阅读说明：本技术 一种延长保质期的蔓越莓干及其加工方法 (Dried cranberries with prolonged shelf life and processing method thereof ) 是由 汪英 张书光 刘卫光 齐路路 朱勇生 于 2019-11-15 设计创作，主要内容包括：本发明公开了一种延长保质期的蔓越莓干及其加工方法,属于食品加工领域。本申请以-10℃～-5℃缓冻的蔓越莓冻果为原料,经过刺孔、糖渍、烘干和拌油等工序制得,刺孔过程中控制温度不宜过高或过低,当温度低于零下10℃时,冰晶过于坚硬,造成不易刺孔,影响刺孔效率,当温度高于零下5℃时,会造成刺孔过程中,部分冻果解冻变软,产生破损过多,果形不饱满,因此,针对速冻的蔓越莓冻果而言,经过缓冻至-10℃～-5℃的蔓越莓冻果最为适宜刺孔,产品保留更多的自身带入的苯甲酸,进而保证其常温储存保质期2年以上。(The invention discloses a dried cranberry with a prolonged shelf life and a processing method thereof, and belongs to the field of food processing. The cranberry jelly is prepared by taking cranberry jelly slowly frozen at a temperature of between 10 ℃ below zero and 5 ℃ below zero as a raw material and performing the working procedures of punching, sugaring, drying, oil mixing and the like, wherein the control temperature in the punching process is not too high or too low, when the temperature is lower than 10 ℃ below zero, ice crystals are too hard, the holes are not easy to puncture, the punching efficiency is influenced, when the temperature is higher than 5 ℃ below zero, partial frozen cranberry is unfrozen and softened in the punching process, excessive damage is generated, and the fruit shape is not full, so that the cranberry jelly which is quickly frozen is most suitable for punching by slowly freezing the cranberry jelly at the temperature of between 10 ℃ below zero and 5 ℃ below zero, more benzoic acid brought by the cranberry jelly is reserved in the product, and the quality guarantee period of the cranberry jelly at normal temperature is more than 2 years.)

1. A processing method for prolonging the shelf life of dried cranberries is characterized in that the cranberries are prepared from frozen cranberries at a temperature of between 10 ℃ below zero and 5 ℃ below zero through the steps of punching, sugaring, drying, oil mixing and the like.

2. The processing method for prolonging the shelf life of the dried cranberries according to claim 1, wherein the dried cranberries are directly sugared after being punctured, the sugaring temperature is 25-35 ℃, the sugaring time is 3-8 days, and the sugar degree in sugared sugar liquor is 45-65%.

3. The processing method for prolonging the shelf life of the dried cranberries according to claim 2, wherein the drying temperature is 55-65 ℃, the drying time is 24-36 hours, the dried cranberries are mixed with 1-3 per mill of sunflower seed oil, and the content of the benzoic acid is kept between 0.1-0.3 g/kg.

4. The processing method for prolonging the shelf life of the dried cranberries according to claim 2, wherein the acidity of a sugar solution in the sugar soaking process is controlled to be 22-30%.

5. The processing method of claim 2, wherein the step of drying comprises drying the cranberry to a moisture content of about 12% to about 18%.

6. Dried cranberries produced by the method of any one of claims 1 to 5, which are storable at ambient temperature for more than 2 years.

Technical Field

The invention belongs to the field of food processing, and particularly relates to a dried cranberry with a prolonged shelf life and a processing method thereof.

Background

In recent years, fruit preserves are gradually enriched, the consumption of the preserves in the market of China is gradually increased, and the cranberry is more popular with consumers in China. Research shows that the cranberry has high content of nutrient components, is rich in bioactive substances such as flavonol, anthocyanin, ellagic acid, ursolic acid, cycloether terpene and resveratrol, and has good effects on preventing urinary tract infection, eliminating helicobacter pylori infection, resisting oxidation, resisting tumor and the like. The cranberry contains a certain amount of anthocyanin which is used as a natural pigment, the biological activity of the anthocyanin plays an important role in the health care of human bodies and the prevention and treatment of diseases, and the content of the anthocyanin in the cranberry is 13.6-140 mg/100 g. The cranberry also contains a certain amount of resveratrol which is an important polyphenol compound and has the characteristics of inflammation diminishing, cancer resistance and the like. The cranberries contain rich benzoic acid and have a natural preservative effect, but in the current market, the processing technology of dried cranberries adopts sugar soaking after juice extraction, so that the content loss of benzoic acid, anthocyanin and the like of the cranberries is high, the quality guarantee period is shortened, and the nutrient loss is high. Therefore, how to process the cranberry without juice extraction and sugar immersion, but the cranberry has the quality of processing the cranberry after juice extraction, is a problem to be solved urgently at present.

