Carotenoid Content and Physicochemical and Sensory Characteristics of Carrot Chips Deep- Fried in Different Oils at Several Temperatures A

JFS: Food Chemistry and Toxicology

Carotenoid Content and Physicochemical and Sensory Characteristics of Carrot Chips Deep- Fried in Different Oils at Several Temperatures A. SULAEMAN, L. KEELER, D.W. GIRAUD, S.L. TAYLOR, R.L. WEHLING, AND J.A. DRISKELL

ABSTRACT: The influence of deep-frying using different oils and temperatures on carotenoid content and physicochemical and sensory characteristics of carrot chips was investigated. Sliced carrots were steam-blanched, cooled, soaked in 0.2% sodium metabisulfite, and deep-fried in canola, palm, or partially hydrogenated soybean oil (PHSO) at 165, 175, or 185 ЊC. Frying temperature, but not oil, significantly (P Ͻ 0.05) affected the ␣-carotene, ␤-carotene, and total carotenoid contents. Oil type significantly (P Ͻ 0.05) influenced all color values. Increasing temperature lowered the redness value, which correlated with decreased carotenoid content, color darkening, and decreased hardness value. Trained panelists detected no differences among oil types in crispness, sweetness, odor, and acceptability. The best carrot-chip product was that fried in PHSO at 165 ЊC. Food Chemistry and Toxicology Key Words: deep-frying, carotenoid, carrot chips, oil, frying temperature

Introduction and the type of carotenoids, nutritional 1994, 1995; Baardseth and others 1995, AROTENOIDS ARE IMPORTANT MICRO- status, the presence of antioxidants and 1996; Skrede and others 1997) have de- Cnutrients for human health (Cas- fibers, and the extent of processing veloped carrot chips from carrot slices, tenmiller and West 1998). The biological (Castenmiller and West 1998; Rock and using lactic-acid fermentation to de- function of carotenoids is primarily as others 1998; Riedl and others 1999). crease reducing sugars, and deep-frying vitamin-A precursors (Institute of Med- Carrots, the most important source in palm oil. It has been reported that icine 2000). In addition to their provita- of dietary carotenoids in western coun- the carotenoid levels of carrots were min-A activity, carotenoids may have tries including the United States (Block well retained during the processing of several other important biological func- 1994; Törrönen and others 1996), con- carrot chips (Skrede and others 1997). tions in animals and man (Van Vliet tain the highest amount of ␤-carotene In addition, due to deep-frying, the 1996). Epidemiological studies have of the common fruits and vegetables product contains lipids that may fur- shown that high intakes of carotenoid- (Desobry and others 1998). ␤-carotene ther improve the ability of carrot chips rich vegetables and fruits and high constitutes 60% to 80% of the caro- to serve as a source of provitamin A for blood levels of ␤-carotene are associat- tenoids in carrots, followed by ␣-caro- humans. Nevertheless, research on car- ed with decreased incidence of some tene (10% to 40%), lutein (1% to 5%), rot-chip production without lactic-acid cancers (Törrönen and others 1996), and the other minor carotenoids (0.1% fermentation using different oils and age-related macular degeneration, cata- to 1.0%) (Chen and others 1995). temperatures has not yet been report- racts, coronary heart disease or cardio- Among the provitamin-A carotenoids, ed. vascular disease, and perhaps other dis- ␤-carotene showed the highest vitamin- Our objective was to evaluate the ef- eases and pathological processes A activity on a molar basis (Van Vliet fect of deep-frying on carotenoid con- (Kohlmeier and Hasting 1995; Biesalski 1996; Biesalski 1997). Other carotenoids tent and physicochemical and sensory and others 1997; Kritchevsky 1999). Low are estimated to have only half of ␤- characteristics of carrot chips fried in concentrations of dietary carotenoids carotene’s potency (Castenmiller and different frying oils (canola, palm, may also be needed to inhibit oxidative West 1998). Processing may convert PHSO) at different temperatures (165, damage and decrease oxidation suscep- some of these carotenoids into cis-iso- 175, 185 ЊC) without fermentation prior tibility (Jacob and Burri 1996). mers (Lessin and others 1997) and ep- to deep-frying. Carotenoids are widely distributed oxy-carotenoids (Ball 1998) that may among colored fruits and vegetables have lower vitamin-A activities Materials and Methods and are important sources of vitamin A, (Johnson and others 1996; Ball 1998). especially in those parts of the world To maximize the use of carrots as a Materials where the intake of animal foods is rela- source of provitamin A as well as an an- Fresh jumbo carrots (Daucus carota tively low (Van Vliet and others 1996; tioxidant, it is important to find an ap- cv. Navajo) harvested in Bakersfield, West 1998). However, the bioavailability propriate processing method to manu- Calif., U.S.A., were purchased from of the provitamin-A carotenoids from facture products that are not just highly Grimmway Farms (Bakersfield, Calif., plants is greatly influenced by many preferred by consumers but also are U.S.A.) and arrived packaged in linear factors such as the structure of the car- good nutritional sources of provitamin low-density polyethylene bags (2.54 mil; otenoids, the nature of the embedding A. In recent years, researchers (Slinde Mercury Plastics, Inc., Industry, Calif., matrix, levels of dietary fat, the amount and others 1993; Aukrust and others U.S.A.). The roots were stored in these

© 2001 Institute of Food Technologists Vol. 66, No. 9, 2001—JOURNAL OF FOOD SCIENCE 1257 ® C C C 18 Њ Њ Њ C until at 23 Њ m parti- at 38 at 38 g at 5 2 2 ␮ Ϫ ϫ Ϫ 50 m Ϫ 4.6 mm i.d.) m (5- C) overnight. 1 column (Rai- Њ 1 Ϫ ϫ 18 18 Ϫ 50 Ϫ C). On the 3rd day, the day, C). On the 3rd Њ C and 90% RH according C and 90% Њ 50 4.6 mm) C Ϫ ϫ 0.000054 g s 0.000054 0.000 358 ml s 0.000 358 Ͻ Ͻ at 38

