Journal of Food Engineering 107 (2011) 319–325

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Journal of Food Engineering

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Edible coating and post-frying centrifuge step effect on qualityof vacuum-fried banana chips

Rungsinee Sothornvit ⇑Department of Food Engineering, Faculty of Engineering at Kamphaengsaen/Center of Excellence for Agricultural and Food Machinery, Kasetsart University,Kamphaengsaen Campus, Nakhonpathom 73140, Thailand

a r t i c l e i n f o a b s t r a c t

Article history:Received 30 September 2010Received in revised form 28 June 2011Accepted 9 July 2011Available online 21 July 2011

Keywords:Banana chipGuar gumXanthan gumVacuum fryingOil absorption

0260-8774/$ - see front matter � 2011 Elsevier Ltd. Adoi:10.1016/j.jfoodeng.2011.07.010

⇑ Tel.: +66 34281 098; fax: +66 3435 1404.E-mail address: fengrns@ku.ac.th

A high oil content in fried banana chips shortens the shelf life of the product and causes a decrease inproduct acceptability to consumers. The oil absorption problem associated with fried products mightbe reduced by using hydrocolloids as edible coatings and modifying the frying process during the oil cen-trifuge step of vacuum frying. The objective of this study was to determine the effect of edible coatingmaterials and the speed of the oil centrifuge step on the amount of oil absorption and the physical prop-erties of vacuum-fried banana chips. Compared with regular vacuum-fried products (control samples),banana chips coated with either guar gum or xanthan gum solutions at 1.5% or centrifuged at a higherspeed than standard conditions (from 140 to 280 rpm) reduced oil absorption by 25.22%, 17.22% and17.31%, respectively. Moreover, the combination of an edible coating and the higher centrifugation speedresulted in a greater reduction of oil absorption (33.71%) compared with control samples. Therefore,banana chips coated with an edible coating and produced using the higher speed during the oil centrifugestep in the vacuum-frying process maintained a good quality with low oil content, representing a health-ier snack for consumers.

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1. Introduction at a lower processing temperature. For example, vacuum-fried

Frying is a dehydration process which involves heat and masstransfer. In addition, different chemical changes occur during fry-ing such as starch gelatinization and protein denaturation, surfacebrowning, rapid water evaporation and oil absorption. Deep-fatfrying generally occurs at high temperatures under atmosphericpressure causing the absorption of a high amount of fat, whichcould be up to 50% of the total weight of the fried food (Pinthuset al., 1993). An increase in the fat content due to oil absorptionin fried foods has become a health problem associated with obesityand coronary heart disease. Oil absorption is affected by variousfactors such as frying temperature and time, food composition(for example, the moisture, solids, fat and protein contents), poros-ity, pretreatment (blanching and drying) and oil quality (Pinthuset al., 1993). Thus, there have been many efforts to reduce oilabsorption during the deep-fat frying of many products such aschickpeas (Annapure et al., 1999), potato strips (Garcia et al.,2002; Rimac-Brncic et al., 2004; Tran et al., 2007), chicken nuggets(Sahin et al., 2005), carrot slices (Akdeniz et al., 2006) and cerealproducts (Albert and Mittal, 2002).

Fruit and vegetables are heat sensitive; therefore, vacuum fry-ing is an alternative method to produce high quality fried products

ll rights reserved.

pineapple chips obtained at 24 kPa (112 �C for 7 min) had a goldenyellow color and retained total vitamin C, phenolic compounds andantioxidant capacity with low oil uptake (Perez-Tinoco et al.,2008). Processing at low temperature and pressure reduces theamount of oil penetrating into the material and the deteriorationand oxidation of the frying oil, resulting in stable fried food prod-ucts (Fan et al., 2005; Da Silva and Moreira, 2008). Compared withatmospheric frying, vacuum frying reduced oil content by 50% andkept higher contents of trans a- and b-carotene in carrot slices(Dueik et al., 2010). A strong relationship has been reportedbetween water loss and oil content with both atmospheric andvacuum-frying techniques (Mariscal and Bouchon, 2008). Moreiraet al. (2009) indicated that oil absorption occurs at the same timethat water evaporates from the samples. The amount of oil absorp-tion depended on the amount of free water and surface oil in theproduct. In this sense, the reduction in oil absorption in vacuum-fried apple slices compared to atmospheric frying was related toa reduction in moisture loss (Mariscal and Bouchon, 2008). None-theless, the vacuum frying process still involves a certain amountof oil absorption. Thus, a reduction in the oil content of fried prod-ucts would be the ultimate goal for both food manufacturers andconsumers. An additional way to reduce the oil content of friedproducts is by applying a higher speed in the post-frying centrifugestep in the vacuum fryer. Moreira et al. (2009) studied the effect ofvacuum frying equipped with a centrifuge as a de-oiling mecha-nism for potato chips. It was found that vacuum-fried potato chips