Through retrieval, the Chinese patent application publication number: CN106333044A, publication date: 2017.1.18A method for processing dried cranberry comprises cleaning fresh cranberry after color protection, pickling with salt for 3-7 days, adding white sugar, Mel, radix Glycyrrhizae powder, cortex Cinnamomi powder, and sodium benzoate, sugaring, drying, and sterilizing. The licorice powder and the cinnamon powder added into the cranberry can dissipate exterior cold, tonify middle-jiao and replenish qi, and neutralize the cold property of the cranberry; the fresh taste of the cranberry is increased by the combined action of the licorice powder and the honey. However, during the salting process of the fresh cranberries, the content loss of benzoic acid, anthocyanin and the like of the cranberries is increased inevitably, and the quality guarantee period is shortened.

Disclosure of Invention

1. Problems to be solved

Aiming at the problem that the shelf life is easily shortened in the existing cranberry processing process, the invention provides a dried cranberry with a prolonged shelf life and a processing method thereof. The cranberry jelly is prepared from cranberry jelly slowly frozen at a temperature of between 10 ℃ below zero and 5 ℃ below zero, and is most suitable for pricking holes, and the product can retain more benzoic acid brought by the cranberry jelly, so that the quality guarantee period of the product is prolonged.

2. Technical scheme

In order to solve the above problems, the present invention adopts the following technical solutions.

A processing method for prolonging the shelf life of dry cranberries comprises the following steps of taking cranberry frozen fruits slowly frozen at a temperature of between 10 ℃ below zero and 5 ℃ below zero as a raw material, and carrying out the working procedures of punching, sugaring, drying, oil mixing and the like, wherein the temperature is not controlled to be too high or too low in the punching process, when the temperature is lower than 10 ℃ below zero, ice crystals are too hard, so that the punching efficiency is not easily punctured, and when the temperature is higher than 5 ℃ below zero, part of the frozen cranberries are thawed and softened to generate excessive damage and are not full, so that the quick-frozen cranberry frozen fruits are most suitable for punching, the product retains more benzoic acid brought by the product, and the corrosion prevention mechanism of the benzoic acid is as follows: the undissociated benzoic acid has strong lipophilicity and can easily pass through a cell membrane to enter cells, interfere the permeability of microbial cell membranes such as molds and bacteria, prevent the absorption of amino acid by the cell membrane, enter the benzoic acid molecules in the cells, acidify alkali in the cells, and inhibit the activity of a respiratory enzyme system in the microbial cells, so that the preservative effect is achieved, the quality guarantee period is prolonged, and other beneficial nutritional ingredients such as resveratrol and flavonol of the cranberry are kept as far as possible.

Further, after punching, directly sugaring, wherein the sugaring temperature is 25-35 ℃, the sugaring time is 3-8 d, the sugar degree in sugared sugar liquor is 45-65%, in the sugaring process, the sugar degree is not too high or too low and is less than 45, the sugaring is slow, the product is peracid, when the sugar degree is more than 65, the sugar conversion is insufficient, the product is sand-turned, the taste is excessively sweet, the proper temperature range and the sugaring time are combined, and the adaptive sugar degree range is combined, so that the prepared cranberry dried bean curd has a good taste suitable for common people while the quality guarantee period is prolonged; and after the cranberry jelly is heated and melted, the spiny cranberry jelly is added into the sugar solution for soaking, and the acidic substances in the cranberry juice are utilized to promote the conversion of the sugar.

Furthermore, the drying temperature is 55-65 ℃, the drying time is 24-36 hours, the sunflower seed oil is mixed for 1-3 per mill after drying, the medium-temperature long-time drying is carried out, the maximum maintenance of the nutrient components of the materials is guaranteed, the sunflower seed oil is mixed after drying, the reasonable oil mixing proportion is realized, the adhesion is avoided, and meanwhile, the rich taste and the nutrient components of the product are improved.

