UUDISED

GOOD PROJECT EXAMPLE: Microbiological Control of Vegetables, Optimization of Storage Conditions and Development of New Product Groups to Decrease Post-harvest Losses

The problem to be solved

Estonian summers have become warmer and longer resulting in higher yields of some crops. However, farmers should store their harvest correctly to be able to provide consumers with fresh vegetables also in winter months. Preservation of vegetables depends on several factors, such as the microflora of the product, cleanliness of storages, temperature, humidity, concentration of CO2 in the air and lots of other factors.

A project on the research on the perishability of vegetables was initiated in cooperation with Sagro Food Ltd. and the Center of Food and Fermentation Technologies Ltd. The objective of the project was to determine whether the microflora of vegetable storages had an impact on the preservation of the vegetables stored in these rooms and optimize the preservation conditions in the storages if need be. Secondly, the project aimed at contributing to the development of new vegetable products from non-standard vegetables not suitable for storing and from secondary raw material by usinginnovative food production technologies. 

“Non-standard vegetables should not be disposed of any longer because they can be easily used for the production of different products such as vegetable chips, purees and shredded products.” Ingrid Sumeri, the project leader of the Center of Food and Fermentation Technologies

Project outcomes

The outcome of the project was, that mostly harmless soil microorganisms, also bacteria and fungi which belong to the rhizosphere and phyllosphere of plants, dominated in the vegetables subject to research. Monitoring of the physical parameters such as temperature, air humidity and the concentration of CO2 in the air of the storage rooms has revealed that air humidity should be lower (up to 85%) in storages with higher temperatures (+4...+6°C) to avoid the thriving of grey mould. To conclude, it can be said that 16S genetic sequencing helps to analyse the microbiological composition of soil, vegetables, as well as vegetable storages. The results reveal whether vegetables are contaminated with pathogens or whether just commensal bacteria and fungi are living on them. Such kind of research helps farmers to clean their storages more efficiently and store their vegetables correctly in the future. The monitoring of physical parameters in vegetable storages contributes to ensuring longer storage life of products.

In the course of the project, innovative technologies were developed for the production of different products: freeze-dried and instant controlled pressure drop dried beetroot powder, raw and boiled beetroot spirals (in vacuum packages and modified environment), cabbage rice (fresh shredded cabbage in vacuum package), traditional oven-fried, as well as lyophilized vegetable chips and fresh beetroot puree. Most of these products can be easily produced and do not require big investments for purchasing the equipment.