320 R. Sothornvit / Journal of Food Engineering 107 (2011) 319–325

centrifuged at 750 rpm had a lower oil content than those not cen-trifuged. The kinetics of oil content absorption increased exponen-tially during the first 120 s of frying and dropped slightly until theend of frying (Moreira et al., 2009).

Food hydrocolloids, such as gums, have been widely used as mul-tifunctional additives in food processing to improve stability,modify texture and control the moisture content (Rimac-Brncicet al., 2004; Chaisawang and Suphantharika, 2005). In addition,hydrocolloids have the ability to form edible films and coatings withgood oxygen, carbon dioxide and lipid barriers, which gives thempotential to reduce oil absorption in deep-fat-fried products (Albertand Mittal, 2002). Thus, edible films and coatings might protect foodfrom the oil absorption which occurs during the first frying period atthe same time as water evaporation occurs. The common hydrocol-loids used as edible films and coatings include gums, such as guarand xanthan, cellulose derivatives, such as methyl cellulose,hydroxypropyl cellulose and carboxymethyl cellulose, and otherpolysaccharides and proteins. Combinations of polysaccharidesand proteins have been successfully used in fried products. Forexample, using batter and breading formulations involving proteinand a polysaccharide (hydroxypropyl methylcellulose) on friedpoultry products reduced oil absorption up to 33.7% (Balasubr-amaniam et al., 1997). Several hydrocolloid types, including guarand xanthan gums at concentrations between 0.25% and 2.00%,were examined for their ability to reduce oil absorption in friedchickpea products (Annapure et al., 1999), with the results showingthat guar gum reduced the oil content by 30–33%. However, theapplication of hydrocolloids to banana chips has been very limited.Recently, Singthong and Thongkaew (2009) reported that the appli-cation of different polysaccharides (alginate, carboxyl methyl cellu-lose and pectin) reduced the oil absorption in deep-fat-fried bananachips between 2% and 17% depending on the edible coating compo-sition, which indicates the potential of edible coatings to reduce theoil uptake of fried products. Xanthan and guar gums are commonlyused in food formulations and no reported work has been found ontheir suitability as edible coatings on fried banana chips to reduceoil absorption. Therefore, the objective of the present study was todetermine the effect of two edible coatings (guar or xanthan gum)or a combination of an edible coating and an increase in the oil cen-trifugation speed during vacuum frying on the quality and oilabsorption of banana chips.

2. Materials and methods

2.1. Materials

Ripe bananas (cultivar Kluai Hom Thong) were purchased froma local market in Thailand. Guar and xanthan gum were purchasedfrom Lab Valley Limited Partnership (Bangkok, Thailand). Palm oilwas supplied by the Patum Vegetable Oil Co., Ltd. (Bangkok,Thailand). Sucrose (Mitr Phol Sugar Group, Bangkok, Thailand)was purchased from a local market.

2.2. Hydrocolloid preparation

An aqueous solution of each hydrocolloid (guar or xanthangum) at 1.5% (w/w) was selected as an appropriate formulationfor the coating application. The solution was heated at 90 �C for30 min before cooling at room temperature.

2.3. Sample preparation and frying conditions

Bananas were washed, peeled, cut into slices (0.3–0.4 cm thick-ness) and immersed in a dilute sucrose solution (0.5% w/w) for15 min according to the commercial process. Banana slices were

