Download Continued Development Theory and Practice of Sweet Potato Industry

Continued Development Theory and Practice of Sweet Potato
Industry
GAO Haisheng, LIU Xiufeng, JIA Yanru
Department of Food Engineering, Hebei Normal University of Science and Technology, Qinhuangdao,
Changli, P.R.China, 066600
[email protected]
：
Abstract This article sincerely introduces current situation of the sweet potato industry at the basic of
its nutritional and healthcare functions, introduced series of sweet potato production which have been
exploited or not been exploited beside the prospective analysis of potato industry development, and it
included the following points: Firstly, improve and deeply process of the sweet potato starch quality.
Secondly, exploitation of sweet potato amylase technology; Thirdly, preparation of sweet potato dietary
fiber; Fourthly, the extract technology of sweet potato active ingredient, polysaccharide and protein. It
proposed the continuing developing measure of sweet potato industry. First we should improve scientific
level of sweet potato breeding, and then improve the research of the sweet potato breeding technology;
third, we should enhance the improvement of technology, widen product field; fourth, adopt sweet
potato circular economy, promote industry level.
Keywords: sweet potato, industry, continuing development, measure
1 Introduction---- The nutritional and healthcare functions of sweet potato
Besides starch, sweet potato also contains protein, fat, vitamins, amino acids, calcium, phosphorus, iron
and other minerals. Chinese medicine think that sweet potato has sweet and smooth taste, non-toxic, to
notifying spleen and stomach, can raise mind, strength power, smooth latex, and eliminate the position
that left the first day in the gut .Results of recent studies showed that the sweet potato, in addition to
polyphenols, vitamins, dietary fiber, contain nutritional and medicinal ingredients such as anthocyanin,
β-carotene, gangliosides, jalapn. The parts from which to the skin about 5-10mm away contain more
anthocyanin, chlorogenic acid, Jalapin and calcium, these nutrient substance have the action of
antioxidant, can repair the damage liver, resist cancer, and hypertension, inhibit bacteria breeding, resist
inflammation, promoting bowel movements and prevent ultraviolet radiation, etc, in which anthocyanin
plays a major role. Anthocyanin maintains stability in the heating, cooking process, without losing the
original activity even in the storage and processing it will not be destroyed and has a good value of
utilization [1].
Sweet potato also contains active substances ----prasterone, dehydroepiandrosterone, which have special
effect to the human body and can delay the body senescence and enhance immunity.
The study found that purple sweet potato tuber has strong anti-mutagenicity and prove that chlorogenic
acid and other types of polyphenols can prevent cumulation of cancergenic during food processing and
cooking process.
In addition, the experiment also showed that the ganglioside containing in the sweet potato juice can
control appreciation of artificially cultured human HeLa cells (cervical cancer) and B-16 cells
(melanoma, a skin cancer), and can also convert the cancer cell into healthy one. Scientific research
discovered that the DHEA (dehydroepiandrosterone) only the sweet potato contains can prevent colon
cancer and breast cancer. Survey shows that the sweet potato can strongly control the split speed of
cancer cell through the test of 82 kinds of vegetable juice and vegetable ingredient to the cell division
and splitting. JNIH proved that the sweet potato has the best anti-cancer effect in 40 kinds of anti-cancer
vegetables [1].
2 Production status of sweet potato industry
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According to the statistics of the FAO, there are 111 countries in the world cultivate sweet potato, and
the cultivation area mainly lies in the developing countries such as Asia, Africa, then followed by Latin
America. The area in Europe is the least. According to the reports, the world's sweet potato cultivation
area is 9.046 million hm2, of which 97.9% is in developing countries. And the total output is 136.756
million tons.
China has a long history of sweet potato cultivation, since the late 16th century, sweet potatoes were
introduced to China from Philippines, Vietnam, Myanmar, India and other places and has a history of
more than 400 years; during 17-l8 century sweet potato were widely cultivated in China and the area
expanded to 1 million hm2 in1960s.The sweet potato become one of four kinds of drop plants which
contain wheat, rice and corn in China [2].
In 1960s, in order to solve dining and dressing problem people enlarged the cultivation of sweet
potato ,then make the sweet potato as feedstuff later ,the conception that sweet potato is a kind of plant
which is not worthy and just for feeding has formed. So the farmers planted it in arid soil, did not turn
the soil deeply, hardly fertilize and always delay the plant date, they did not take good care of them even
if planted it at time. The sweet potato region has carried out a “five-change” policy: change over to
excellent breed, change late cultivate to suitable cultivate, change wide planting to suitable thick
planting, adapt suitable and scientific fertilize method, intensive management in 1980s, and it played an
important effect in increasing production, while the phenomenon that “five-change” technology did not
spread steadily and not widely used, and the skill cannot reach the designated position on time, the
cultivate technology is relatively backward, extensive management is quite serious. In recent years,
insect pest of the sweet potato seems to be more serious than before and have influenced the yield.
