CN101946613B - Sweet potato for processing preserved sweet potato and cultivation method and application thereof - Google Patents

Abstract

The invention discloses a sweet potato for processing preserved sweet potato and a cultivation method and an application thereof, belonging to the field of cultivation and processing of the sweet potatoes. The No.18 Ji sweet potatoes cultivated by adopting the cultivation method can be processed into the high-quality low-sugar purple preserved sweet potato without any additives by cleaning, shaping, steam-boiling, saccharification and baking. The preserved sweet potato has the characteristics of soft texture, low sugar content and translucent color and luster, is rich in anthocyanin and selenium element, has oxidation resistance and high free radical removing capacity which is 20 times of VE and 50 times of VC, and can prevent cardiovascular diseases, prevent tumors, prevent mutation, prevent radiation, delay aging, improve immunity and have good anti-cancer effect.

Description

A kind of sweet potato and cultivation method and application that is used for preserved sweet potatoes processing

Technical field

The present invention relates to Rhizoma Dioscoreae esculentae No. 18 sweet potato and cultivation method thereof, processing method, belong to sweet potato cultivation and manufacture field.

Technical background

Rhizoma Dioscoreae esculentae No. 18 is that the crop investigations of academy of agricultural sciences, Shandong Province is cooperated with the International Potato Center, do maternal with Xu's potato 18, let alone pollination (male parent colony is 38 external kinds) and obtain true seed, through the approval test of primary election garden, final election garden and multiple years, bred high yield, high-quality, disease-resistant purple sweep potato new varieties in 2002.It is special with the examination of type variety plot that 2002-2003 has participated in national sweet potato variety regional test, and the attributional analysis result is: the cyanine plain color valency of Ji potato 18 is 15.55, and colour is 1.54, and content is 16.23mg/100g.The testing result of Ministry of Agriculture food quality supervision verification test center (Jinan) is: the moisture of Ji potato 18 is 77.4% (method is according to GB/T5009.3-2003); Soluble sugar content is 8.82% (method is according to GB/T6194-1986); The selenium constituent content is 4.88 * 10-3ug/g (method is according to GB/T5009.93-2003).Ji potato 18 colors of the leather are purple black, and are yellowish pink purple, the long spindle of potato shape, and the potato skin is smooth, and commodity is good, and commodity rate is up to more than 90%, and the meat exquisiteness is the splendid sweet potato variety for health care of eating raw, is particularly suitable for preserved sweet potatoes processing.

The preserved sweet potatoes processing technology originates from the rural area at first, and baking potato dried meat is a traditional product in rural area, and common process adopts and cleans the back boiling, through shaping, is placed on draughty local natural air drying.Early 1990s, many local workshops and enterprise begin the manufacture craft of this traditional product is carried out upgrading, and carry out the further investigation of processing specific breed seed selection and processing technology.Improved technology with sweet potato boiling after cleaning, peeling, shaping, is handled through saccharification again, is placed on then with drying 24h in the high hot house of quirk heating naturally.Improved technology has been avoided the pollution of dust in the outdoor air drying process; be not subjected to the restriction of weather yet; but still there are many drawbacks in the product that processes; show mainly that sugariness is big, poor toughness, poor, the about hardness of glutinous property be irregular; healthy nutritive value is general, and must add preservative in order to make product have long protection period.

The purple sweep potato dried meat is a potato dried meat new product of market fast sale after 2005, because it is rich in anthocyan and selenium element, healthy nutritive value is significantly higher than the sweet potato of other potato yellowish pinks, thereby to become market new lover, price rapidly be the several times of red heart potato dried meat.But because purple potato meat Sweet Potato Breeding starts late in China, the purple potato kind that is fit to processing potato dried meat lacks very much, and the kind that is suitable for processing the potato dried meat requires dry matter and moisture moderate, the soluble sugar content height, and viscosity is good, adopts easily saccharification of back, and fiber content is few.The Rhizoma Dioscoreae esculentae No. 18 sweet potato be generally acknowledge up to now be suitable for one of purple sweep potato kind few in number of processing preserved sweet potatoes most, if but cultivation method is improper, commodity potato after the results is through conventional method processing preserved sweet potatoes, not only still there are poor toughness, poor, the about hardness of glutinous property is irregular, color and luster is uneven defective, and with the nutritive value of heavy losses Rhizoma Dioscoreae esculentae No. 18 sweet potato.Relevant test shows, utilizes produced in conventional processes purple sweep potato dried meat, and it is about 30% that nutritive value loses, and causes the actual eating effect of purple sweep potato not good thus.