2 2 Ϫ m, 250 m The HPLC system consisted of the The HPLC system The extraction of carotenoids was ␮ 1 Ϫ (MVTR) (MVTR) following Waters Waters Associates, following Inc. (Mil- equipment: a 600E ford, Mass., U.S.A.) deliverysolvent system, a U6K injector, and a 5200 printer- 484 UV detector, was carried out The separation plotter. Microsorb-MV using a reversed-phase (5 U.S.A.), which was Mass., Woburn, nin, protected with a guard column of C cle size). carried out using the modified method of Barua and Olson (1998) as follows: Carrot chips or fresh carrots (30 g) were crushed or pureed using a food HC Model & Decker, (Black processor g 3000, Shelton, Conn., U.S.A.) and 2 was weighed into a 20-mL vial. Three mL of THF was added to the vial, which Teflon-coated a with was then covered cap, and vortexed for 1 min. The mixture was homogenized (Biohomogeniz- er M133/1281-0, Biospec Products Inc., Bartlesville, Okla., U.S.A.) at low speed for 1 min and at high speed for 3 min. During the homogenization, the vial was immersed in ice, and light exposure was limited. The homogenizer was rinsed with THF (1 to 2 mL), more THF was added into the mixture until the volume reached 10 mL, and the vial contents were vortexed again for 1 min and then flushed with argon gas for 3 was extract The the air. min to remove kept in the freezer ( were O carotenoids HPLC analyses of materials (3 cm length packed with spheri-5-C to the manufacturer. The packaged to the manufacturer. were stored at products and 90% RH, while those of Curlon RH, while those of and 90% physicochemical, used for carotenoid, and sensory analyses. The next day, the vial contents were The next day, vortexed for 1 min and put back into ( the freezer and 0% RH, and MVTR < 0.0000896 g and MVTR < 0.0000896 and 0% RH, s vial contents were vortexed again for 1 min and centrifuged at 3000 for 10 min. The supernatant fluid was collected into a 100-mL brown volu- metric flask (or 50 mL depending upon the carotenoid content) by decantation. A 2nd extraction was done on the residue using 4 mL THF followed by centrifugation as described. A 3rd and 4th extraction with 4 mL THF followed by centrifugation was performed as described when needed to produce a white plant residue without any re- . ® C). Њ 0.00018 to 0.00014 C and 0% RH and Њ Grade 9301-S) (Cur- film (2.5-mil thick) Ͻ

® ® 2 film (5.0-mil thick) was at 23 ® 2 Grade 2500-G) and plain Ϫ were O ® sealant, and nylon structural ® m ® 1 Ϫ moisture vapor transmission rate The Curlon formable (Curlon wood Bemis Specialty Films, Oshkosh, Wis., U.S.A.)—were used for packaging the chips using this machine, with the nonformable film being on the top ex- terior layer and the formable being be- The Curlam low. polyviny- was constructed of polyester, lidine chloride, adhesive, and Surlyn layers. The barrier properties of Curlam The carrot slices were fried (0.45 kg per batch) for 3 to 5 min or until there were no visible bubbles due to residual water (Aukrust and others 1995). The fried carrot chips were drained on paper a towels and shaken with flaked salt to salt content of 1.0% (w/w) (Melton and others 1993). Each treatment was repli- cated 2 times. The resulting carrot chips were weighed, and the total yield of carrot chips (%) was calculated as per- centage of weight of fresh sliced carrots before and after deep-frying. The carrot chips were then packed and flushed with nitrogen gas using a Multivac M855 U.S.A.). Mo., City, Kansas Inc., (Multivac kinds of film—plain nonformable Two (Curlam of carrot peeling, the length and the length and the peeling, of carrot duration of carrot slices, the thickness concen- and cooling, the of blanching solution sodium metabisulfite tration of and the of soaking, and the duration of and the duration frying temperature study, frying. on this preliminary Based and cut into 55- carrots were trimmed peeled mm lengths and mechanically Machine (Hobart using a Hobart Peeler U.S.A.) Ohio, Troy, Co., Manufacturing for 1 min and sliced at the lowest speed using a Dito to a 1.5-mm thickness TR-22 (Dean Food Dean Slicer Model Calif., U.S.A.). Preparation, Los Angeles, were then steamed The carrot slices cooled under run- blanched for 4 min, min, and soaked in ning tap water for 4 0.2% (w/v) solu- sodium metabisulfite tion for 15 min (6 L for 2.75-kg carrot slices). Sulfite has been reported to function as an antioxidant in stabilizing carotenoids in dehydrated carrots (Zhao and Chang 1995). The soaked carrot slices were drained until the surface a was nearly dry and then deep-fried in 1427 (Elgin, Model Fryer Toastmaster Ill., U.S.A.) using 3 types of oils (canola, palm, and PHSO) and 3 different frying temperatures (165, 175, and 185 constructed of proprietary coextruded film with ethylene vinyl alcohol barrier, Surlyn ml s - - - ␣ ␣ ␣ —Vol. 66, No. 9, 2001 66, No. —Vol. m 250 ␮ g/g re- ␮ -carotene ␤ -cryptoxan- IP 3 ␤ 18 and dissolved in 2 -carotene as well g/g canola oil, and ␣ ␮ -carotene was isolated and -carotene was purchased ␣ ␤ -carotene; however the -carotene; however -carotene from fresh carrots fresh -carotene from ␤ ␣ m membrane filter (Pall Gelman JOURNAL OF FOOD SCIENCE g/g PHSO. ␮ ␮ All-trans- The production of deep-fried carrot 3.2-mm column (Phenomenex, Tor- 3.2-mm column (Phenomenex, C (Suslow and others 1998) and 98% and others 1998) C (Suslow from Sigma (St. Louis, Mo., U.S.A.); lutein from Sigma (St. Louis, was purchased from Fluka (Ronkonko- U.S.A.); all-trans- ma, N.Y., 0.21 chips was conducted at the Univ. of Ne- chips was conducted at the Univ. braska Food Processing Center Pilot Plant. A preliminary study was conducted to determine the required speed of the peeler machine and the duration rance, Calif., U.S.A.) and a mixture of acetonitrile:tetrahydrofuran (THF):methanol:1% ammonium acetate (65:25:6:4) as the mobile phase. The ϫ carotene peak identified utilizing the re- (1982) and Wilson and ports of Bushway Chandler and Schwartz (1987) was collected and dried using N 1258 Laboratory, Ann Arbor, Mich., U.S.A.) Mich., Ann Arbor, Laboratory, prior to use. Carrot-chip production carotene from this carrot extract was estimated to be 96%. All HPLC-grade sol- methanol, and THF, (acetonitrile, vents hexane) were obtained from Fisher Sci- The Lawn, N.J., U.S.A.). (Fair Co. entific HPLC-grade solvents were degassed under vacuum and filtered through a 0.45- as other carotenoid working standards were confirmed spectrophotometrically (Beckman DU 640, Beckman Instruments Inc., Fullerton, Calif., U.S.A.) using previ- ously reported absorptivities (Epler and others 1993). The purity of crystalline HPLC-grade hexane. The identities and concentrations of the purified from fresh carrots in our labora- The tory. was extracted according to Bushway and Wilson (1982) then isolated by repeated a injection into a HPLC instrument with Phenomenex Ultramex 3 C relative humidity (RH) for 1 to 2 mo (RH) for relative humidity tempera- At these prior to processing. roots can RH, mature carrot tures and for 7 to 9 mo (Hardenburg be stored were 1990). The oils utilized and others & Clark Holme oil (Welch, palm refined N.J., U.S.A.), canola Co., Inc., Newark, Cincinnati, Ohio, oil (Procter & Gamble, (Bunge Food, Brad- U.S.A.), and PHSO These oils did not con- U.S.A.). Ill., ley, of tain detectable quantities and cis-9- thin was purchased from Indofine Chem- ical Co., Inc. (Belle Mead, N.J., U.S.A.); and all-trans- polyethylene bags in the dark at 0 to 2 dark at in the bags polyethylene Њ carotene content was 0.075 carotene content fined palm oil, 0.36 Carotenoid Content of Carrot Chips . . . Chips Carrot of Content Carotenoid