As technology developed, people gradually realized that during the insect pest which is mischievous to
sweet potato production, the virosis has become a major obstacle in increasing the sweet potato yield. So
China has succeeded in studying the sweet potato virus-free technology which is remarkable in
increasing yield. Making up planting process of sweet potato virus-free technology which contains the
process such as selection of superior varieties, the culture of the stem tine–cleavage structure, virus-free
identification, fast breeding propagate in cuvette, producing of original breed (improved type) and
potato breed virus detection. Since popularized, this technology received farmers, popularities and
become an important technique in pushing sweet potato production. [2]
3 Develop prospect analysis of sweet potato product
Sweet potato is not only an important guarantee of foodstuff security, an important source of health food,
but also an important way of increasing farmers, income. Sweet potato industry should convert to
high-nutrition food as coarse grains to promote its sustainable development.
3.1 Series of sweet potato products which have been exploited currently
With sweet potato as raw material, we can produce alcohol, distilled spirit, monosodium glutamate,
citric acid, lactic acid by fermentation; the production fructose, starch sugar, maltose are made by
GOD-POD. In addition, sweet potato also can be widely used in making the butyric acid, butanol,
acetone, amino acids, enzymes, modified starch, starch derivatives, etc in recent years, and it has a
certain development. In the aspect of food exploitation, the sweet potato can be divided into two kinds,
fermentation and non-fermented foods. The former mainly include: soy sauce, vinegar, fruit beer
beverages, lactic acid fermented beverage of sweet potato; the latter included vermicelli, vermicelli type,
preserved fruits category, sweet potato jam, snacking foods (such as crisp fried potato chips, fried sweet
potato chip), pastry class (sweet potato dessert, mashed potato), sweets (candy, caramel), drinks (sweet
potato milk), ice cream, vegetables (dehydrated vegetables, salted vegetables) and other products.
Besides the sweet potato starch exploitation, most of the products are processed at the cottage-style
model with low value-added product, and the economic benefit is not high.
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3.2 The urgent new sweet potato products which need development
(1) Quality improvement and deep processing of sweet potato starch
Our country's annual output of sweet potato starch is over 2 million tons, while the refined starch is only
20 million tons, less than 10% of the total quantity, and the scale of the starch which is deeply processed
into modified starch and other chemicals and pharmaceutical products is small. Sweet potato starch has
the unique characteristic such as high-viscosity, high degree of polymerization, high film-forming, mild
taste, non-stimulation compared to grain starch such as the maize with typical grain taste, so it is
suitable for fruit cans with mild taste, swelling food, flavoring food, vanilla pudding-rich food and it did
not produce any other effect that hide other flavor.
Improve products of sweet potato starch:
modified starch. The main products are oxidized starch,
acid starch, starch esters, cross-linked starch, cationic starch, grafted starch and so on .They are widely
used in the textile, papermaking, medicine, food, building materials, casting, light industry, petroleum,
Chemical
energy, feed, agriculture, environmental protection, bio-engineering and other industries.
products. Organic chemical products which are produced through fermentation with the potato starch,
there are oxalic acid, amino acids, polyethylene, acetic acid, epoxy ethane, sorbitol, ethanolamine etc.,
they are the important main raw material in making rubber, pesticides, grease, packaging materials,
cosmetics, military supplies. Hydrolysis products. With the sweet potato starch can produce the
hydrolyze glucose, fructose, maltose, oligosaccharide, trehalose and other products, as an emerging
healthcare food; it has become the new darling of the international confectionery market.
(2) Exploitation of sweet potato starch sugar technology
Improve the yield of sweet potato starch in immobilized enzyme technology, exploit sweet potato starch
sugar directly which have their own feature, study sweet potato starch sugar function feature and process
function in modern food science principles is maltose oligosaccharide can proliferate bifid bacterium,
prevent caries, multiple sugar alcohol has low calorific value, can prevent caries, maltose can take the
place of sucrose and prevent "back sand" in making candy and sweetmeat. Malt oligosaccharide can
enhance enduring of the athlete if it is added to sports beverage.
(3) Preparation of sweet potato dietary fiber
There are many ways on extracting dietary fiber and it has become a direction that extract sweet potato
dietary fiber from the residue that left when extracting starch in physical and biological methods.