Summary of the invention

For overcoming above the deficiencies in the prior art, give full play to the kind commodity production advantage of Rhizoma Dioscoreae esculentae No. 18 sweet potato, the invention provides a kind of sweet potato and cultivation method thereof that is used for preserved sweet potatoes processing, the present invention also provides the method with this sweet potato processing purple sweep potato dried meat.

Technical scheme of the present invention is as follows:

A kind of sweet potato that is used for preserved sweet potatoes processing is characterized in that obtaining by following cultivation method:

(1) select Rhizoma Dioscoreae esculentae No. 18 potato seed piece to carry out the seedbed and cultivate, spray around potato seed pieces and the seedbed 1 meter with interior zone with 800 times of dilutions of carbendazim, every mu of consumption 1300-1400 rises dilute solution, disposable spraying when growing seedlings; The seedbed is cultivated and was got Rhizoma Dioscoreae esculentae No. 18 sweet potato seedling in 30-40 days;

(2) select the anosis sandy loam plot of the sweet potato of not planting more than 2 years for use, at the beginning of 6 months of the annual Gregorian calendar, the Rhizoma Dioscoreae esculentae No. 18 sweet potato transplantation of seedlings that step (1) is cultivated is to the land for growing field crops, and planting density is 4000-4500 strain/mu.

(3) every mu of fertilising is as follows before the whole ground ridging: biological organic fertilizer 280-300 jin, nitrogen-phosphorus-potassium compound fertilizer 55-60 jin, wherein nitrogen: phosphorus: potassium=15: 15: 15 (weight ratio), potassium sulphate 58-60 jin.Planted behind the potato seedling the every mu of 200-300 cubic meter that waters 30-40 days.

(4) spray 80% short pin tiger soluble powder in sweet potato middle and later periods of growing: respectively carried out foliage-spray one time in the 50th day, 60 days and 70 days behind the potato seedling of planting, the every mu of amount of spraying is converted 30 kilograms in water for the 50g pulvis.

Sweet potato will in time be gathered in the crops: lunar calendar solar term were finished results before the Frost's Descent.Preventing that sweet potato from being damaged to plants caused by sudden drop in temperature influences processing quality.

Preferably, it is to adopt height to cut the seedling technology to transplant that step (2) is transplanted the sweet potato seedling, promptly from the potato seedling of the long 15-20cm of the seedbed clip land for growing field crops of planting.

Preferably, carbendazim is the blue rich board 50% pure product carbendazim that Jiangsu Lam Fung Biological Chemical Co., Ltd produces in the step (1), and add water and spray consumption after by 800 times of dilutions: every mu sprays 1350 liters ± 50 liters of dilute solutions.

Preferably, 80% short pin tiger soluble powder is the 80% short pin tiger soluble powder that Earthquake of Anyang station in Henan city complete rich pesticide chemical Co., Ltd produces in the step (4).Short pin tiger is a plant growth regulators, and main component is a paclobutrazol, and mechanism of action is the biosynthesis that suppresses plant body inner gibberellin.Its major physiological function is to prevent plant excessive growth, promotes reproductive growth, and the plant internode is shortened, and looks short, strong, thick, the plant type compactness, and well developed root system, resistant to lodging, chlorophyll content increases, drought resisting, cold-resistant, anti-saline and alkaline.

Biological organic fertilizer can be farmyard manure or chemical fertilizer in the step (3), and commodity biological organic fertilizer market is on sale, as the A Musi biological organic fertilizer of Beijing Century Aims Biotechnology Co., Ltd's production.The relevant technologies standard is referring to " biological organic fertilizer " standard of The Ministry of Agriculture of the People's Republic of China, MOA's announcement on January 4th, 2005.

