment of apple and carrot pomace increases the degree of destruction of the raw materials. Treatment of apple pomace with the enzyme preparation Vegazym M increased the number of particles passing through a 0.25 mm sieve by 2%, and treatment of carrot pomace with Fructozym MA – by 3.3% relative to the powders obtained from pomace without treating the pomace with enzyme preparations. Low temperature vacuum drying of pomace increases the number of particles passing through a Ø 0.25 mm sieve for apple pomace by 14% and for carrot pomace by 7.2%, compared to convective drying of pomace. In addition, vacuum drying of pomace increases the solubility of powders obtained from them by three times. The obtained results are recommended to take into account when developing a technology to obtain fruit and vegetable powders for enriching fermented beverages, both grain and juice based, fermented milk products to enhance the activity of the microorganisms, and for microbiological synthesis technologies.