韓吉慶 張 慧 姜傳世 崔振蕾

（青島大學(xué)化學(xué)科學(xué)與工程學(xué)院，山東 青島266071）

0 Introduction

Ginger is a perennial herbaceous perennial plant.It native to tropical areas of Southeast Asia,later spread into China and become an important spice and herbs.In China,ginger is essential,its unique spicy taste was recognized by the Chinese people in ancient times；while ginger is also as a medicine in China,the ginger rhizome,cork and leaves can be used as medicine,ginger has a divergence,vomiting,cough and other effects in Chinese medicine.

1 Extraction

Ginger oleoresin usually stored in the void of rhizome angular cells.It distributed both in interior and epidermis of the rhizome,and it is more in the epidermal tissue,so one of the important factors affecting the yield of ginger oil is whether the ginger peeled.In addition,it has a greater impact on the composition and quality of ginger oil across different drying treatments to the ginger before extracting ginger oil.It will lost many low boiling terpenoid when drying the Fresh ginger.Therefore,it has a greater impact on the volatile ginger oil components in addition to pretreatment process.Research shows that it is efficient and does not reduce the active components in biological to using far infrared drying processing the ginger.At the same time,the yield,flavor and spicy of ginger oleoresin is related with extraction method.At present the extraction of ginger oleoresin mainly has the following several.

1.1 The water vapor distillation

The steam distillation is the most common method to extract volatile oil from ginger,it using Dalton's law of partial pressures to separate volatile component which is difficult to dissolve in water.Firstly,mashing the fresh ginger before distillation,then at atmospheric pressure or under pressure,passing into the water vapor to make ginger oil distillate at temperatures below the boiling point.This method is mainly to obtain high volatile oil from the ginger but the low volatile portion,so the water vapor distillation can just extract part of ginger oil in ginger and the oil production rate is low.

1.2 Solvent extraction

Solvent extraction including direct solvent immersion and Soxhlet extraction,the former is to put solid ginger directly soaked in the solvent to enable the effective components that contained in ginger were extracted according to certain rules(such as Fei Ke's law)；the latter is to use the siphon principle,make the effective component of solid ginger continuously and repeatedly extracted by the pure solvent.The chemical composition that contained in Ginger oleoresin which obtained above two extraction is related to the selection of solvent.It is mostly use strong polarity solvents,such as ether,acetone,methanol,ethanol and ethyl acetate and it can increase the yield when using continuous ethanol Soxhlet extraction.With this method,we must recycle the solvent,to provide a large amount of heat energy while it inevitably introduce another substance into the target product and affect the quality of the product.

1.3 Supercritical CO2 fluid extraction

It is using liquid with high pressure as the extraction solvent to obtain both the components of volatile oil and other non volatile component such as oleoresin.This method has the mild reaction condition and high extraction efficiency.It has an irreplaceable role in the retention of flavor and spicy.It is a new and high technology that develops quickly in recent twenty years and using CO2as the supercritical fluid to take ginger oil out,then the ginger oil will be released from the CO2fluid which will transformate through supercritical state to a gaseous phase.The advantage of this method is to avoid the defects of steam distillation and solvent extraction.CO2is a kind of environment friendly inert material which does not have any side product and solvent residue.In addition,it has highly selective and can make the different set of ginger oil and oleoresin in separation.

2 Application

2.1 sauce

Ginger oleoresin is the main material presented aroma and spicy taste of ginger.It can be used as a high-quality concentrated seasonings instead of traditional spicy materials to be used in food processing and cooking.

2.2 natural antioxidant

As the main material of ginger oleoresin,the gingerol has a strong antioxidant that can be used as a·OH scavenger.The ginger is a good ingredient that is in line with eating habits of consumer,so extract the strong antioxidant amaterial that is efficient and economic is an important way to further develop natural food antioxidants.

2.3 ginger tea drink

Ginger oleoresin contains all the aroma and flavor of the ginger which is spicy,hot and has the functions on stomach,so it can be used as the main ingredients of solid ginger tea drink.At present,many domestic enterprises have producted solid ginger tea drink,developed many tastes and it looks promising.

2.4 stomach vomiting

Ginger is the recipe of treating spleen,stomach and anti-emetic in folk.Studies show that ginger can stimulate the synthesis of gastric mucous membrane and release the endogenous Pepsinogen which have a cytoprotective effect,so as to protect the gastric mucosa against injury[2].The extract of ginger that through acetone has the anti-gastric ulcer effect which induced by hydrochloric acid and ethanol,the effective components of the extraction is shogaol.

2.5 anti-inflammatory and analgesic

Studies show that ginger oil orally could significantly inhibit ear inflammation that induced by histamine and acetic acid,inhibit the proliferation of granulation tissue,reduce thymus weight of juvenile mice.Ginger oil could obviously inhibit the swelling of rat’s claw and joint and has the effect of anti-inflammatory and anti-rheumatism.The injection of Fresh ginger has the anti-inflammation and detumescence effects on formaldehyde swollen of rats feet[3].In a word,the ether extraction and the water extraction of ginger have an anti-inflammatory effect.S

［1］Weiss E.A.Essential Oils Crops,Eaglemont,Australia.1997：539-567.

［2］Eva Bryer,CNM.A literature review of the effectiveness of ginger in alleviating mild-to-moderate nausea and vomiting of pregnancy[J].Journal of Midwifery&Women,s Health,2005,50：1-3.