washed, drained and weighed before the frying and coating appli-cation. Before frying, banana slices were coated by dipping theminto the hydrocolloid coating solution for 10 min at a ratio of bana-na slices to coating solution of 15:1. A colander was used to pick upthe coated slices and they were allowed to drip for 30 s. The weightof coating solution before and after dipping the slices was recordedto determine the weight gain. Both coated and uncoated bananaslices were used to test the frying conditions. A vacuum fryerequipped with a centrifuge that had all been made at the Depart-ment of Food Engineering was used in this experiment and isshown in Fig. 1. A batch of 10 kg of banana slices was placed inthe vessel and fried in 60 L of palm oil under vacuum (2.66 kPa)at 89 C for 90 min. The vacuum fry temperature was controlledduring the process and was constant, to remove any effect of fryingtemperature on oil absorption. After vacuum frying, the fried bana-na chips were centrifuged at two different speeds—either 140 rpm(normal speed used in vacuum frying) or 280 rpm (speed adjustedfrom 140 rpm to 280 rpm using an inverter) for 5 min to removethe frying oil. This post-frying centrifuge step was tested to studyits efficiency in the vacuum-frying process. Then, the excess fryingoil on the samples was removed under atmospheric pressure at800 rpm for 4 min. Finally, a sample of 250 g of fried banana chipswas packed in each aluminum foil bag and flushed with nitrogengas to prolong the shelf life of the product, sealed and kept at roomtemperature (27 �C) prior to assessment.

The treatments studied in this work were: (1) frying conditionsat a normal centrifugation speed (140 rpm) as the control; (2) sam-ples coated with xanthan gum; (3) samples coated with guar gum;(4) frying conditions at a higher centrifugation speed (280 rpm) asa high speed test without any coating treatment; and (5) samplescoated with guar gum and a high centrifugation speed (280 rpm).

2.4. Weight gain determination

The amount of coating material adhering to the sample duringdipping prior to frying was determined as the difference in weightof the coating solution before and after dipping the banana slices,allowing them to drip between the two measurements. Resultswere expressed as a percentage compared to the initial weight.Three replications were made.

2.5. Lipid content determination

The lipid content of fried banana chips was determined using aSoxtherm Gerhardt rapid Soxhlet extraction system (Model S 306MK S/N 432720). The extraction was performed using the Soxhletmethod with petroleum ether (AOAC, 1975). Three replicationswere made.

2.6. Moisture content and water activity analyses

The moisture content of samples was determined using a Sarto-rius MA-40 moisture meter (Sartorius, Inc., Goettingen, Germany).The water activity (aW) was determined using an AquaLab ModelCX3TE water activity meter (Decagon Devices, Inc., Pullman, WA)at 25 ± 1 �C. Three replications were made.

2.7. Colorimetric measurements of fried banana chips

Fried banana chip color was measured with a Minolta colorim-eter (Model CR-400, Ramsey, NY, USA) using the CIELAB colorparameters, L⁄, a⁄ and b⁄. A standard white calibration plate wasemployed to calibrate the equipment. The color parameters werea D65 light source, 10� standard observer, 45�/0� geometry witha 50 mm diameter measuring area. Three replications were used.The total color difference (DE⁄) was calculated from Eq. (1) in

Motor

Vacuum Pump

Vacuum chamber

Inverter andTemperaturecontroller

Oil receiver tank

Filter

Cooling tower

Basket

Fig. 1. Schematic of the vacuum frying system.

R. Sothornvit / Journal of Food Engineering 107 (2011) 319–325 321

which the color of the fried banana chip without coating (control)was used as the reference point:

DE� ¼ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiðDL�Þ2 þ ðDa�Þ2 þ ðDb�Þ2

qð1Þ

72

74

76

78

80

82

84

86

Xanthan gum Guar gumCoating material

Wei

ght g

ain

(%)

a

b

Fig. 2. Effect of coating material on weight gain of banana chips. Error bar showsstandard deviation. Different letters above graph bars indicate that the averages aredifferent at the 0.05 level of significance.

2.8. Texture analysis

The maximum force or hardness of samples was measuredusing an Instron universal testing machine (model 5569, InstronCorp., Canton, MA) with a 50 N load cell. Samples were puncturedwith a cylindrical plunger (8 mm diameter) and the crossheadspeed was set to 5 mm/min. The hardness of fried banana chipswas defined as the force at maximum compression during first bite(Steffe, 1996) and determined from the force–deformation curves.Three replications were used.

2.9. Sensory evaluation of fried banana chips

Forty untrained panelists were selected to evaluate the fried ba-nana chip quality based on color, flavor, crispness, oil content andoverall quality. These quality attributes were rated using a 5-pointscale, where 5 represented very good and 1 represented bad. Eachsample was randomly numbered and presented to the panelistswith a three-digit number for identification. Spring water was pro-vided between samples for mouth rinsing by each panelist.