Food Chemistry and Toxicology Carotenoid Content of Carrot Chips . . . maining orange color. The THF extract CIE color system, “L” describes light- ented test (Watts and others 1989). Car- was pooled in the above flask and then ness (black ϭ 0, white ϭ 100); “a” inten- rot chips were removed from the freez- was topped off with a mixture of aceto- sity in red (a Ͼ 0); “b” intensity in yellow er 18 h before testing (Melton and oth- nitrile, THF, methanol, and 1% ammo- (b Ͼ 0); and “hue angle” (HueЊ ϭ tan-1 ers 1993), and the chips were at room nium acetate (65:25:6:4). Before inject- b/a) the hue of the color (red ϭ 0, yel- temperature when tested. Each panelist ing into the HPLC system, the extract low ϭ 90). The color analyses were per- received coded samples. Testing was was diluted with mobile phase 10 to 100 formed on homogenized raw carrots conducted in individual booths times. The carotenoids were separated and on crushed carrots chips (Slinde equipped with white fluorescent lights. using acetonitrile:THF:methanol:1% and others 1993). The panelists came to the sensory labo- ammonium acetate (65:25:6:4) as the Texture. The texture of carrot chips ratory on 4 different occasions, and for mobile phase under isocratic condi- was measured using a TAXT2 Texture each occasion, each panelist judged 6 tions (Nierenberg and Nann 1992; Sun Analyzer (Texture Technologies Corp., samples from the 9 treatments utilizing and others 1997). Injections (50 ␮L) Scarsdale, N.Y., U.S.A.). This method a Balanced Incomplete Block Design. were made in duplicate for each sam- measured the force needed to break a ple. Proofs of identities and pre-extrac- chip at a constant speed. The force and Statistical analyses tion spiking were conducted. Percent work required to rupture the chips can Carotenoid and physicochemical recoveries of the congeners from pre- be correlated to hardness and crunchi- data were tabulated and analyzed by 2- extraction spiking were 82 to 89 (lutein), ness of the chips. The instrument was way analysis of variance (ANOVA) to 88 to 98 (␣-carotene), and 95 to 100 (␤- equipped with an aluminium guillotine determine the effect of oil, tempera- carotene). or knife blade, 4 cm ϫ 4 cm, 1 mm ture, and oil:temperature interaction. A Individual carotenoids were identi- thick, and an acrylic fixture to hold the 2-way ANOVA with oil:temperature fied by comparison of retention times chip in position (TA-260 Hinge and treatments and judges as sources of and absorbance spectra to those of car- Cantilever Fixture, Texture Technolo- variation was carried out on sensory Food Chemistry and Toxicology otenoid standards and comparison to gies Corp.). Twelve chips from each data to determine differences among previous carotenoid separation on C18 treatment were used for the testing, the treatments (Shamaila and others columns. Separation times using a flow and the results averaged. 1996). Correlations between values rate of 1 mL/min were 3.82 min for Water activity. The water activity of were also determined (Steel and others lutein, 14.35 for ␣-carotene, 15.18 min the carrot chips before and after frying 1997). For all analyses, differences were for ␤-carotene, and 16.24 min for tenta- was determined by an AquaLab water considered significant at P Ͻ 0.05. All tively identified cis-9-␤-carotene. Skre- activity analyzer (Decagon Devices, statistical analyses were carried out de and others (1997) and Sharpless and Inc., Model CX-1, Pullman, Wash., with the General Linear Model (GLM) others (1996) identified this peak as cis- U.S.A.). Samples were crushed and ana- procedure of SAS version 6 (SAS Insti- 9-␤-carotene using donated cis-9-␤- lyzed in duplicate (Wagner and Warthe- tute Inc., Cary, N.C., U.S.A.). carotene standard. The elution order of sen 1995). the tentatively identified cis-9-␤-caro- Moisture and dry-matter content. Results and Discussion tene was the same as reported by Skre- For moisture content and dry-matter de and others (1997), Sharpless and oth- determination of fresh carrots and car- Carotenoid content of fresh and ers (1996), and Sander and others (1994) rot chips, the samples were crushed, blanched carrot slices who utilized donated cis-9-␤-carotene and portions of 2 g weighed, dried at The carotenoid contents of fresh and standards. Other researchers (Nyam- 105 ЊC for 20 to 22 h, cooled in a desic- blanched carrot slices are presented in baka and Ryley 1996; Chen and Chen cator, and weighed again (Baardseth Table 1. Carotenoid concentrations of 1994; Craft and others 1990) also identi- and others 1995). fresh carrots used in this study were fied cis-9-␤-carotene from various food Fat content. Fat content of fresh higher than those reported by Skrede products in a manner similar to that carrots and carrot chips was deter- and others (1997) for carrot chips pre- utilized in the present research. As no mined according to AOAC International pared using lactic-acid fermentation cis standards were commercially avail- official method no. 960.39 (AOAC Inter- prior to the frying. Heinonen (1990) re- able, cis-9-␤-carotene was quantified national 2000) using a Soxtec System ported the carotenoid concentrations using the all-trans ␤-carotene standard HT6 (Tecator Soxtec System, Tecator of 19 cultivars of carrots: (␮g/100 g w/ (Chen and others 1995; Lessin and oth- Inc., Herndon, Va., U.S.A.) instrument. w) ␣-carotene ranged from 2200 to ers 1997). Vitamin-A activity was calcu- 4900; ␤-carotene, from 4600 to 10300; lated as retinol activity equivalents Sensory analyses and lutein, from 110 to 560. The carrots (RAE) using 12 ␮g per RAE for all-trans The sensory portion of this research used in our study contained caro- ␤-carotene and 24 ␮g per RAE for all- was approved by the university’s Insti- tenoids in these reported ranges. After trans ␣-carotene (Institute of Medicine tutional Review Board for Research In- blanching, no significant (P Ն 0.05) 2001). The retention values (%) of caro- volving Human Subjects. Fourteen po- changes in the carotenoid content were tenoids in the carrot chips as the effect tential panelists, all Americans from the observed. However, based on the dry- of carrot-chip processing were calcu- Plains area, age 19 to 49 y, were recruit- weight basis, the carotenoid concentra- lated as described by Murphy and oth- ed from faculty, staff, and graduate stu- tions were increased in the blanched ers (1975). dents at the Univ. of Nebraska, Lincoln carrot. This can be understood as to evaluate the color, crispness, odor, blanching may cause the denaturation Physicochemical analyses sweetness, flavor, and overall accept- of the carotene-binding protein, which Color. A Minolta CR300 Chromame- ability of these products. The panelists further releases the carotenoids so that ter (Minolta Co., Ramsey, N.J., U.S.A.) were trained and oriented in doing the they can be easily extracted (Dietz and was used to measure L, a, and b values scoring test (Lawless and Heymann Erdman 1989). Blanching produces a of fresh carrots and carrot chips. In the 1998) employed for this product-ori- gradual breakdown in the protoplasmic