Technical characterstic of the present invention is as follows:

1) generation of control black spot: when cultivating Rhizoma Dioscoreae esculentae No. 18 sweet potato seedling in the seedbed, the blue rich board 50% pure product carbendazim that available Jiangsu Lam Fung Biological Chemical Co., Ltd produces, by spraying around potato piece and the seedbed 1 meter after 800 times of dilutions with interior zone, adopt height to cut seedling and plant the land for growing field crops, select the anosis plot of not planting sweet potato more than 2 years for use.The anti-black spot ability of Rhizoma Dioscoreae esculentae No. 18 sweet potato a little less than, adopt above method can effectively control the generation of black spot, guarantee that the potato piece plant does not out have scab, has improved the quality of material potato.

2) select sandy loam for use: the soil of selection comprises, mountain region, hilly upland and Plain sandy loam.Select the higher sandy loam of physical features for use, help the potato piece and expand, rainy season, drainage effect was better, prevented that accumulated water from causing cauline leaf excessive growth in mid-term and later stage potato piece quality to descend, and influences baking properties.

3) plant rational close planting evening: at the beginning of 6 months, plant Rhizoma Dioscoreae esculentae No. 18 potato seedling, planting density is 4000-4500 strain/mu in good time.Planting density height than common sweet potato has guaranteed yield and quality, and table 1 is planted the phase plantation for Rhizoma Dioscoreae esculentae No. 18 in difference, the content of every index in Rhizoma Dioscoreae esculentae No. 18 sweet potato during harvesting.As seen from Table 1, than the late interior dry matter content decline of Rhizoma Dioscoreae esculentae No. 18 sweet potato, fiber content decline, tiny, the amylopectin content rising of fiber of planting 1 month of the phase of normally planting, the optimum dry matter content of processing request material potato of high-quality low sugar purple sweep potato dried meat is 25-27%, easily saccharification, fiber content is few, amylopectin content is high, pigment content is high and colouring evenly, can make so just that the potato dried meat that processes is just understood the quality softness, viscosity is good, color and luster is evenly translucent, mouthfeel is good, unbroken noodles, no white batch.

Table 1

4) rich water quality management: execute 300 jin of biological organic fertilizers (the A Musi biological organic fertilizer that the Beijing Century Aims Biotechnology Co., Ltd produces) for every mu before the whole ground ridging, 60 jin of nitrogen-phosphorus-potassium compound fertilizers, nitrogen wherein: phosphorus: the potassium weight ratio is 15: 15: 15,60 jin of potassium sulphates, planted behind the potato seedling the every mu of 200-300 side of watering 30-40 days.For the potato dried meat colouring that guarantees to process evenly, need to reduce dry matter content and fiber content, and the main means that reduce dry matter content and fiber content need be watered exactly planting the back in 30-40 days to sweet potato.As can be seen from Table 2,2-3 percentage point of the dry matter content decline that the ratio that watered in 30-40 days after planting does not water, fiber content descends.

Table 2

?	Water	Do not water
			Dry matter content	25-27％	28-30％
Fiber content	Less, carefully	Many, slightly

5) spray 80% short pin tiger soluble powder (the complete rich pesticide chemical in Earthquake of Anyang station in Henan city Co., Ltd produces) breeding time: spray short pin tiger pulvis in the sweet potato fertility middle and later periods, foliage-spray respectively carries out one time for behind the potato seedling of planting the 50th day, 60 days and 70 days, the every mu of amount of spraying is 50g, converts 30 kilograms in water.As seen from Table 3, therefore the processing that sprays short pin tiger pulvis sprays the content that short pin tiger pulvis helps to improve pigment in the sweet potato than not spraying the interior pigment content raising of sweet potato unit more than 2 that short pin tiger pulvis grows in good time.