2.10. Statistical analysis

A completely randomized experimental design was used tostudy the type of hydrocolloid, the oil centrifuge speed and thecombination of coating solution and speed factors. Three replica-tions were used to determine each property. The software package

SPSS 11.0 for Windows (SPSS Inc., Chicago, IL) was utilized to cal-culate analysis of variance (ANOVA). Duncan’s multiple range testwas used to determine the significant differences between treat-ments at the 95% confidence interval.

3. Results and discussion

3.1. Weight gain of fried banana chips

Dipping banana slices in guar gum solution resulted in signifi-cantly higher weight gain than dipping in xanthan gum, as shownin Fig. 2. This was due to the higher viscosity of guar gum comparedto xanthan gum (Casas et al., 2000). Other studies have reported thatas viscosity increases, the swelling power and solubility index of thesolutions increases (Chaisawang and Suphantharika, 2005; Anna-pure et al., 1999). This might have resulted in better adherence ofthe guar gum coating to the surface of the banana slices.

322 R. Sothornvit / Journal of Food Engineering 107 (2011) 319–325

3.2. Oil absorption of fried banana chips

Fig. 3 shows the oil content of the banana chips for the differenttreatments. Coating the banana slices with each hydrocolloid pro-duced a significant reduction in oil absorption, as reflected by thereduction in oil content compared to the control treatment. Guargum produced a greater reduction of oil absorption (25.22%) in ba-nana chips than xanthan gum (17.22%). This might have been dueto the higher viscosity, which resulted in a higher weight gain ofthe guar gum coating in the banana chips compared to the xanthangum (Fig. 2). Therefore, guar gum was selected as the coating to beapplied in the vacuum frying process with high speed centrifuga-tion in the oil separation process.

The mechanism of oil absorption occurs during the coolingphase and is known as the vacuum effect (Shyu and Hwang,2001; Dana and Saguy, 2006). After the food has been fried com-pletely and removed from the fryer, the product begins to cooland water vapor condenses, with a consequent decrease in internalpressure (Shyu and Hwang, 2001; Dana and Saguy, 2006). The oilthat has adhered on the food surface is then sucked into the voidsof the food. Thus, the oil absorption is a surface phenomenon,which is related to the equilibrium between the adhesion anddrainage of oil as the food is removed from the oil bath (Danaand Saguy, 2006). Therefore, according to the above mechanism,it is hypothesized that the higher the speed of oil centrifugation,the lower the oil absorption of the product. In the present work,application of high speed in the centrifuge process reduced theoil absorption by 17.31% compared with control samples. Thisreduction was similar to that obtained by the application of thexanthan gum coating (17.22%).

Even though the higher speed for oil centrifugation in the vac-uum frying process reduced the oil absorption of the banana chips,it did not provide any significant improvement compared to theuse of the guar gum coating alone or the combination of the guargum coating and the high speed process, which reached an oilabsorption reduction of 33.71%. This indicated that the guar gumcould substitute for the application of the high speed process inthe production of banana chips. Probably, the oil was trapped in-side the voids of the banana slices, making it difficult to be totallycentrifuged out of the fried product, even at high speed. However,the application of a coating could help to fill up or cover the surfaceof the banana slice and thus prevent oil absorption into the product

0

2

4

6

8

10

12

14

Control Xanthan gum Guar gum

Frying condit

Moi

stur

e co

nten

t or O

il ab

sorp

tion

(%)

ab

d

b

c

c

a

a

a

Fig. 3. Effect of frying conditions on moisture content, oil content and water activity (aW

bars indicate that the averages for each parameter are different at the 0.05 level of sign

and the excess oil on the surface of fried product could then be re-moved with a higher centrifugation speed.