Vol. 66, No. 9, 2001—JOURNAL OF FOOD SCIENCE 1259 Ͻ

a P - and bcd bc bc cde b e b e de -caro- ␣ ␣ 3669 3175 3683 3721 2866 3746 3277 3038 activity 3580 Vitamin-A 0.05) in the Ͻ

0.05) the caro- P Ͻ

P c bc b e b e bcd de bcde 68406 59544 72275 70530 51222 72456 61290 54580 65692 Total g/100 g w/w), and vitamin-A ␮ ␮ ␮ ␮ ␮ -carotene, total carotenoids, and - ␤ 0.05) in the retention of bc cd bc bc cd b d bcd ␤ ␤ ␤ ␤ ␤ The frying temperature, but not the The frying temperature, The carotenoid levels of carrots were Ն d

-carotene breakdown during storage -carotene breakdown P ␤ and that sulfite of dehydrated carrots acts as an antioxidant. affected ( type of oil, significantly frying may have contributed to the rela- to the contributed may have frying retention of the carotenoid tively high 3) in the activity (Table and vitamin-A the discussed earlier, As carrot chips. dena- treatment may have blanching and carotene-binding protein tured the carrots, fiber matrix of the softened the release dur- thus increasing carotenoid and Chang (1995) ing extraction. Zhao and cornstarch can reported that sulfite and total retard loss of redness tenoid content and the vitamin activity of the carrot chips. This phenomenon was expected (Hagenimana and others 1998). Several chemical and physical changes occur during frying, including starch gelatinization, protein denaturation, water vaporization, and crust formation (Hagenimana and others mass addition to heat transfer, 1998). In transfer takes place and is character- ized by the movement of oil into the product and movement of water in the form of vapor from the product into the oil (Saguy and Pinthus 1995; Pinthus and others 1993). So, factors like frying temperature, frying duration, and product size and shape influence the carotenoid content of the fried carrot chips. well retained during the processing of study (Table in the current chips carrot 3). There were no significant differences ( 0.05) the carotenoid content of carrot 0.05) the carotenoid temperature sig- chips. Increased frying ( nificantly decreased tene, vitamin-A activity among the chips types of oil. However, fried in different significant differences ( retention of these carotenoids and vita- 14870 12854 17987 15749 9468 17301 13090 10208 13948 g a g/ ␮ ␮ -car- ␤ g RAE/ activity c bc bc b b d b bcd bcd ␮ ␮ ␮ ␮ ␮ Vitamin-A - Cis-9- ␤ ␤ 36655 31659 36529 37000 28958 37156 32728 30564 ␤ 36447 ␤ ␤ -carotene and ␤ 0.05). Total Յ

-carotene, 9468 to P ␤ cd bc bc f cd b d de def - ␤ ␤ ␤ ␤ ␤ - ␣ ␣ 13022 15321 10832 15573 13187 carotene14750 carotene12870 15301 carotene carotenoids ␣ ␣ ␣ g/100 g w/w) lutein, 1964 to g/100 g w/w) lutein, ␮ -carotene. The existence of cis- -carotene. The existence -carotene, 10832 to 15573; -carotene, 10832 to carotene. - ␤ ␣ ␤ -carotene but not -carotene in the deep-fried carrot g The carotenoid contents of deep- The carotenoid contents carotene - Cis-9- ␮ - ␤ ␣

␤ ␤ ␤ ␤ ␤ ␤ ϩ g cis-9- 9- chips was also found by Skrede and others (1997). The total carotenoid and vitamin-A activity of the carrot chips (w/w) ranged from 51222 to 72456 100 g chips and from 2866 to 3746 RAE/100 g chips, respectively. The caro- respectively. RAE/100 g chips, tenoid contents and vitamin-A activities of carrot chips reported in the present study were higher than those reported by Skrede and others (1997), but this may be due to the differences in carrot variety and processing method. The blanching and soaking of the carrot slices in 0.2% sodium metabisulfite before fried carrot chips in the present study fried carrot chips in were: ( 2480; and tentatively otene, 28958 to 37156; identified cis-9- Aukrust and others (1995), also using also (1995), and others Aukrust found the technique, the fermentation 16%, de- between 12.5% and yield to be of the initial concentration pending on fermen- brine used during NaCl in the as well as in varieties tation. Differences may be re- methods in the processing in carrot- sponsible for the differences chip yield. As mentioned earlier, 2). 17987 (Table minute quantities the 3 oils did contain of ␮

ϩ carotene - - —Vol. 66, No. 9, 2001 66, No. —Vol. ␣ ␣ carotene ␣ ␣ ␣ 24 12 g/100 g w/w) and vitamin-A activity ( g/100 g w/w) and vitamin-A activity - ␣ g ␮ ␮ ␮ ␮ ␮ ␣ g ␮ carotene carotene carotene carotenoids ␮

15.916.2 2275 2438 Yield Lutein 24 12 24 (3270) (26224)(4662) (71585) (36128) (98509) (1328) (140627) (101079) (9714) (7058) g RAE/100 g w/w, ␮ 185165175185 16.3 16.5 16.1 16.4 1964 2426 2285 2042 11766 175185175 16.1 16.1 16.1 2131 2161 2480 Frying 88.092.0 394 372 3160 2883 8626 7861 — 106 12180 11222 851 775 g RAE/100 g w/w) of carrot chips ␮ ␮ ␮ ␮ ␮ -carotene in blanched carrots -carotene in blanched JOURNAL OF FOOD SCIENCE g ␤ The yields for carrot chips ranged oil temp °C g Retinol Activity Equivalent (RAE) = g Retinol Activity Equivalent (RAE) = values within a column with the same letters are not significantly different ( Palm 165 PHSO: partially hydrogenated soybean oil ␮ ␮ slice % content Lutein PHSO Canola 165 Fresh from 15.9% to 16.5% (Table 2). The 2). from 15.9% to 16.5% (Table types of oil and frying temperatures did not significantly affect the yields of carrot chips. The yields of carrot chips in our study were higher than reported by Baardseth and others (1995) using lactic-acid fermentation (10.1% to 11.7%). g 1260 a b-f Type of Type Table 2—Effect of type of oil and frying temperature on yield (%), carotenoid content ( content of type of oil and frying on yield (%), carotenoid temperature 2—Effect Table activity ( Blanched Number in ( ) represents amount on dry-weight basis. a 100 g w/w) of fresh and blanched carrot slices 100 g w/w) of fresh and blanched carrot Carrot Moisture Table 1—Carotenoid content ( 1—Carotenoid Table Yield, carotenoid content, and vitamin-A activity of carrot chips Carotenoid Content of Carrot Chips . . . Chips Carrot of Content Carotenoid subsequent with organization, structure release of pressure, the loss of turgor and oth- (Fuchigami pectic substances effect. and a final softening ers 1995), disruption also induces more Blanching and others cells (Prestamo of the carrot also and others (1999) 1998). Howard carrots found that steam-blanched carotenes than contained higher total to the in- fresh carrots. In addition content in the creased carotenoid also result- blanched carrots, blanching of carotenoids ed in isomerization 1998). In the (Desobry and others we tentatively identified study, present cis-9- that did not exist in the fresh carrot. that did not exist of fresh and The vitamin-A activities the present study blanched carrots in and 775 851 were respectively, an amount high enough to respectively, satisfy the human daily need for vitamin A (Institute of Medicine 2001).