(4) Extract technology of the sweet potato active ingredients, polysaccharides and protein
Extracting the active ingredient in ultrasonic and microwave technology and study the optimum
techniques parameters. Improve the rate of polysaccharide production in microwave extraction
technology and enhance the purity of sweet potato polysaccharide; extract sweet potato polysaccharide
according to the "double solution" [3]. Extract sweet potato protein in ultrasonic and microwave
technology; we can also make systematic research about the sweet potato protein solubility,
emulsification, gel formation and thermal stability, discuss its application characteristic in food
production technology as food nutritional supplements, food additives and functional active substances.
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4 The sustainable development measures of sweet potato industry
4.1 Improve the scientific research level of sweet potato breeding
High-quality breed variety is the basis of the sweet potato industry development. Therefore, we should
exploit appropriate high-quality and special-purpose type according to different needs, such as the high
starch, low polyphenol oxidase type which is suitable for starch producing, the high-sugar type suitable
for food machining, the herb sweet potato suitable for producing health-care food, vegetable type which
is suitable for stem processing, fruit type which is suitable for direct eating, the purple type suitable for
extract red pigment, meanwhile, we should make seed selection with double use even multiple uses
according to the conditions. For the type with multiple uses has stronger adaptive capacity with higher
and stable economic benefit. In the meantime, we should carry out survey work about the quality of
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sweet potato and fully distribute the action of existing excellent breed.
4.2 Enhance the research and extension of sweet potato cultivation
Improve production conditions of the sweet potatoes as much as possible, enhance soil fertility levels;
speed up the popularization and application of new varieties by using virus-free sweet potato seedling
technology and rapid propagation of sweet potato seedlings; enhance research and extension of
cultivation which is excellent, high yield, low spend on target according to the problems of thin planting
density ,a serious shortage of potash fertilizer use, management technological backwardness, pay much
attention to the cultivate technology of intercropping which combined application with support;
Establish typical training base, expedite the popularization and application of advanced suitable
technology in the main district of sweet potato.
4.3 Increase scientific and technological investment, expand production field
When promoting the transformation of existing technological achievements, we must further increase
power of technology investment and exploitation, carry out sweet potato product new processing rely on
technology advantage of research units and independent innovational capability of processing enterprise,
especially the research and development of sweet potato health protection and new production
processing technique such as the extraction and exploitation of food edible pigment and produce sweet
potato product with high additional value to raise economic efficiency.
In addition, due to the oil energy crisis recently, many countries compete to develop energy plants, sweet
potato is one kind. It is reported that 2.8 ~ 2.9 tons of dry sweet potato can produce 1 ton of ethanol, 8 to
10 tons fresh sweet potatoes produced 1 ton of ethanol, while produce the same amount of ethanol
require 3.2 tons of corn, 3.3 tons of wheat, absolutely, sweet potato can be used as an important energy
crops.
4.4 Carry out the sweet potato cycle economy, promote the industry level
Make the market as guidance, and the sweet potato processing enterprises as a leader, carry out
all-in-one mode with the production, processing and marketing ,namely, the formation "enterprise
(company) + base (farmer specialized cooperation) + farmers" . on the basis of this mode, carry out
sweet potato cycle economic, the sweet potato dregs can be used for alcohol manufacture, the lees and
potato stem can feed pigs, cattle and other livestock, after fermentation the manure can produce marsh
gas-a kind of clean energy- with the plant straw, and the pond dregs can be used as compound manure or
can be executed to sweet potato field directly after treating. It can promote the sweet potato grow and
raise the quality of sweet potato.
Government should strive to create excellent investment environment to attract capital investment to
promote the development of sweet potato processing industry. Guide the consumer and set up a brand
advantage of sweet potato processing product, we should seize the sweet potato characteristics that raw
materials are focusing on remote areas and is pollution-free, build up green card, processing companies
should apply to the departments to strive for the healthy food production licenses and green flag. At the
same time, improve product packaging design and figure plot of enterprise, promote product level.
Boost sales with brand advantage, and promote sustainable development of sweet potato industry.
References
[1]. Liu Shaojun. The fundamental health ---- potato nutrition [M]. Beijing: Beijing Norma University
Press, 2007.7 in Chinese
[2]. Tan Xigut. Prospects of China's sweet potato production [J]. Anhui Agricultural Science, 2004, 32
(1): 185,190 in Chinese
[3]. Wu Yuhua .The world's new trends in processing and utilization of sweet potato [J]. Food Research
and Development, 2003, 24 (5):5-8 in Chinese
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