Table 3

?	Spray short pin tiger pulvis	Do not spray short pin tiger pulvis
			Pigment content	18.56mg/100g	16.49mg/100g

The present invention cultivates the application of the sweet potato of acquisition

The Rhizoma Dioscoreae esculentae No. 18 sweet potato of adopting the above cultivation method plantation of the present invention to obtain is used to process low sugar purple sweep potato dried meat, and process steps is as follows:

1) selection of raw material: select epidermis smooth, no bar ditch and cracking, the Rhizoma Dioscoreae esculentae No. 18 potato piece of no scab;

2) shaping: Rhizoma Dioscoreae esculentae No. 18 potato piece water is cleaned up the back peeling, be cut into sweet potato chip or sweet potato;

Described sweet potato chip, long 4-6cm, wide 0.4-0.8cm is thick: 0.4-0.8cm,

Described sweet potato, long 4-6cm, wide 2-5cm, thick 0.2-0.3cm.

3) boiling: the sweet potato chip that cuts or sweet potato are gone into pot add the water boiling to well-done fully;

4) low saccharification is handled: pull out after well-done sweet potato chip or sweet potato are put into the cylinder infusion 20-24h that fills syrup; The weight ratio of described syrup is a sugar: water=1: 50;

5) alternating temperature baking, carry out according to the following steps stage by stage:

Painted baking: sweet potato chip or sweet potato that the low saccharification of step 4) is handled are spread out, placed on stainless steel grill, with the roasting 3-4h of 115 ℃-120 ℃ temperature, per hour upset once;

Fixation baking: with painted baking sweet potato chip or sweet potato take out back normal temperature cooling 0.5h, place then under 80-85 ℃ the temperature and toast 6-8h, the centre is stirred 2-3 time;

Moisture regain: 10-12h in the container that sweet potato chip that fixation was toasted or sweet potato place little ventilation hole;

Baking eases back: under 50-55 ℃ temperature sweet potato chip or sweet potato are dried once more, every 4h stirs and checks that once this stage needs 8-12h; Baking is finished the water content of back sweet potato chip or sweet potato at 22-30%, and about even;

6) post processing

With sweet potato chip or the sweet potato vacuum packaging after the baking, vacuum 0.095-0.1MPa; Carry out autoclaving again: steam pressure 0.08Mpa, sterilization time 15min; Change over to after the sterilization in 30 ℃ of ponds and cool off 0.5h.

Useful excellent results of the present invention is:

1, selects the higher sandy loam of physical features, and note the drainage waterlogging prevention in rainy season, help the potato piece and expand, improve the baking properties of material potato, guarantee that the French fries mouthfeel that processes is good.

2, the beneficial effect that lagged behind 1 month is to guarantee that the dry matter content of producing the Rhizoma Dioscoreae esculentae No. 18 sweet potato descends, fiber content descends, fiber is tiny, amylopectin content rises the phase of planting of sweet potato seedling, and the potato dried meat that processes is so just understood the quality softness, viscosity is good, color and luster is evenly translucent, mouthfeel is good, unbroken noodles, no white stubble.

3, the beneficial effect of strengthening rich water quality management breeding time is to guarantee that the dry matter content of producing the Rhizoma Dioscoreae esculentae No. 18 sweet potato descends, fiber content descends, the potato dried meat quality softness that can guarantee like this to process, colouring evenly, unbroken noodles, no white stubble.

4, control blackspot pathogenetic beneficial effect is to guarantee that the material potato of producing does not have scab, has improved the quality of raw material, has guaranteed the French fries pure taste that processes, and color and luster is vivid.

5, the beneficial effect that sprays paclobutrazol breeding time is to improve pigment content, can guarantee that like this potato dried meat that processes has the color of uniformity, has guaranteed looking good, smell good and taste good of product.

6, the present invention select for use high-quality purple potato meat the sweet potato new varieties---Rhizoma Dioscoreae esculentae No. 18 is processed into preserved sweet potatoes, it has quality softness, low, the translucent characteristics of color and luster of sugar content, and is rich in anthocyan and selenium element, and is anti-oxidant, it is strong to remove the free radical ability; Remove the free radical ability and be VE 20 times, 50 times of VC.This characteristic, to angiocardiopathy preventing, antitumor, mutation, radioresistance, delay senility, improve immunity of organisms, the anti-cancer and cancer-preventing effect is obvious.