3.3. Moisture content and water activity of fried banana chips

There were significant differences in the moisture contentbetween the banana chips coated with the different gums (Fig. 3).Banana chips coated with guar gum had a higher moisture content(5.93%) than those coated with xanthan gum (4.43%). This may berelated to the higher weight gain observed in samples coated withguar gum as a consequence of its high swelling power and solubilityindex at high viscosity (Chaisawang and Suphantharika, 2005). A re-ciprocal relationship between moisture loss and oil absorption hasbeen reported in deep-fat-fried carrot slices coated with gums (Akd-eniz et al., 2006). Gum coatings provided effective moisture reten-tion of the carrot slices due to a strong interaction of hydrogenbonds between water molecules, resulting in lower oil absorptionof the deep-fat-fried samples (Akdeniz et al., 2006). In the presentwork, all banana chips had low aW values (approximately 0.25),which is a good indicator of the potential of vacuum frying to main-tain quality and prolong the shelf life of the product (Fig. 3). It wasalso observed that the lower oil content correlated with the highermoisture content in banana chips, since oil absorption happens asmoisture is removed from the food during the frying process (Saguyand Pinthus, 1995; Mellema, 2003; Salvador et al., 2008).

3.4. Color of fried banana chips

In general, color provides a useful measurement for determin-ing changes due to processing and possible acceptability by con-sumers. In the present work, the application of the coatings orthe increase in the centrifugation speed, or both, increased the L⁄

value of the banana chips compared to the control treatment(Fig. 4). In addition, the edible coatings slightly enhanced the yel-lowness of banana chips, which was reflected in higher b⁄ values(blue to yellow). However, Garcia et al. (2002) reported no signifi-cant changes in the color of potato chips due to the application ofan edible coating, which might be related to the nature of the prod-uct or differences in the frying process. When comparing coatingapplications or high speed centrifugation, or both, there were nosignificant differences in the color parameters (L⁄, a⁄ and b⁄) ofthe banana chips. In the present work, this was also observed in

High speed Guar gum + highspeedions

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35Moisture content Oil absorption Water activity

b

b

c

c

a

aa

Water activity Oil absorption

Moisture content

a W

) of banana chips. Error bar shows standard deviation. Different letters above graphificance.

68

70

72

74

76

78

80

82

Control Xanthan gum Guar gum High speed Guar gum +

high speed

Frying conditions

L* v

alue

-1.6

-1.4

-1.2

-1

-0.8

-0.6

-0.4

-0.2

0Control

Xanthan

gum Guar gum High speed

Guar gum

+ high

speed

Frying conditions

a* v

alue

0

5

10

15

20

25

30

35

40

45

50

Control Xanthan

gum

Guar gum High speed Guar gum

+ high

speedFrying conditions

b* v

alue

0

2

4

6

8

10

12

14

Xanthan gum Guar gum High speed Guar gum +high speed

Frying conditions

ΔE* v

alue

(A) (B)

(C) (D)

Fig. 4. Effect of frying conditions on (A) L⁄; (B) a⁄; (C) b⁄; and (D) DE⁄ color values of banana chips. Error bar shows standard deviation.

R. Sothornvit / Journal of Food Engineering 107 (2011) 319–325 323

the DE⁄ values of the color of the different frying treatments stud-ied and the control treatment, where no differences were found.

3.5. Texture of fried banana chips

Crispness is another important quality factor of most fried foodproducts. Several texture changes occurred when moisture wasremoved from the banana chips. The typical compression load-dis-tance curves of banana chips obtained for the different treatmentsstudied in the present work are shown in Fig. 5. At the beginning,the compression force increased linearly as the compression in-creased until the first set of cells fractured. The presence of air cells

0

10

20

30

40

50

60

0 0.2 0.4 0.6 0.8 1Compression distance (mm)

Com

pres

sion

load

(N)

Control

Guar gum

Xanthan gum

High speed

Guar gum+high speed

Fig. 5. Typical compression curves (load versus distance) of banana chips underdifferent frying conditions.

in the crispy chip structure dropped the force after each fracture.However, the compression force continued increasing as the chipswere compressed until the next set of cells fractured, which endedin a drop in the force. This pattern is called a jagged force–deforma-tion (Peleg and Normand, 1995; Dogan and Kokini, 2007). In thepresent work, different patterns of the jagged force–deformationwere observed depending on the frying conditions (Fig. 5). Coatedbanana chips showed a higher breaking force than the control orthe high speed samples, indicating that the gums provided protec-tion against mechanical damage. Such protection against mechani-cal damage of food has been observed in many films and coatingsincluding banana and mango films (Sothornvit and Pitak, 2007;Sothornvit and Rodsamran, 2008).

