Harvesting and preserving tomatoes

Standard requirements for fresh tomatoes and tomatoes for processing vary. Although many varieties of tomatoes can both produce fresh fruit and serve as raw materials for processing. However, the requirements for each purpose are different, for example, fruits for processing must have beautiful colors, structure, content of dry matter, solute and sugar must be rotated according to standard of condensed tomato and soy sauce. tomato.

Consumers and processing experts all want and require tomatoes to be red. However, when transporting long distance, it is not possible to use red ripe fruits. So producers need to know and contract with traders who collect products to determine the right time to harvest fruits.

During ripening, tomatoes must go through the following periods:

- The period of green fruits: fruits and seeds are incomplete. If fruits are collected in this period and through the method of maturing, the ripe fruit is not normal, the fruit has no flavor, no characteristic color of the variety.

- Green ripening period: The surrounding glue is formed, the fruit is not pink or yellow. If ripened, the fruit will express the color of the variety.

- Golden ripening period: Fruit peaks appear yellow or pink with a surface area of ​​about 10%.

- The transition period: The surface area of ​​10-30% is yellow or red.

- Pink ripening period: The surface area of ​​fruit is 30-60% with light pink and yellow color.

- Period of persimmon or red fruit: Surface area of ​​fruits from> 60-90% is yellow or red.

- Period of red ripe fruit: Surface area from over 90% or more.

The above are important periods of ripening. From the time when ripe green to nine synthetic time is about 10-12 days. After that, the fruit ripens completely and has deep red color but the fruit is firm and hard. If used as food, it is most suitable and preferred by consumers. When soft fruit is still usable, but slicing will be difficult. Soft ripe fruits are suitable for seed collection, and the fruit pulp used to prepare tomato concentrate or tomato paste is very good.

When harvesting tomatoes by hand, due to collisions while arranging, transporting, crushed and bruised fruit, it is a good environment for increased infectious and respiratory diseases, causing spoilage and loss of quality. So the operation when collecting, arranging and transporting must be very gentle. Timely removal of crushed fruits etc . Currently in the tomato regions harvested by manual methods.

Temperature is a major influence on fruits after harvest.

Green tomatoes are very sensitive to cold below 10 degrees Celsius. The temperature in green ripe tomatoes must be reduced quickly from about 23 degrees Celsius to 21 degrees Celsius in 8-10 minutes or at 13-15 minutes to 15 degrees. degree C using cold water 1 -5 degrees Celsius.

Ripe tomatoes are less susceptible to cold, so they can be stored at 10-13 degrees Celsius for 4 days, then tomatoes can continue to ripen when the temperature rises. Light pink tomatoes can be stored at 5 degrees C for 4 days, then increase the temperature from 13-15 degrees Celsius from 1 to 4 days to complete the ripening period.

Red ripe fruits can be stored at a temperature of 2-5 degrees Celsius for some days. The following changes are discoloration, reduced stiffness and reduced flavor. Maintain air humidity during 85-90% storage to avoid wilting and wrinkling. To shorten the time during ripening, green tomatoes are exposed to ethylene (CH ₄ ) for 12-18 hours at a temperature of 20 degrees Celsius. Thus, it will reduce 1/2 time compared to average tomatoes. often. When necessary, it is possible to control the ripening process until the product is sold by adjusting the gas in the warehouse. Adjusting CO and O2 gas in warehouses is very difficult and complicated. The non-technician who regulates CO ₂ and O ₂ quickly reaches the critical level, if the balance can maintain the tomato, adjust the basic O ₂ level to a low level, while for the amount of CO also pay attention to adjust.

However, in most practical situations, tomatoes are stored at 5% CO2 and 2.5% O ₂ at 12 ^o c, when the basic CO ₂ ratio is 10% and O ₂ is 2.5 % of fungal pathogens will not grow in such an environment of high CO ₂ . To increase the effectiveness of disease control, adjust CO ratio: 2.5% and O: 2.5% as well.

Store in natural conditions. Choose fruits with medium fruit weight, when the fruit is solid. Select fruits in the green ripening period, collect fruits to arrange fruits in a cool place (not piled) to reduce the temperature in the fruit, reduce breathing. Use a soft cloth, clean fruit paper, remove the sepals, leave no cracks or tears. Then put the fruit on staging or put fruit into wooden trays, plastic trays, plastic trays can overlap but not too high. Fruit should be disposed when stored, regularly checked during storage to minimize loss of mass and quality.