7, new technology adopts the method for alternating temperature baking, with sweet potato cleaning, shaping, boiling, low saccharification, then through painted baking, fixation baking, the baking several stages gets damp again and eases back.The product color that processes is bright-coloured, and transparent feel is arranged, and the French fries water content is at 24-30%, and the inside and outside is evenly, good toughness, and sugariness is low, and has kept original nutrient component in the sweet potato in the process of oven dry, has made full use of the real value of purple sweep potato.

8, traditional handicraft also adds some pigments and preservative except carrying out the saccharification processing, is unfavorable for health care.New technology is not added any pigment and preservative except carrying out suitable low saccharification handles, and product is raw materials used itself just has healthy nutritive value.

Embodiment

The present invention will be further described below in conjunction with embodiment, but be not limited thereto.

Used Rhizoma Dioscoreae esculentae No. 18 potato seed is the kind that Crop Inst. of shandong Prov. Agriculture science Academy breeds among the embodiment, carbendazim is the blue rich board 50% pure product carbendazim that Jiangsu Lam Fung Biological Chemical Co., Ltd produces, 80% short pin tiger soluble powder is that Earthquake of Anyang station in Henan city complete rich pesticide chemical Co., Ltd produces, and biological organic fertilizer is the A Musi biological organic fertilizer that the Beijing Century Aims Biotechnology Co., Ltd produces.

Used PE or the composite evacuated packaging bag of PAP are that Guangdong grand sincere packaging material Co., Ltd produces thickness 0.07mm among the embodiment.

Embodiment 1, and the Rhizoma Dioscoreae esculentae No. 18 sweet potato obtains by following cultivation method, and step is as follows:

A kind of sweet potato that is used for preserved sweet potatoes processing is characterized in that obtaining by following cultivation method:

(1) selecting Rhizoma Dioscoreae esculentae No. 18 potato seed piece to carry out the seedbed cultivates, spray around potato seed pieces and the seedbed 1 meter with interior zone with 800 times of dilutions of carbendazim, consumption: every mu sprays 1400 liters of dilute solutions, disposable sprinkling when growing seedlings, and the seedbed is cultivated and was obtained Rhizoma Dioscoreae esculentae No. 18 sweet potato seedling in 35 days.

(2) select the anosis sandy loam plot of the sweet potato of not planting more than 2 years for use, at the beginning of 6 months of the annual Gregorian calendar, the Rhizoma Dioscoreae esculentae No. 18 sweet potato transplantation of seedlings that step (1) is cultivated is to the land for growing field crops, planting density is 4000-4500 strain/mu, adopt height to cut the seedling technology and transplant, promptly from the potato seedling of the long 15-20cm of the seedbed clip land for growing field crops of planting.

(3) before the whole ground ridging every mu execute 300 jin of biological organic fertilizers, 60 jin of nitrogen-phosphorus-potassium compound fertilizers, wherein nitrogen: phosphorus: potassium=15: 15: 15 (weight ratio), 60 jin of potassium sulphates, behind the potato seedling of planting the 35th day, the every mu of 200-300 side of watering.

(4) spray 80% short pin tiger soluble powder in the sweet potato fertility middle and later periods: respectively carried out foliage-spray one time in the 50th day, 60 days and 70 days behind the potato seedling of planting, the every mu of amount of spraying is 50g, converts 30 kilograms in water.

(5) results: lunar calendar solar term were finished results before the Frost's Descent.Preventing that sweet potato from being damaged to plants caused by sudden drop in temperature influences processing quality.

Embodiment 2, adopt the Rhizoma Dioscoreae esculentae No. 18 sweet potato of the cultivation method plantation acquisition of embodiment 1, are used to process low sugar purple sweep potato dried meat, and process steps is as follows:

1) selection of raw material: select epidermis smooth, no bar ditch and cracking, the Rhizoma Dioscoreae esculentae No. 18 potato piece of no scab;

2) shaping: Rhizoma Dioscoreae esculentae No. 18 potato piece water is cleaned up the back peeling, be cut into sweet potato chip or sweet potato;

Described sweet potato chip, long 5cm, wide: 0.5cm is thick: 0.5cm, the length of described sweet potato: 5cm, wide: 3cm is thick: 0.2cm;

3) boiling: the sweet potato chip that cuts or sweet potato are gone into pot add the water boiling to well-done fully;

4) low saccharification is handled: pull out after well-done sweet potato chip or sweet potato are put into the cylinder infusion 20-24h that fills syrup; The weight ratio of described syrup is a sugar: water=1: 50;

5) alternating temperature baking, carry out according to the following steps stage by stage:

Painted baking: sweet potato chip or sweet potato that the low saccharification of step 4) is handled are spread out, placed on stainless steel grill, with the roasting 3h of 120 ℃ temperature, per hour upset once; After this stage finished, the color of sweet potato chip or sweet potato was a slightly gloss of purple.

