Yellowing techniques with the corresponding fruit-waxing are used in order to ensure the preservation of the fruit and the improvement of its appearance. It is known that the degreening parameters are dependent on climatic conditions. The use of the continuous venting method renders the operation of the degreening chamber more economical and more readily automated. In this respect, ethylene manometer dosers permit wide-range dosage of gas, in addition to allowing for flow adjustment by means of valves.

Summary:

Yellowing techniques with the corresponding fruit-waxing are widely used in order to ensure the conservation of citrus fruit and the improvement of their appearance.

Request:

We would like to know the latest methods developed for yellowing of citrus fruits, as well as the latest improvements.

SEARCH REPORT

a. Field of Search (IPC): A 23 B 7/00; A 23 L

b. Pertinent literature:

Patent documents

2,062,903

2,072,022

2,425,073

2,503,664

2,503,665

2,507,438

2,582,868

10.

11.

12.

13.

14.

3,458,627

1,475,938

1,846,143

1,920,540

2,577,421

3,034,903

3,522,057

Non-Patent Literature

15. Chemical Abstracts 1970, Vol. 72, 120152j

16. Chemical Abstracts 1972, Vol. 76, 111807g

17. Chemical Abstracts 1973, Vol. 79, 39264v

18. Chemical Abstracts 1973, Vol. 79, 90616p

19. Chemical Abstracts 1974, Vol. 81, 36659h

c. Comments:

Patent documents (1) to (8) relate to coloring citrus fruit by means of dyes.

According to patent document (1) an oil-soluble, water-insoluble, dye is used. Patent document (2) describes a process which involves mixing a coloring matter soluble in the natural wax present in the peel of the fruit with a dry, solid carrier, and applying the mixture to the surface of the fruit.

Patent document (3) relates to a process for treating whole fruit and vegetables, which involves forming an aqueous dispersion of a way containing an oil-soluble dye and applying that dispersion to whole fruit.

According to the processes described in patent documents (4) and (5), the dye is suspended in the solution of a salt of an amine, the amine having at least one hydrocarbon chain of at least 10 to 20 carbon atoms.

According to patent document (6), the fruit is flooded with an aqueous emulsion of edible dye.

Patent document (7) deals with a non-aqueous concentrate and a process of coloring citrus fruit with the said concentrate.

In patent document (8), a composition for preserving gathered fruit and vegetables is described which also improves the color of the treated matter.

Patent documents (9) to (14) deal with coloring citrus fruit by means of coloring gases.

In patent document (9) and (11) ethylene gas is used.

Patent document (10) relates to a process for coloring citrus fruit which involves spreading a thin coating of protective material over the surface of the fruit and subjecting the coated fruit to the action of a coloring gas.

Patent document (12) describes degreening by treatment with an atmosphere containing a member of the group consisting of ethylene oxide, trichlorethane and ethylene dichloride.

According to patent document (13), fresh oranges are subjected to the action of the vapors from a liquid mixture consisting of substantially equal portions of 1,1,1,trichlorethane and methylenechloride.

Patent document (14) deals with a process for degreening and ripening fruit by treating stored fruit with a circulating airstream maintained at a selected fruit processing temperature.

The abstracts found in 'Chemical Abstracts' describe the following:

(15) modified atmosphere for ripening fruit and vegetables in chambers.

(16) Carotenoids in citrus fruit.

(17) Process for post-harvest-ripening and degreening of bananas and citrus fruit.

(18) Optimum temperature and ethylene concentrations for post-harvest development of carotenoid pigments in citrus.

(19) The influence of refrigeration on the commercialization of citrus fruit.

Amended Reasons

Amended Reason	Date Amended
	18 Oct 2023
Publishing for testing	06 Jun 2023