Food Chemistry and Toxicology Carotenoid Content of Carrot Chips . . . min-A activity were observed among higher. The L, a, and b values reported primary compositional factor that influ- chips fried at different temperatures, by previous researchers using lactic- ences darkening. with those fried at 185 ЊC having the acid fermentation were : 44.9 to 51.3 The redness (a) value of carrots re- lowest retention. On the average, for all (L), 10.1 to 12.6 (a), 15.8 to 26.5 (b) flects the carotenoids in carrots (Baard- temperatures and oil types, about 85% (Slinde and others 1993); 49.0 to 52.4 seth and others 1995). Our data indicated of the initial carotene content of the (L), 15.1 to 16.3 (a), 26.2 to 29.0 (b) that there were positive correlations be- carrots was retained in the carrot chips, (Baardseth and others 1995) and 15.9 to tween the redness (a) values and the fol- either as all-trans ␣- or ␤-carotene or as 20.4 (b) (Aukrust and others 1995); val- lowing carotenoid contents: lutein cis-9-␤-carotene. ues observed in the current study are (r ϭ 0.77, P Ͻ 0.05), ␣-carotene (r ϭ 0.79, given in Table 4. The purpose of lactic- P Ͻ 0.05), ␤-carotene (r ϭ 0.76, P Ͻ 0.05), Color value, texture, water activity, acid fermentation prior to frying in the cis-9-␤-carotene (r ϭ 0.73, P Ͻ 0.05), total moisture content, and fat content previous studies was to decrease the re- carotenoid (r ϭ 0.77, P Ͻ 0.05), and vita- of carrot chips ducing sugars that are responsible for min-A activity (r ϭ 0.77, P Ͻ 0.05). The The color of the carrots was report- the browning reaction during the frying decrease in a values in the carrot chips ed to be largely due to the presence of of the carrot slices. The blanching treat- fried at the higher temperature correlat- carotenes (Bao and Chang 1994). The ment followed with rinsing the ed with the loss of ␣- and ␤-carotenes orange color of carrots and carrot blanched carrots under running tap wa- (Table 2). Skrede and others (1997) re- chips was described by the lightness (L), ter and then soaking in 0.2% sodium ported a significant correlation (r ϭ redness (a), yellowness (b), and HueЊ metabisulfite may contribute to the de- Ϫ0.72, P Ͻ 0.05) between HueЊ value and parameters. The color values of carrot creased reducing sugars in the carrot the total carotenoid content. However, chips ranged from 32.3 to 46.1 (L), 14.7 slices, or the sulfite may also block the our data indicated no significant correla- to 20.4 (a), 13.4 to 26.5 (b), and 42.1 to formation of pigments in the Maillard tion (P Ն 0.05) between Hue value and 53.5 (HueЊ). Deep-frying seemed to de- reaction pathway, resulting in deep- the total carotenoid content. Food Chemistry and Toxicology crease the L, a, and b values of the fresh fried carrot chips with good color in the Frying temperature and the interac- carrots, while blanching had little effect. present study. Marquez and Anon tion of type of oil and temperature sig- The type of oil significantly influenced (1986) reported that blanching can re- nificantly affected (P Ͻ 0.05) the texture (P Ͻ 0.05) the carrot-chip color in L, a, sult in the removal of sugars and might value (that is, the hardness) of carrot b, and HueЊ values (Table 4). Palm oil be an effective way to control color de- chips in the current study. The type of seemed to produce carrot chips that velopment during frying since the re- oil alone did not affect the hardness of were higher in lightness (L), redness (a), ducing-sugar content is normally the the chips. There was no certain pattern yellowness (b), and HueЊ values than PHSO and canola oil. However, the redness (a) value of carrot chips fried in PHSO was not significantly different (P Table 3—Effect of type of oil and frying temperature on retention of carotenoid and vitamin-A activity in carrot chips (%) Ն 0.05) from those fried in palm oil. Frying temperature also significantly af- Type of Frying ␣- ␤- Total Vitamin-A fected (P Ͻ 0.05) the carrot chip color oil temp °C carotene carotene carotenoids activity in L, a, and b values but not the HueЊ Canola 165 65.6bc 67.2abc 85.9abcd 67.0abc value. Increasing the frying tempera- 175 75.2ab 68.5ab 90.5abc 69.5ab ture significantly decreased (P Ͻ 0.05) 185 65.5bc 58.9bc 78.4bcd 59.9bc ab ab a ab the color attributes of carrot chips in L, Palm 165 78.4 69.1 95.9 70.0 175 78.1ab 69.1ab 93.3ab 70.5ab a, and b. 185 56.6c 54.7c 68.6d 54.9c The color values of carrot chips in PHSOe 165 81.2a 70.9ab 98.3a 72.5a the current study prepared without fer- 175 67.1bc 61.0bc 81.0bcd 62.0abc mentation were similar to chips pro- 185 61.2c 58.3bc 73.7cd 58.6bc duced using lactic-acid fermentation, a-dvalues within a column with the same letters are not significantly different (P Յ 0.05). though the redness (a) values were ePHSO: partially hydrogenated soybean oil

o Table 4—Effect of type of oil and frying temperature on L, a, b, and Hue values, texture, water activity (aw), moisture content, and fat content of carrot chips Carrot Frying Texture Water Moisture Fat slice temp ЊC L a b Hue0 g force activity content % content % Fresh — 45.1 25.5 24.1 43.4 — — 88.0 nd Blanched — 47.2 25.8 25.2 44.3 — — 92.0 nd Fried in Canola 165 33.7ef 17.3b 16.5d 43.6cd 494.3a 0.44a 2.1b 59.2b 175 34.0ef 16.1bc 14.6e 42.1d 437.8ab 0.44a 2.6ab 60.1ab 185 32.3f 14.7c 13.4e 42.4cd 334.5d 0.44a 2.9a 58.8b Fried in Palm 165 46.1a 20.4a 26.5a 52.4a 412.6bc 0.41cde 2.2b 61.2ab 175 42.2b 17.9b 23.3b 52.6a 426.6bc 0.42bc 2.7ab 61.4ab 185 43.2b 17.6b 23.8b 53.5a 457.1ab 0.42b 2.7ab 61.5ab Fried in PHSOg 165 38.3c 19.9a 19.5c 44.4c 429.4bc 0.40e 2.0b 60.6ab 175 36.4d 17.2bc 17.5d 45.5bc 408.6bc 0.40de 2.3ab 62.0a 185 34.6de 15.5c 16.5d 46.9b 390.4bcd 0.41bcd 2.8ab 61.1ab nd = not detectable a-fvalues within a column for fried products with the same letters are not significantly different (P Յ 0.05). gPHSO: partially hydrogenated soybean oil

Vol. 66, No. 9, 2001—JOURNAL OF FOOD SCIENCE 1261 e Ն Ն

f fg fg h h h fg fg fg P P 0.85) 6.1 5.6 5.6 4.7 4.4 4.5 5.6 5.5 5.0 Flavor 0.05) in ϭ Ϫ

d Ն b

P f fg g g fg fg fg fg fg 0.05) and sweet- 0.05) the overall 0.90, r Ͻ 0.05).