Fixation baking: with painted baking sweet potato chip or sweet potato take out back normal temperature cooling 0.5h, place then under 80 ℃ the temperature and toast 6h, the centre is stirred 2-3 time; After this stage finished, did on the surface of sweet potato chip or sweet potato, omit duricrust, but do not ftractureed, and lovely luster has transparent feel, surperficial tack-free.

Moisture regain: 12h in the container that sweet potato chip that fixation was toasted or sweet potato place little ventilation hole; Hand is glued on the sweet potato chip after this phase process or the surface of sweet potato, and the epidermis duricrust disappears, and about soft or hard basically identical, color and luster are dim slightly partially.

Baking eases back: under 50 ℃ temperature sweet potato chip or sweet potato are dried once more, every 4h stirs and checks that once this stage needs 10-12h; Baking is finished the water content of back sweet potato chip or sweet potato at 24-30%, and about even;

6) post processing

With sweet potato chip or the sweet potato vacuum packaging after the baking, vacuum 0.095-0.1MPa; Carry out autoclaving again: steam pressure 0.08Mpa, sterilization time 15min; Change over to after the sterilization in 30 ℃ of ponds and cool off 0.5h.

Process equipment: 101-0A type digital display type Constant Temp. Oven, common steamer.

Other NM equipment is existing equipment.

Embodiment 3

As described in embodiment 2, difference is:

5) alternating temperature baking, carry out according to the following steps stage by stage:

Painted baking: sweet potato chip or sweet potato that the low saccharification of step 4) is handled are spread out, placed on stainless steel grill, with the roasting 3h of 115 ℃ temperature, per hour upset once; After this stage finished, the color of sweet potato chip or sweet potato was a slightly gloss of purple.After this stage finished, the color of sweet potato chip or sweet potato was a slightly gloss of purple.

Fixation baking: with painted baking sweet potato chip or sweet potato take out back normal temperature cooling 0.5h, place then under 80 ℃ the temperature and toast 8h, the centre is stirred 2-3 time; After this stage finished, did on the surface of sweet potato chip or sweet potato, omit duricrust, but do not ftractureed, and lovely luster has transparent feel, surperficial tack-free.

Moisture regain: 10h in the container that sweet potato chip that fixation was toasted or sweet potato place little ventilation hole; Hand is glued on the sweet potato chip after this phase process or the surface of sweet potato, and the epidermis duricrust disappears, and about soft or hard basically identical, color and luster are dim slightly partially.

Baking eases back: under 55 ℃ temperature sweet potato chip or sweet potato are dried once more, every 4h stirs and checks that once this stage needs 12h; Baking is finished the water content of back sweet potato chip or sweet potato at 24-30%, and about even;

Embodiment 4

As described in embodiment 2, difference is:

The step 5) alternating temperature baking stage:

Painted baking: sweet potato chip or sweet potato that the low saccharification of step 4) is handled are spread out, placed on stainless steel grill, with the roasting 3h of 115 ℃ temperature, per hour upset once; After this stage finished, the color of sweet potato chip or sweet potato was a slightly gloss of purple.

Fixation baking: with painted baking sweet potato chip or sweet potato take out back normal temperature cooling 0.5h, place then under 85 ℃ the temperature and toast 7h, the centre is stirred 3 times; After this stage finished, did on the surface of sweet potato chip or sweet potato, omit duricrust, but do not ftractureed, and lovely luster has transparent feel, surperficial tack-free.

Moisture regain: 11h in the container that sweet potato chip that fixation was toasted or sweet potato place little ventilation hole; Hand is glued on the sweet potato chip after this phase process or the surface of sweet potato, and the epidermis duricrust disappears, and about soft or hard basically identical, color and luster are dim slightly partially.