The further processing method comprises the steps of ensuring that microorganisms are not bred by utilizing high osmotic pressure in the sugar curing treatment, controlling the acidity of sugar liquor to be 22-30%, controlling the balance of sugar and acid by controlling the sugar curing time and the sugar degree of sugar curing liquid, always balancing the sugar and the acid by the acid of the cranberry and the sugar curing liquid in the sugar curing process, keeping the content of benzoic acid to the maximum extent, ensuring that the content of the benzoic acid is 0.1-0.3 g/kg, and further ensuring the quality guarantee period of products.

In the further processing method, the cranberry is dried in the drying procedure until the moisture content is about 12-18%, and the moisture content range is matched with the range of 0.1-0.3 g/kg of benzoic acid content, so that the shelf life of the prepared cranberry dried food can be guaranteed to be more than 2 years at normal temperature.

A dried cranberry obtained by the above method can be stored at room temperature for more than 2 years.

3. Advantageous effects

Compared with the prior art, the invention has the beneficial effects that:

(1) the processing method for prolonging the shelf life of the dried cranberries is characterized in that the frozen cranberries which are slowly frozen at the temperature of-10 ℃ to-5 ℃ are used as raw materials, and the processing method is prepared by the working procedures of punching, sugaring, drying, oil mixing and the like, the control temperature in the punching process is not too high or too low, when the temperature is lower than minus 10 ℃, ice crystals are too hard, the punching efficiency is not easy to be punched, and when the temperature is higher than minus 5 ℃, part of the frozen cranberries are thawed and softened, the damaged parts are too much, and the shapes of the fruits are not full, so that the frozen cranberries which are slowly frozen to the temperature of-10 ℃ to-5 ℃ are most suitable for punching, the product retains more benzoic acid brought by the product, and the corrosion prevention mechanism of the benzoic acid is as follows: the undissociated molecules act, undissociated benzoic acid has strong lipophilicity and can easily pass through a cell membrane to enter cells, interfere the permeability of microbial cell membranes such as molds and bacteria and the like, prevent the absorption of amino acid by the cell membrane, enter the benzoic acid molecules in the cells, acidify alkali stored in the cells, and inhibit the activity of a respiratory enzyme system in the microbial cells, so that the preservative effect is achieved, the quality guarantee period is prolonged, other beneficial nutritional ingredients such as flavonol, anthocyanin, ellagic acid, ursolic acid, cycloethylen terpene and resveratrol and bioactive substances of the cranberry are kept as far as possible, and the preservative effect plays an important role in the health care and the disease prevention and treatment of human bodies;

(2) according to the processing method for prolonging the shelf life of the dried cranberries, in the sugar soaking process, the sugar degree is not too high or too low, and is lower than 45, the sugar soaking is slow, the product is too acid, when the sugar degree is higher than 65, the sugar conversion is insufficient, the product is sand-turned, the taste is too sweet, the proper temperature range and the sugar soaking time are combined, and the prepared dried cranberries have good mouthfeel suitable for common people while the shelf life is prolonged; and after the cranberry is heated and melted, the spiny cranberry jelly is added into the sugar solution for soaking, and the acidic substances in the cranberry juice are utilized to promote the conversion of the sugar;

(3) according to the processing method for prolonging the shelf life of the dried cranberries, the dried cranberries are dried at medium temperature for a long time, so that the maximum maintenance of the nutritional ingredients of the materials is guaranteed, the sunflower seed oil is stirred after the dried cranberries are dried, the oil stirring ratio is reasonable, the rich taste and the nutritional ingredients of the product are improved while the adhesion is avoided, and the product is bright and is not dirty;

(4) the processing method for prolonging the shelf life of the dried cranberries controls the balance of sugar and acid by controlling proper sugar soaking time and sugar degree of sugar soaking liquid, the sugar and acid are always balanced by the acid of the cranberries and the sugar soaking liquid in the sugar soaking process, so that the content of benzoic acid is kept to the maximum extent, and the content of 0.3-1.3 g/kg of benzoic acid in a fresh raw material is used for reducing loss in the whole processing process to the maximum extent so as to ensure that the content of the benzoic acid is between 0.1 and 0.3g/kg, so that the shelf life of a product is ensured;

(5) according to the processing method for prolonging the shelf life of the dried cranberries, the dried cranberries are dried in the drying process until the moisture content is about 12-18%, and the moisture content range is matched with the range of 0.1-0.3 g/k of benzoic acid content, so that the shelf life of the prepared dried cranberries can be stored at normal temperature for more than 2 years.

Detailed Description

The invention is further described with reference to specific examples.