4.4 4.0 3.9 4.6 4.4 4.3 4.8 4.6 4.6 Ͻ Ն P

C. There were posi- Њ 0.05) with the overall P Sweetness ϭ Ϫ Ͻ

a P 0.92, c ϭ 0.05) negatively correlated 0.05) negatively g g g g g g fg f fg Ͻ

0.73, 4.4 4.0 4.2 4.3 4.0 4.3 4.5 5.3 4.5 0.85, r Odor P ϭ ϭ Ϫ b The overall acceptabilities of carrot

L acceptability of carrot chips. The higher the score on crispness and sweetness, the higher the acceptability of the carrot chips. Therefore, we can conclude that the crispness and the sweetness of ness (r darker. The lightness (L), redness (a), (L), redness lightness The darker. signifi- (b) values were and yellowness cantly ( (r with the color scores from sensory color scores from with the L, a, which means that higher analyses, with lower were associated and b values colored chips. color scores and lighter difference ( There was no significant overall acceptability among the carrot chips fried in different types of oil. signif- the frying temperature However, icantly affected ( acceptability of the chips, with the highest acceptability scores being for carrot chips fried at 165 tive correlations between the scores of crispness (r 0.05) in crispness scores as an effect of 0.05) in crispness scores by panelists. This oil types observed value dis- agrees with the hardness of the chips 4). All (Table cussed above have similar crisp- were perceived to Although there ness by the panelists. differences ( were no significant 0.05) in the sweetness scores of the 0.05) in the sweetness types of oil and chips fried in different there was a at different temperatures, trend indicating that the increasing temperature seemed to decrease the sweetness score of the chips. chips are given in Figure 1, with 9 being 1 the highest score (like extremely) and the lowest score (dislike extremely). Ba- was ac- product the carrot-chip sically, ceptable to the panelists. There were no significant differences ( fg h h f fg h f g h Ն 6.3 4.3 4.7 6.8 6.0 4.6 6.7 5.5 4.4

P Crispness a ijk l kl jk hij hi f fg gh C Color Њ Њ Њ Њ Њ 175185165175 4.7 185 4.3 4.4 5.5 6.3 175185 5.3 6.0 0.05) by frying tempera- 0.05) affect the flavor. Frying 0.05) affect the flavor. Ͻ

P P m 0.05) the color score of carrot Ͻ The sensory characteristics of carrot

Values within a column with the same letters are not significantly different (P within a column with the same letters are not significantly different Values PHSO: partially hydrogenated soybean oil P 1 = not sweet at all, 9 = very sweet 1 = very bland, 9 = very intense 1 = very light, 9 = very dark 1 = very tough, 9 = very crispy 1 = very bland, 9 = very intense Type Frying of oil temp chips prepared using lactic-acid fer- lactic-acid using prepared chips others Hagenimana and mentation. content of that the oil (1998) reported linearly chips was fried sweet-potato content of the dry-matter related to of the The fat content storage roots. on the is also dependent carrot chips and others variety of carrots (Baardseth content of carrot 1995). The high-fat an advantage or chips could be either view- depending on one’s disadvantage, since point. It could be disadvantageous may contribute to the high-fat content But, the high-fat high-calorie intake. could be an ad- content of carrot chips in developing coun- vantage to people to increase their cal- tries who still need the high-fat Moreover, orie intakes. chips may help in content in the carrot increasing the absorption and utiliza- tion of carotenoids as vitamin-A precursors, which is very important for people in developing countries. Provita- min-A carotenoids are better retained by humans when consumed together with fat (Dimitrov and others 1988; Jalal 1999). Takyi and others 1998; tures. The oil types appeared to significantly ( temperature also significantly affected ( chips are presented in Table 5. There 5. Table in presented chips are were no significant differences ( 0.05) in odor and sweetness of carrot chips fried in different types of oil and the However, temperatures. at different crispness appears to be significantly affected ( d e f-l m Table 5—Effect of type of oil and frying on sensory 5—Effect temperature characteris- Table tics of carrot chips CanolaPalm 165PHSO 5.0 165a b 3.7 c Sensory characteristics chips. With increasing frying increasing tempera- With chips. ture, the color score of the chips was increased, which means the chips were —Vol. 66, No. 9, 2001 66, No. —Vol. 0.05) the Ͻ

) and moisture P w 0.05) between moisture Ͻ

0.05) in the fat content of P Ն

0.05) in water activity in the P Ͻ

JOURNAL OF FOOD SCIENCE P ), showed a strong correlation at –0.74, o The fat content of carrot chips in the The water activity (a ϭ carrot chips among the chips fried in different frying oils and frying temperatures. Similar results were observed by Baardseth and others (1995) on carrot content and the redness (a) value of the chips. The issue of frying temperature is rather complex as temperature influences not only color development (darkening), which influences the carotenoid changes, but also moisture loss, both of which are important in the evaluation of the quality of the fried product (Hansen 1998). current study was high (58.8% to 62.0%) was no significant dif- There 4). (Table ference ( each temperature. There was a significant difference in the relationship between moisture content and color at the different frying temperatures. Our data indicated a negative correlation (r 1262 content of carrot chips in the present content of carrot chips to 0.44% and 2.0% study ranged 0.40% This low- 4), respectively. to 2.9% (Table help the carrot er water activity may content dur- chips maintain carotenoid others (1982) re- ing storage. Arya and were relatively ported that carotenoids activity ranged from stable when water to a moisture 0.32 to 0.57, equivalent content of 8% to 12% in freeze-dried carrots. There was a significant difference ( Carotenoid Content of Carrot Chips . . . Chips Carrot of Content Carotenoid the affected how temperature as to was that the trend however, hardness, the lower the temperature, the higher no signif- That there were the hardness. of car- in the hardness icant differences of oils fried in different types rot chips chips had indicator that the may be an discussed later in similar crispness as findings. the sensory characteristics moisture content of carrot chips: the higher the temperature, the higher the moisture content. Perhaps at higher temperatures, the crust forms more quickly and blocks water release from the carrot slice matrix. As indicated by the lower lightness (L) value, the higher temperature also caused the browning reaction to occur faster and that may have affected the color development. In deep-fried onion slices, Hansen (1998) found that the moisture content after frying and color development of the fried product, expressed as hue angle (Hue present study, but not in moisture con- but not in moisture study, present tent of carrot chips, among the types of oil with canola oil resulting in the high- temperature Frying est water activity. significantly affected (