Baking eases back: under 50 ℃ temperature sweet potato chip or sweet potato are dried once more, every 4h stirs and checks that once this stage needs 8h; Baking is finished the water content of back sweet potato chip or sweet potato at 22-24%, and about even.

Claims (1)

1. the processing method of a preserved sweet potatoes, step is as follows:

1) selection of raw material: select epidermis smooth, no bar ditch and cracking, the Rhizoma Dioscoreae esculentae No. 18 potato piece of no scab;

2) shaping: Rhizoma Dioscoreae esculentae No. 18 potato piece water is cleaned up the back peeling, be cut into sweet potato chip or sweet potato;

Described sweet potato chip, long 4-6cm, wide 0.4-0.8cm is thick: 0.4-0.8cm; Described sweet potato, long 4-6cm, wide 2-5cm, thick 0.2-0.3cm;

3) boiling: the sweet potato chip that cuts or sweet potato are gone into pot add the water boiling to well-done fully;

4) low saccharification is handled: pull out after well-done sweet potato chip or sweet potato are put into the cylinder infusion 20-24h that fills syrup; The weight ratio of described syrup is a sugar: water=1: 50;

5) alternating temperature baking, carry out according to the following steps stage by stage:

Painted baking: sweet potato chip or sweet potato that the low saccharification of step 4) is handled are spread out, placed on stainless steel grill, with the roasting 3-4h of 115 ℃-120 ℃ temperature, per hour upset once;

Fixation baking: with painted baking sweet potato chip or sweet potato take out back normal temperature cooling 0.5h, place then under 80-85 ℃ the temperature and toast 6-8h, the centre is stirred 2-3 time;

Moisture regain: 10-12h in the container that sweet potato chip that fixation was toasted or sweet potato place little ventilation hole;

Baking eases back: under 50-55 ℃ temperature sweet potato chip or sweet potato are dried once more, every 4h stirs and checks that once this stage needs 8-12h; Baking is finished the water content of back sweet potato chip or sweet potato at 22-30%, and about even;

6) post processing

With sweet potato chip or the sweet potato vacuum packaging after the baking, vacuum 0.095-0.1MPa; Carry out autoclaving again: steam pressure 0.08Mpa, sterilization time 15min; Change over to after the sterilization in 30 ℃ of ponds and cool off 0.5h; Described Rhizoma Dioscoreae esculentae No. 18 potato piece obtains by following cultivation method:

(1) select Rhizoma Dioscoreae esculentae No. 18 potato seed piece to carry out the seedbed and cultivate, spray around potato seed pieces and the seedbed 1 meter with interior zone with 800 times of dilutions of carbendazim, every mu of consumption 1300-1400 rises dilute solution, disposable spraying when growing seedlings; The seedbed is cultivated and was got Rhizoma Dioscoreae esculentae No. 18 sweet potato seedling in 30-40 days;

(2) select the anosis sandy loam plot of the sweet potato of not planting more than 2 years for use, at the beginning of 6 months of the annual Gregorian calendar, the Rhizoma Dioscoreae esculentae No. 18 sweet potato transplantation of seedlings that step (1) is cultivated is to the land for growing field crops, and planting density is 4000-4500 strain/mu; Described transplanting sweet potato seedling is to adopt height to cut the seedling technology to transplant, from the potato seedling of the long 15-20cm of the seedbed clip land for growing field crops of planting;

(3) every mu of fertilising is as follows before the whole ground ridging: biological organic fertilizer 280-300 jin, nitrogen-phosphorus-potassium compound fertilizer 55-60 jin, wherein nitrogen: phosphorus: potassium=15: 15: 15 weight ratios, potassium sulphate 58-60 jin, behind the potato seedling of planting 30-40 days, the every mu of 200-300 cubic meter that waters;

(4) spray 80% short pin tiger soluble powder in sweet potato middle and later periods of growing: respectively carried out foliage-spray one time in the 50th day, 60 days and 70 days behind the potato seedling of planting, the every mu of amount of spraying is converted 30 kilograms in water for the 50g pulvis.