The breaking force or hardness is an indicator of the extent ofcrispness. A lower hardness value corresponds with a higher crisp-ness. Therefore, the results showed that the use of the higher speedduring oil centrifugation produced the highest crispness value forthe banana chips, which was similar to the control (Table 1). Con-versely, coating banana slices with the gums produced the lowestcrispness. The banana chips coated with guar gum possessed thehighest hardness or least crispness compared with the other

Table 1Effect of frying conditions on hardness of banana chips.

Frying condition Hardness (N)

Control 31.14 ± 6.85ab

Xanthan gum 40.85 ± 2.24b

Guar gum 52.33 ± 12.54c

High speed centrifugation 27.32 ± 8.49a

Guar gum ± high speed centrifugation 39.58 ± 6.60b

Different superscript letters indicate that the averages are different at the 0.05 levelof significance.

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

Control Xanthan gum Guar gum High speed Guar gum +high speed

Frying conditions

Col

or

0

0.51

1.52

2.5

33.5

44.5

5

Control Xanthan gum Guar gum High speed Guar gum +high speed

Frying conditions

Flav

or

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

Control Xanthan gum Guar gum High speed Guar gum +high speed

Frying conditions

Cris

pnes

s

0

1

2

3

4

5

6

Control Xanthan gum Guar gum High speed Guar gum +high speed

Frying conditions

Oil

cont

ent

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

Control Xanthan gum Guar gum High speed Guar gum +high speed

Frying conditions

Ove

rall

qual

ity

(A) (B)

(C) (D)

(E)

Fig. 6. Effect of frying conditions on sensory attributes (A) color; (B) flavor; (C) crispness; (D) oil content and (E) overall quality of banana chips. Error bar shows standarddeviation.

324 R. Sothornvit / Journal of Food Engineering 107 (2011) 319–325

samples. The higher crispness of the control samples might havebeen due to cell rupture and degradation of pectic substances inthe banana structure during frying, resulting in a weakening ofthe cell walls (Singthong and Thongkaew, 2009). Unlike the un-coated samples, coated samples formed a rigid, resistant film onthe surface of the banana slices that protected the structure duringfrying (Chang et al., 1993; Khalil, 1999; Singthong and Thongkaew,2009). Similar results were found for deep-fat-fried banana chipscoated with alginate, carboxymethyl cellulose and pectin that hadlower crispness compared with control samples (Singthong andThongkaew, 2009).

3.6. Sensory evaluation of fried banana chips

Banana chips coated with the edible coatings or subjected tohigher speed during oil centrifugation were evaluated in a similarway to the control samples for all sensory attributes (Fig. 6). Thepanelists could not detect any reduction of oil absorption resulting

from using the edible coatings, as shown by the instrumental re-sults. Neither were the differences in crispness through texturemeasurements detected by the judges. The visual observation ofthe color in the sensory evaluation showed no differences amongtreatments, indicating that the small differences found in the L⁄

and b⁄ values in the coated banana chips compared to the controlcould not be detected by the judges. The flavor and overall qualityof all the samples were above the limit of acceptability, with no dif-ferences due to coating application. In general, the coatings applieddid not reduce consumer acceptability of the banana chips.

4. Conclusion

The results confirmed that the use of both hydrocolloids (guarand xanthan gum) helped in reducing the oil absorption of vac-uum-fried banana chips. Similarly, the application of a higher speedin the oil centrifugation process in the vacuum fryer also reduced theoil absorption of the banana chips. Guar gum was more effective

R. Sothornvit / Journal of Food Engineering 107 (2011) 319–325 325

than xanthan gum in reducing oil absorption. The oil absorption hada reciprocal relationship with the moisture content retained in thebanana chips. Using the gums as edible coatings had a more pro-nounced reduction in oil absorption than increasing the speed inthe oil centrifugation process, but the differences were not perceivedby the sensory panel. The results showed that both edible coatingsand the modification of the oil centrifugation speed produced signif-icant and substantial reductions in the oil absorption without affect-ing the sensory perceptions, while maintaining the high quality ofthe fried products. Reduction of oil absorption in fried productswould benefit both food industries and consumers, adding valueto the snack market as a healthy food product.

Acknowledgements

The author thanks the Industrial and Research Projects forUndergraduate Students (IRPUS project number I24913008) underthe Thailand Research Fund (TRF) for financial support throughoutthis research and the students, Ms. Jiraporn Wongsuwan and Ms.Chayanee Laosuksuwan for their assistance.

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