Food Chemistry and Toxicology Carotenoid Content of Carrot Chips . . . carrot chips seemed to be more impor- carotene absorption. The good sensory References tant to the panelists in evaluating the characteristics of deep-fried carrot AOAC International. 2000. Official methods of analysis of AOAC International. 17th ed. Gaithersburg, acceptability of the carrot chips, al- chips could be an indicator of consum- Md.: AOAC International. p 39-2. though the flavor, color, and odor were er acceptance of this product. More- Arya SS, NetesanV, Premaavalli KS, Vijayraghavan still important. over, because chips are so popular PK. 1982. Effect of prefreezing on the stability of carotenoid in blanched air dried carrots. J Food The study reported here is part of a around the world, it can be expected Technol 17(1):109-113. project aimed at developing the best that this product will also be accepted Aukrust T, Blom H, Sandtorv B, Slinde E. 1994. Inter- action between starter culture and raw material method to produce carrot chips that worldwide. in lactic acid fermentation of sliced carrot. Leb- are highly acceptable, have good senso- ensm Wiss U Technol 27(4):337-341. ry characteristics, and have high caro- Conclusions Aukrust T, Blom H, Slinde E. 1995. Influence of brine composition on yield and quality of deep fried fer- tenoid content. We expect that this HE FRYING TEMPERATURE, BUT NOT mented carrot chips. Lebensm Wiss U Technol product or the processing method can Tthe type of oil, significantly affected 28(1):100-104. Baardseth P, Rosenfeld HJ, Sundt TW, Skrede G, Lea P, be introduced both in developed and the carotenoid content and vitamin-A Slinde E. 1995. Evaluation of carrot varieties for developing countries to alleviate nutri- activity of deep-fried carrot chips pre- production of deep-fried carrot chips: I. Chemical tion and health problems related with pared without lactic-acid fermentation. aspects. Food Res Int 28(3):195-200. Baardseth P, Rosenfeld HJ, Sundt TW, Skrede G, Lea P, carotenoid intake through a food-based Increasing frying temperature lowered Slinde E. 1996. Evaluation of carrot varieties for approach. the redness (a) value, decreased the production of deep-fried carrot chips: II. Sensory aspects. Food Res Int 28(6):513-519. Our study indicated that deep-fried carotenoid contents, darkened the col- Ball GFM. 1998. Bioavailability and analysis of vita- carrot chips were high in ␣-carotene or, and lowered the hardness value. No mins in foods. New York: Chapman & Hall. 569 p. and ␤-carotene with the estimated vita- differences among oil types were found Bao B, Chang KC. 1994. Carrot juice color, carotenoids and nonstarchy polysaccharides as affected by pro- min-A potency ranging from 2866 to in chip crispness, sweetness, and odor cessing conditions. J Food Sci 59(6):1155-1158. 3746 ␮g RAE per 100 g w/w chips. The scores by trained panelists. Negative Barua AB, Olson JA. 1998. Reversed-phase gradient

high-performance liquid chromatographic proce- Food Chemistry and Toxicology consumption of 1 serving of carrot correlations between L, a, and b values dure for simultaneous analysis of very polar to chips (30 g) is likely to meet the vita- and the color score of the carrot chips nonpolar retinoids, carotenoids and tocopherols min-A requirement of an adult (Insti- and positive correlations between the in animal and plant samples. J Chromatogr B 707:69-79. tute of Medicine 2001). This means that crispness and the sweetness scores and Biesalski HK. 1997. Bioavailability of vitamin A. Eur this product is a rich source of caro- the overall acceptability of carrot chips J Clin Nutr 51, Suppl 1:S71-S75. Biesalski HK, Böhles H, Esterbauer H, Fürst P, Gey F, tenoids, either as a vitamin-A precursor were observed. The frying temperature Hundsdörfer G, Kasper H, Sies H, Weisburger J. or antioxidant. The fat content of the significantly affected (P Ͻ 0.05) the 1997. Antioxidant vitamins in prevention. Clin chips may increase the bioavailability of overall acceptability of the chips, with Nutr 16:151-155. Block G. 1994. Nutrient sources of provitamin A car- carotenoids, as consistent results ob- the highest acceptability score being for otenoids in the American diet. Am J Epidemiol tained in animal models and humans carrot chips fried at 165 ЊC in PHSO. 139(3):290-293. Bushway RJ, Wilson AM. 1982. Determination of ␣- suggest that dietary fat is a key factor in and ␤-carotene in fruit and vegetables by high performance liquid chromatography. Can Inst Food Sci Technol J 15(3):165-169. Castenmiller JJM, West CE. 1998. Bioavailability and bioconversion of carotenoids. Ann Rev Nutr 18:19- 38. Chandler LA, Schwartz SJ. 1987. HPLC separation of cis-trans carotene isomers in fresh and processed fruits and vegetables. J Food Sci 52(3):669-672. Chen TM, Chen BH. 1994. Optimization of mobile phases for HPLC of cis-trans carotene isomers. Chromatographia 39(5/6):346-354. Chen BH, Peng HY, Chen HE. 1995. Changes of carotenoids, color, and vitamin A contents during processing of carrot juice. J Agric Food Chem 43(7):1912-1918. Craft NE, Sander LC, Pierson HF. 1990. Separation and relative distribution of all-trans-␤-carotene and its isomers in ␤-carotene preparations. J Mi- cronutr Anal 8:209-221. Desobry SA, Netto FM, Labuza TP. 1998. Preservation of beta-carotene from carrots. Crit Rev Food Sci Nutr 38(5):381-396. Dietz JM, Erdman JW. 1989. Effect of thermal processing upon vitamins and proteins in foods. Nutr To- day 24(4):6-15. Dimitrov NV, Meyer C, Ullrey DE, Chenoweth W, Mich- elakis A, Malone W, Boone C, Fink G. 1988. Bio- availability of ␤-carotene in humans. Am J Clin Nutr 48:298-304. Epler KS, Ziegler RG, Craft NE. 1993. Liquid chromatographic method for the determination of carotenoids, retinoids and tocopherols in human serum and in food. J Chromatogr 619:37-48. Fuchigami M, Hyakumoto N, Miyazaki K. 1995. Pro- grammed freezing effects texture, pectic composition and electron microscopic structure of carrots. J Food Sci 60(1):137-141. Hardenburg RE, Watada AE, Wang CY. 1990. The com- mercial storage of fruits, vegetables and florist and nursery stocks. United States Department of Agri- Figure 1—Effect of oil type and frying temperature on overall acceptability of culture, Agricultural Research Service, Agriculture deep-fried carrot chips (1 = dislike extremely, 9 = like extremely). abcvalues Handbook 66:130. with the same letters are not significantly different (P Ն 0.05). PHSO = partially Hagenimana V, Karuri EG, Oyunga MA. 1998. Oil hydrogenated soybean oil. content in fried processed sweetpotato products. J

