阅读说明：本技术 一种柿饼及其冷链处理方法 (Dried persimmon and cold chain treatment method thereof ) 是由 高小平 于 2018-08-20 设计创作，主要内容包括：本发明将公开一种柿饼,本发明还将公开这种柿饼的冷链处理方法,其步骤如下：1)柿饼的加工：将柿子加工成含水量为28～43％的柿饼；2)速冻：将加工好的柿饼置于-30～-35℃、风速为3～5m/s环境中速冻；3)贮藏：将速冻后的柿饼转移至-12～-22℃温度条件下贮藏；4)运输：柿饼在-18～-15℃环境中运输；5)销售：柿饼在销售过程中保持-12～-22℃的温度条件。经本发明冷链处理方法处理的柿饼,含水量保持在28～43％,外形美观,表面无霜或有轻微均匀的柿霜,质地柔软、果肉细腻爽口、口感独特、返涩率极低,在-18～-22℃、85～95％湿度的冷藏条件下,这种高含水量的柿饼仍有一年以上的保质期。(The invention discloses dried persimmon and a cold chain treatment method of the dried persimmon, which comprises the following steps: 1) processing of dried persimmon: processing the persimmons into dried persimmons with the water content of 28-43%; 2) quick-freezing: quickly freezing the processed dried persimmons in an environment with the temperature of minus 30 to minus 35 ℃ and the air speed of 3 to 5 m/s; 3) and (3) storage: transferring the quick-frozen dried persimmons to the temperature of between 12 ℃ below zero and 22 ℃ below zero for storage; 4) and (3) transportation: transporting the dried persimmon in an environment of-18 to-15 ℃; 5) and (3) selling: the temperature condition of the dried persimmon is kept between-12 ℃ and-22 ℃ in the sale process. The dried persimmon processed by the cold chain processing method has the advantages of water content of 28-43%, attractive appearance, no frost or slight uniform frost on the surface, soft texture, fine and refreshing pulp, unique taste and extremely low astringency return rate, and the dried persimmon with high water content still has the quality guarantee period of more than one year under the refrigeration condition of-18 to-22 ℃ and 85-95% humidity.)

1. The cold chain processing method of dried persimmons comprises the following steps:

1) processing of dried persimmon: processing the persimmons into dried persimmons with the water content of 28-43%;

2) quick-freezing: quickly freezing the processed dried persimmons in an environment with the temperature of minus 30 to minus 35 ℃ and the air speed of 3 to 5 m/s;

3) and (3) storage: transferring the quick-frozen dried persimmons to the temperature of between 12 ℃ below zero and 22 ℃ below zero for storage;

4) and (3) transportation: transporting the dried persimmon in an environment of-18 to-15 ℃;

5) and (3) selling: the temperature condition of the dried persimmon is kept between-12 ℃ and-22 ℃ in the sale process.

2. The cold-chain processing method of dried persimmons according to claim 1, wherein: and 3), transferring the quick-frozen dried persimmons to the temperature of between 18 ℃ below zero and 22 ℃ below zero for storage.

3. The cold-chain processing method of dried persimmons according to claim 1 or 2, characterized in that: in the step 5), the temperature condition of minus 18 to minus 22 ℃ is kept during the sale process of the dried persimmon.

4. The cold-chain processing method of dried persimmons according to claim 1 or 2, characterized in that: in the step 1), 7-8 min of mature fresh persimmons are selected and washed, and then deastringency treatment and dehydration treatment are carried out to obtain the dried persimmons.

5. The cold-chain processing method of dried persimmons according to claim 1 or 2, characterized in that: in the step 1), the deastringency treatment is carbon dioxide deastringency, or lime water deastringency, or natural deastringency.

6. The cold-chain processing method of dried persimmons according to claim 1 or 2, characterized in that: in the step 1), the dehydration treatment is drying or airing.

7. The cold-chain processing method of dried persimmons according to claim 1 or 2, characterized in that: in the step 3), the storage humidity of the dried persimmons is 85-90%.

8. Dried persimmons obtained by the cold chain treatment method according to any one of claims 1 to 7.

Technical Field

The invention relates to a food, in particular to dried persimmon, and also relates to a cold chain treatment method of the dried persimmon.

