Investigation of the influence of the processing method before drying on the organoleptic characteristics, the amount of weight loss and microbiological parameters of zucchini chips

Abstract

Drying is one of the most popular ways to preserve plant materials by reducing humidity and preventing microbiological contamination and it is a promising direction in the food industry. The article presents the results of the research in the development of effective technologies for preparing zucchini for drying, ensuring acceleration of the drying process, as well as maintaining or improving organoleptic characteristics (for example, to prevent excessive darkening). The article describes the results of the influence of pre-treatment of zucchini before drying on quality indicators – organoleptic indicators (appearance, consistency, taste, smell, color, shape, size) and physicochemical indicators (weight of fresh raw materials and dried product, moisture content of the finished product) and microbiological safety (MAFAnM, coliform bacteria, mold, yeast). The types of pre-treatment of zucchini before drying were microwave treatment, C6 H8 O7 solution (citric acid), NaCl solution (saline solution), microwave treatment + C6 H8 O7 solution, microwave treatment + NaCl solution. During the organoleptic assessment, it was found that the best organoleptic indicators are provided by treatment with 5% NaCl solution (4.8 points) and 1% C6 H8 O7 solution (4.7 points). Microwave pre-treatment in various parameters led to the appearance of characteristic bitterness and an unpleasant aftertaste. Treatment with a solution of citric acid in various dosages imparts a sour taste and prevented darkening during drying. It was found that various types of pre-treatment do not affect the duration of drying of zucchini, which was, on average, 7 hours. Microwave treatment reduced humidity to 3.4%, citric acid – to 3.6%, saline solution – to 4.6%, while complex treatment did not affect the reduction in moisture content of the dry product and, in general, the duration of drying. As a result of the microbiological assessment, it was noted that the amount of MaFAnM and mold fungi were within acceptable imits, and the growth of coliform bacteria was absent, which corresponded to the indicators of regulatory documents.