In order to conserve perishable food and extend the permissible storage and marketing period, one of the best methods that uses artificial frost is freezing. The action of low temperatures leads to a slowing down of the modifying processes, both nutritionally and organoleptically. The researches presented within the paper aims to determine some specific parameters for the freezing process using an experimental model of a fast freezing equipment with liquid nitrogen. Experimental researches use two species of horticultural products, namely blueberries and green bean pods. The results indicate that the values of total freezing time, average linear freezing rate and liquid nitrogen consumption for quick freezing of blueberries were higher than those recorded for green bean pods. Also, with the lowering of the set temperature inside the freezing chamber, the freezing time from 0°C to the temperature of -15°C decreases, resulting in lower freezing times, higher average linear freezing rates and liquid nitrogen consumptions with increasing tendency.

Solar tray drying is an effective alternative for post-harvest processing of fruits and vegetables. Product quality and uniformity of the desired final moisture content are affected by the uneven air flow and temperature distribution inside the drying chamber. The purpose of this study is to numerically evaluate the operation parameters of a new indirect solar dryer having an appropriate design based on thermal uniformity inside the drying chamber, low construction costs and easy accessibility to resources needed for manufacture. The research was focused on both the investigation of different operation conditions and analysis of the influence of the damper position, which is incorporated into the chimney, on the internal cabinet temperature and air flow distribution. Numerical simulation was carried out with Comsol Multiphysics CFD commercial code using a reduced 2D domain model by neglecting any end effects from the side walls. The analysis of the coupled thermal-fluid model provided the velocity field, pressure distribution and temperature distribution in the solar collector and in the drying chamber when the damper was totally closed, half open and fully open and for different operation conditions. The predicted results were compared with measurements taken in-situ. With progressing computing power, it is conceivable that CFD will continue to provide explanations for more fluid flow, heat and mass transfer phenomena, leading to better equipment design and process control for the food industry.

Research refers to the ability to maintain the quality of dry onions in different conditions of temperature, the three varieties used in experimentation (De Buzau, Daytona and Countach) being stored after proper preparation at ambient temperature (+20…+22°C), refrigerated (+10…+12°C) and cold conditions (+3…+5°C). Storage life, the level of weight (mass) and decay losses and evolution of some chemical components determined from the 9 variants led to the conclusion that the best results were obtained by De Buzau variety for storage under ambient conditions and Daytona variety for storage under refrigerated and cold conditions. Moreover large differences between varieties and their behavior depending on storage conditions require choosing resistant cultivars and optimum storage temperatures according to destination and period of marketing or consumption.

Sensory attributes like colour, flavour and texture are makers in the consumer's purchasing decision of minimally processed organic apples. Drying using low temperatures represent a simple and easy way for minimally processing of organic fruits, moreover this procedure is accepted in organic agriculture. The aim of this study is to establish the consumer acceptance of organic apples dried using two different temperatures and how they characterize the final product. In order to accomplish the proposed purpose, three organic apples cultivars ‘Rubinola’, ‘Topaz’ and ‘Gemini’ were sliced and dried in a professional dryer with air distribution, using temperatures like 35°C and 50°C. Consumer general impression regarding obtained dried organic apples was based on a questionnaire, which contain several questions about colour, flavour, texture and size, in two sessions organized during two different scientific events. Dried organic apples were tasted and evaluated by consumers of both genders with ages between 22 and 66 years old. The slice size of organic dried apples was preferred by over 50% of consumers for all apple varieties. Consumers preferred more the taste of ‘Gemini’ cv. apples dried at 50°C compared to those dried at 35°C. The consumer’s acceptance of minimally processed organic apples was oriented towards those dried at 50°C. Obtained results suggest that sensory attributes are very important in consumer acceptance of a minimally processed product by drying technology and more studies are required.

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