Effect of microfluidization process on the functional properties of IDF

Effect of micro fluidization process on the functional properties of insoluble dietary fiber

Jialun Chen,Dongxiao Gao,Letian Yang,Yanxiang Gao ⁎

College of Food Science and Nutritional Engineering,China Agricultural University,Haidian District,Beijing 100083,PR China

a b s t r a c t

a r t i c l e i n f o Article history:

Received 30May 2013

Accepted 18September 2013Keywords:

Micro fluidization

Insoluble dietary fiber Functional properties Particle size

The effects of micro fluidization on the characteristics and physicochemical properties of insoluble dietary fiber

(IDF)from peach and oat were investigated.The results showed that micro fluidization could effectively reduce IDF particle sizes to submicron scales,trigger a redistribution of some fiber composition from insoluble to soluble fractions and improve the physicochemical properties (water-holding capacity,swelling capacity,oil-holding capacity)of IDF to some different extents.After micro fluidization the IDF ability in lowering postprandial serum glucose (including the effects of IDF on the diffusion of glucose,glucose adsorption capacity and inhibitory effects of IDF towards α-amylase)and the activity of pancreatic lipase generally increased.It was concluded that micro fluidization treatments could effectively improve the functionalities of IDF,which might be a potential fiber-rich ingredients in functional foods.

©2013Published by Elsevier Ltd.

1.Introduction

In the past two decades,many studies have revealed that an adequate consumption of dietary fibers can help improve intestinal health,lower blood lipid and cholesterol,and reduce the risk of coronary heart disease.Foods supplemented with dietary fibers are regarded as fitness-promoting,and low in calories,cholesterol and fat.Fiber source research has focused on tubers,cereals,vegetables,fruits,and algae (Miller Jones,2003;Slavin,2001;Vitaglione,Napolitano,&Fogliano,2008),all of which are characterized by high dietary fiber content with low digestibility and low caloric content (David,Alfredo,Gabriel,&Luis,2009).However,the fermentation of dietary fiber by anaerobic bacteria in the large intestine produces gas (including hydro-gen,methane and carbon dioxide),which may be related to complaints of distention or flatulence,especially with high intakes of fiber (Slavin,Savarino,Paredes-Diaz,&Fotopoulos,2009).

In recent years,the concepts of applying modi fication in fiber research and development have gained much attention.Chemical,mechanical,thermal and enzymatic processing can modify the proper-ties of insoluble dietary fiber (IDF).Chemical treatments with acidic or basic solutions of sugar beet fibers can increase the swelling capacity of IDF,which could be explained by the damage of the coherence of the cell walls (Bertin,Rouau,&Thibault,1988).Mechanical treatment,

such as extrusion,opens the fiber structure by mechanical shear,releasing free hydroxyl groups from cellulose available to bind with water.Choi et al.reported that extrusion improved physicochemical properties of IDF as a consequence of increasing surface area (Choi et al.,2008).Thermal treatments can change their physicochemical properties of dietary fiber by altering the ratio between soluble and insoluble fiber (SDF/IDF),total dietary fiber content.Caprez et al.reported that wet heat treatments of wheat bran affected the surface properties of dietary fibers and could lead to a signi ficant increase in oil holding capacity (OHC)(Caprez,Arrigoni,Amadò,&Neukom,1986).Enzymatic treatment can also change the ratio between soluble and insoluble fibers.Zhou et al.reported that the water holding capacity and swelling capacity of Tartary Buckwheat (Fagopyrum tataricum Gaertn)bran dietary fiber were improved after enzymatic treatment,due to the increasing of SDF/IDF and the decreased size of dietary fiber particles (Zhou,Qian,Zhou,&Zhang,2012).

At present,the application of micronization in food research and development is gaining much attention.Its application in food research proved that the reduction of particle size of food materials can not only alter their structure,surface area but also improve their functional properties (Ogawa,Decker,&McClements,2003;Raghavendra,Rastogi,Raghavarao,&Tharanathan,2004;Sangnark &Noomhorm,2003).For example,grinding increases and decreases the hydration properties of the same material,depending on its particle size.Raghavendra reported that the decrease in the particle size of coconut fiber,from 1127to 550μm,resulted in an increase in hydration properties (Raghavendra et al.,2004).Chau et al.demonstrated that physicochemical properties of carambola insoluble fiber depend not only on the extent of grinding (fiber particle size)but also affected by different micronization tech-niques (Chau,Wen,&Wang,2006b ).

Food Research International 54(2013)1821–1827

Abbreviations:DF,dietary fiber;IDF,insoluble dietary fiber;SDF,soluble dietary fiber;WHC,water holding capacity;SC,swelling capacity;OHC,oil holding capacity.

⁎Corresponding author at:P.O.Box 112,No.17Qinghua East Road,Haidian District,Beijing 100083,PR China.Tel.:+861062737034;fax:+861062737986.

E-mail address:gyxcau@ (Y.Gao).0963-9969/$–see front matter ©2013Published by Elsevier Ltd.Contents lists available at ScienceDirect

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