Background

The persimmon is a special product in China, the yield accounts for 70-80% of the world, and except China, the persimmon is only planted in a few countries such as Japan and Korea. Persimmon is a high-quality and rich-nutrition fruit and is deeply loved by people, but the sale and development of the persimmon are restricted due to the characteristics of easy softening, easy decay, difficult storage and long-distance transportation, short eating period and the like of the persimmon. In order to solve this problem, many production sites carry out deep processing of persimmons, for example, as described in application nos.: 200510096238.x, entitled "method for preparing lyophilized micropowder of fructus kaki", is a method for processing fresh fructus kaki by vacuum freeze drying dehydration, which comprises: selecting ripe persimmons of seventy-eight parts, removing astringent taste with warm water, cutting the persimmons into small pieces, placing the small pieces into a drying chamber of a vacuum freeze dryer for quick freezing, vacuumizing and heating the persimmon pieces after the persimmon pieces are completely frozen to sublimate ice crystals in the persimmon pieces, and after the freeze-drying process is finished, carrying out coarse grinding and superfine grinding on the persimmon pieces by adopting a grinder so as to obtain the persimmon freeze-dried superfine powder. The obtained fructus kaki micropowder retains inherent fragrance and nutritional components of fructus kaki, has good solubility, and can be used as raw material for preparing beverage, fruit crystal, and soft candy, or as additive for fruit food. In addition, there are also companies or home workshops that process persimmons into dried persimmons to prolong the shelf life of the fruits. At present, the water content of the dried persimmons sold on the market is about 21-28%, the dried persimmons are black brown, and white dried persimmons are attached to the whole surface of the dried persimmons. Because the moisture content of the dried persimmon is low, the dried persimmon can be stored for several months at normal temperature without refrigeration; however, the persimmon cake has hard pulp and rough taste, and with the improvement of the requirements of modern consumers on diet and health, white persimmon frost attached to the surface of the persimmon cake is easily considered as a dirty substance, and people like to wash out the nutrient-rich persimmon frost before eating the persimmon cake, and then the persimmon cake can be eaten safely after being soaked in hot water or steamed and softened by a pot, so that tannin in the persimmon is reduced after being subjected to high temperature, and the originally deastringent persimmon cake loses the taste and even is difficult to eat.

Disclosure of Invention

The invention provides dried persimmon which has high water content, soft texture, beautiful appearance, basically no persimmon frost and unique taste; in order to keep the taste and color of the dried persimmon, the invention also discloses a cold chain treatment method of the dried persimmon.

The invention relates to a cold chain treatment method of dried persimmons, which comprises the following steps:

1) processing of dried persimmon: processing the persimmons into dried persimmons with the water content of 28-43%;

selecting 7-8-minute ripe fresh persimmons without diseases, insect pests, rot and scars, washing the persimmons, and performing astringency removal treatment; because fresh persimmons contain a large amount of tannin, strong astringency is generated during eating, and astringent taste is generated; in order to make the finished dried persimmon product have no astringent taste, deastringency treatment is carried out in the processing process, but the persimmon is not beneficial to deastringency after being processed into dried persimmon, so the deastringency treatment is generally selected when the persimmon is still in a fresh state; the deastringency treatment can be conventional deastringency treatment methods such as carbon dioxide deastringency, lime water deastringency, natural deastringency and the like, and generally, natural deastringency is adopted; in order to achieve a better astringency removal effect and reduce the time consumed by astringency removal, carbon dioxide or lime water can be used for astringency removal; then, carrying out dehydration treatment on the persimmons subjected to astringency removal, wherein the dehydration treatment can be carried out by adopting a drying method or an airing method, the common method is the airing method, the drying is to peel the persimmons subjected to astringency removal, place the persimmons in an environment with the temperature of 40-58 ℃, take out the persimmons after being dried for 10-12 hours, manually knead the persimmons, place the persimmons in the environment for 10-12 hours after being parked for 12 hours, and repeat the operation for 3-4 times; when natural deastringency is adopted for deastringency treatment and airing is adopted for dehydration treatment, the deastringency treatment and the dehydration treatment can be combined into a whole, namely, the persimmons are peeled and then placed in a persimmon cake sieve for airing day, the airing time can be determined according to the weather and the temperature, and the airing time is more suitable for 7-12 days when the persimmon cake is aired at 19-32 ℃ in 10-11 months according to the mature time of the persimmons and in order to well control the water content of the persimmon cake within the range of 28-43%; in order to accelerate the metabolism of the persimmons to decompose the glue layer in the cell walls of the persimmons and convert the tannin substances into water-insoluble substances so as to achieve a better astringency removal effect, the persimmons are preferably manually kneaded during the airing period, and generally, the effect achieved by kneading 3-6 times during the airing period is better; the persimmon is dried at the bottom of 11-12 months at the temperature of 10-23 ℃, the drying time is 15-25 days, and the persimmon can be kneaded every 1-2 days during the drying process to achieve a good astringency removal effect; the persimmon is processed into dried persimmon, and the dried persimmon can be sterilized in order to meet the corresponding food sanitation requirement and preservation purpose, and the commonly adopted method is a sulfuring method; in order to prevent the astringent taste of the dried persimmon caused by the sterilization treatment, the sulfur consumption, the sterilization time and the sterilization frequency need to be strictly controlled, generally speaking, the sulfur is smoked for 5-10 minutes at the sulfur consumption of 20-50 g/m3, the sterilization frequency is 1-2 times, and the obtained effect is good, and other sterilization methods can be adopted to sterilize the dried persimmon; in order to facilitate transportation and sale, the sterilized dried persimmons are preferably packaged in different ways, and the specification of the packaging can be determined according to specific requirements;

