Drying Characteristics and Microbiological Quality Assessment of Solar-Dried Tomato.

Tomato (Lycopersicon esculentum) is an important vegetable used in cooking most local foods in Ghana. At the peak season of harvesting, high loses are incurred because of the absence of tomato processing facilities to store, process, and extend the shelf life of fresh tomatoes. Solar drying has been proven to be a more efficient and low-cost method of enhancing quality and adding value to tomato and other vegetables. However, there are concerns about the functionality and quality of the dried products by consumers due to the methods of drying used. In this study, a passive mixed-mode solar dryer suitable for drying tomato was adapted and used to investigate the dehydration characteristics and microbiological quality of the dried tomato. The efficiency of a passive solar dryer was evaluated and used in the processing of fresh tomato to powder. The processing involved the pretreatment of 6 mm slices of fresh Roma variety of tomato by dipping in potassium metabisulfite solution and ascorbic acid solution. The moisture content, moisture ratio, and dehydration rate of solar-dried tomato were assessed. The 24 h dryer efficiency of 24.2% facilitated the drying process of tomato (final moisture content of 12-14%). Aerobic mesophile counts were lower in solar-dried tomato pretreated with potassium metabisulfite (3.90 CFU/g) compared with sun-dried samples (4.85 CFU/g). Solar-dried tomato powder is safer for consumption compared with open sun-dried tomato samples.

Sensory profiling and consumer evaluation of solar dried tomato powder in Ghana.

BACKGROUND: Tomato (Lycopersicon esculentum) is an important vegetable in Ghana, with high post-harvest losses due to absence of facilities to store, process and extend the shelf life of fresh tomatoes. Solar drying has been proven to be a more efficient and low-cost method of enhancing quality and adding value to tomato and other vegetables. However, there are concerns about sensory appeal of the dried products. In this study a natural mixed mode solar dryer was developed to dry pre-treated fresh Roma tomatoes. The sensory characteristics of the solar dried product was profiled and compared to the sensory properties of similar commercial dried tomato on the market using quantitative descriptive analysis methodology. Consumer testing using qualitative methods provided consumer feedback on the appeal of the solar dried tomatoes. RESULTS: Results showed that the solar dried tomato powder had a stronger tomato aroma intensity (scoring 127 on a 150 mm intensity scale) than the market products (0.7 on the same 150 mm intensity scale). When reconstituted, the solar dried tomato powder had a coarse appearance and texture, and a strong cooked tomato aroma compared to tomato paste. Consumers indicated that tomato powder was used as a thickener because it was highly viscous and when reconstituted imparted a desirable cooked tomato aroma and flavor. CONCLUSION: Considering the positions of the tomato products in the sensory space, although tomato powder had its own unique sensory properties, it also exhibited some sensory characteristics found in tomato paste. From this study, high-quality tomato powder has great potential for commercialization. © 2021 Society of Chemical Industry.

Consumer knowledge, preference, and perceived quality of dried tomato products in Ghana.

Postharvest losses (PHL) are incurred in the tomato value chain in Ghana and solar drying of tomato is a promising technology for reducing the loss. However, there are concerns on the usage, functionality and sensory appeal of the dried products to consumers, compounded with the lack of information and research on dried tomato processing in Ghana. A survey was carried out by administering semistructured questionnaires to 395 randomly selected and willing respondents in the Accra Metropolis. Information was obtained on the socioeconomic profile, consumption pattern, knowledge, and acceptance of tomato processing technologies and assessment of quality attributes important to consumers. Most consumers (74%) preferred tomato powder that is conveniently packaged to retain the characteristic intense taste and the flavor using Friedman's rank mean procedure. The study indicated that consumers were more concerned about good manufacturing practices during the production of solar-dried tomato (48.8%) rather than the quality attributes (8.6%). These findings indicate the need for safe solar drying procedures in order to increase consumer acceptability of solar-dried tomato products in Ghana.