2) quick-freezing: quickly freezing the processed dried persimmons in an environment with the temperature of minus 30 to minus 35 ℃ and the air speed of 3 to 5 m/s;

the dried persimmon is easy to deteriorate when being stored at normal temperature due to high water content, even has astringent taste, loses the original taste, and cannot be eaten, and the cold chain treatment is carried out on the dried persimmon in order to stabilize the original color, water content and nutrient substances in the dried persimmon and keep the original fine taste of the dried persimmon; the dried persimmon is quickly frozen in an environment with the temperature of minus 30 to minus 35 ℃ and the wind speed of 3 to 5m/s, the dried persimmon passes through ice crystals with the temperature of minus 1 to minus 5 ℃ within 30 minutes to form a belt, and the dried persimmon is transferred to a storage warehouse for storage when the central temperature of the dried persimmon is less than or equal to minus 18 ℃;

3) and (3) storage: transferring the quick-frozen dried persimmons to the temperature of between 12 ℃ below zero and 22 ℃ below zero for storage;

the storage temperature of the dried persimmon can be determined according to the storage time of the dried persimmon, the storage temperature is not too high or too low, the storage temperature is too high, the quality guarantee time is extremely short, and the dried persimmon is easy to produce frost or mildew; the phenomenon of astringent taste of the dried persimmon is caused by too low temperature, the color of the dried persimmon is changed to yellow, the pulp is frozen into blocks, the dried persimmon is inconvenient to eat, and the taste is also poor; the following comparative experiments are carried out by the applicant at six storage temperatures of 20-25 ℃, 1-5 ℃, 3-8 ℃, 12-14 ℃, 18-22 ℃ and 26-30 ℃ for 30 days and 90 days respectively, and the experiments analyze the number, color, odor, taste and moisture content change, the existence of astringency and the frosting state of samples, and are shown in table 1 and table 2:

TABLE 1 sensory analysis of dried persimmon at different refrigeration temperatures (30 days)

TABLE 2 sensory analysis of dried persimmon at different refrigeration temperatures (90 days)

The above experimental data show that: the dried persimmon is preserved and stored for a short time, for example, when the preservation time is 1-4 weeks, the storage temperature can be-3-5 ℃, and the dried persimmon does not produce persimmon frost or go bad; after the persimmon cake is preserved and stored for 90 days, the quality of the persimmons stored at the temperature higher than minus 8 ℃ is gradually reduced along with the prolonging of time, and the persimmons are shown as darkening and blackening of color and luster, aggravation of peculiar smell, persimmon frost, mildew or other deterioration phenomena can be respectively caused, in order to prevent darkening and blackening of color and luster of the persimmon cake, peculiar smell, persimmon frost, mildew and other deterioration phenomena, the persimmon cake can be stored in the temperature environment of minus 12 to minus 22 ℃, and the storage is preferably carried out at the temperature of minus 18 to minus 22 ℃; in order to maintain the moisture in the dried persimmon and to ensure the taste of the dried persimmon, the humidity of the dried persimmon during storage is also required, and the following experimental results are obtained by the inventors comparing the appearance and taste of the dried persimmon stored at-18 ℃ for 90 days in four humidity environments of 80%, 85%, 90% and 95%, and are shown in table 3:

TABLE 3 Table of storage conditions of dried persimmon in different humidity environments

Therefore, the storage humidity is preferably controlled to be 85-90%;

4) and (3) transportation: transporting the dried persimmon in an environment of-18 to-15 ℃;

because the transportation needs a long time, the transportation at low temperature is preferably adopted in order to keep the quality and the taste of the dried persimmons, and the transportation is generally suitable in the environment of-18 to-15 ℃; before the dried persimmon is delivered out of the warehouse, the temperature of the dried persimmon can be cooled by freezing, so that the temperature of the dried persimmon reaches-22 ℃, and the time for getting on or off the product is controlled within 2.5 hours.

5) And (3) selling: the temperature condition of the dried persimmon is kept between-12 ℃ and-22 ℃ in the sale process.

The dried persimmon can keep better appearance and color under low temperature conditions, especially under the temperature condition of-12 to-22 ℃, more preferably under the temperature condition of-18 to-22 ℃, the effects of the appearance, color and taste of the dried persimmon are very good, the advantages of the dried persimmon are fully displayed to consumers, and more consumers can be won under the premise of comparing with the original dried persimmon.

The invention also comprises the dried persimmon processed by the cold chain processing method.

The dried persimmon processed by the cold chain processing method has the water content of 28-43 percent, attractive appearance, no frost or slight even persimmon frost on the surface, soft texture, fine and refreshing pulp and unique taste, and is a green food; the problems that the persimmons are easy to mildew and difficult to store and transport and the like are solved while the nutritional ingredients in the fresh persimmons are fully maintained; under the refrigeration condition of-18 to-22 ℃ and 85 to 95 percent of humidity, the dried persimmon with high water content still has more than one year of shelf life, and has extremely low astringency return rate, no discoloration, no hardening, no soft rot, no frostbite and no obvious change in sugar degree and taste after being thawed.

Detailed Description