Vol. 66, No. 9, 2001—JOURNAL OF FOOD SCIENCE 1263 Dau- -carotene cleav- -carotene cleav- ␤ ␤ -carotene response -carotene and other -carotene ␤ ␤ -tocopherol inhibit the develop- inhibit -tocopherol -carotene in healthy non-smoking ␣ ␤ ) during storage. J Food Sci 60(2):324- carotenoids in humans and animal models. Eur J carotenoids in humans and Clin Nutr 50, Suppl 3:S32-S37. of H. 1996. In vitro measurement considerations and age activity: methodological on the effect of other carotenoids 66(1):77-85. Res Vit Nutr Int J age. carotenes. J Food Sci dried encapsulated carrot 60(5):1048-1053. sic sensory methods for food evaluation. Ottawa, Canada: International Development Research Centre. 160 p. Essentials of human nutri- AS, editors. Truswell J, 637 p. Press. Univ. Oxford tion. Oxford: color and carotenoids of dehydrated carrots ( cus carota 326, 347. to supplementation with raw carrots, carrots juice to supplementation with or purified women. Nutr Res 16(4):565-575. carotene and carotene lesions in hypercholester- ment of atherosclerotic 67:197-205. Res Vit Nutr J Int olemic rabbits. of Univ. Davis, Calif.: recommendations. harvest and Information Research Vegetable California Center. enhances vegetables with added fat green leafy J Nutr 129:1549-1554. serum retinol. O, Mykkänen H. 1996. Serum Van Vliet T, van Schaik F, Schreurs WHP, van den Berg WHP, Schreurs van Vliet T, Schaik F, Van of spray- Stability JJ. 1995. Warthesen LA, Wagner 1989. Ba- LE, Elias LG. Ylimaki GL, Jeffery BM, Watts In: Mann Vitamin A and carotenoids. CE. 1998. West and starch affect 1995. Sulfite Chang KC. YP, Zhao MS20000439 Van Vliet T. 1996. Absorption of 1996. Absorption T. Vliet Van Suslow TV, Mitchell J, Cantwell M. 1998. Carrot post- Carrot M. 1998. J, Cantwell Mitchell TV, Suslow consumption of dark Children’s EEK. 1999. Takyi M, Häkkinen S, Hänninen Törrönen R, Lehmusaho This research was supported in part by the Nebraska Agricul- tural Research Division and is its Journal Series no. 12987. Authors Sulaeman, Giraud, and Driskell are with the Dept. of Nutritional Science and Dietetics, Authors NE 68583-0806. Lincoln, Nebraska, Univ. Of Food with the Dept. are Wehling and Taylor Lincoln. Nebraska, Univ. Science and Technology, Pro- with the Food are and Taylor Keeler Authors Direct Lincoln. of Nebraska, Univ. cessing Center, inquiries to author Driskell (E-mail: [email protected]). - 30 ␤ -carotene) in ␤ - and ␣ ed. New York: The MacGraw-Hill Co., Inc. Co., The MacGraw-Hill York: ed. New rd stationary phase. J Chromatogr B 678:187- 18 in cooked foods. J Agric Food Chem 23(6):1153- Agric Food foods. J in cooked 1157. and of retinol, tocopherol, mining concentrations tissue sam- in human plasma and five carotenoids Nutr 56:417-426. ples. Am J Clin of the separation of the stereoisomers phase HPLC carotenoids ( provitamin A Food Chem 55(1):63-72. dark green vegetables. frying. J Food Sci oil uptake during deep-fat 58(1):204-205, 222. the structure of carrots blanching and freezing on for food processing. J cells and their implications Sci Food Agric 77:223-229. the absorption of caro- Some dietary fibers reduce 129:2170-2176. tenoids in women. J Nutr of beta-car- SJ. 1998. Bioavailability Schwartz SW, in processed carrots otene is lower in raw than Nutr 128:913-916. and spinach in women. J Technol Food fat frying: factors and mechanism. 49(4):142-145, 152. Development of engineered stationary phases for the separation of carotenoid isomers. Anal Chem 66(10):1667-1674. ing effects on headspace volatiles and sensory attributes of carrots. J Food Sci 61(6):1191-1195. Liquid chromatographic determination of carotenoids in human serum using an engineered C 195. ersen G, Slinde E. 1997. Evaluation of carrot varieties for production of deep fried carrot chips: III. Carotenoids. Food Res Int 30(1):73-81. 1993 Lactic acid fermentation influence on sugar content and color of deep-fried carrot chips. Food Res Int 26:255-260. and procedures of statistics, a biometrical ap- 3 proach. 666 p. and a C Nierenberg DW, Nann SL. 1992. A method for deter- SL. 1992. A method Nann DW, Nierenberg reversed- Ryley J. 1996. An isocratic Nyambaka H, for IS. 1993. Criterion Saguy P, Weinberg Pinthus EJ, MC. 1998. Effect of Prestamo G, Fuster C, Risueno G. 1999. Wolfram J, Riedl J, Linseisen J, Hoffmann Flatt MT, Ruffin C, JL, Emenhiser CL, Lovalvo Rock Oil uptake during deep- Saguy IS, Pinthus EJ. 1995. Wise SA. 1994. KE, Craft NE, Sharpless LC, Sander blanch- Water 1996. B. Girard T, Durance M, Shamaila Wise SA. 1996. LC, Sander Thomas JB, KE, Sharpless Skrede G, Nilson A, Baardseth P, Rosenfeld HJ, En- Rosenfeld P, A, Baardseth G, Nilson Skrede P. H, Baardseth Blom T, G, Aukrust E, Skrede Slinde DA. 1997. Principles JH, Dickey Torrie RGD, Steel Sun J, Giraud DW, Moxley, RA, Driskell JA. 1997. Moxley, DW, J, Giraud Sun - ␤ —Vol. 66, No. 9, 2001 66, No. —Vol. L.) cultivars. J L.) cultivars. -carotene, fat intake, and ␤ -carotene, carotenoids and ␤ Daucus carota JOURNAL OF FOOD SCIENCE of methods for calculating retention of nutrients Potato chips fried in canola and/or cottonseed oil Sci 58(5):1079-1083. J Food maintain high quality. sugars and amino acids in the color development of fried potatoes. J Food Sci 51(1):157-160. cation of cis-trans isomers of provitamin A carotenoids in fresh and processed fruits and vegetables. J Agric Food Chem 45(10):3728-3732. of food, principles and practices. New York: Chap- York: New of food, principles and practices. man & Hall. 819 p. the prevention of coronary heart diseases. J Nutr 129:5-8. dence of a role of carotenoids in cardiovascular disease prevention. Am J Clin Nutr 62:1370S- 1376S. sponse of all-trans and 9-cis isomers of beta-carotene in humans. J Am Coll Nutr 15(6):620-624. Serum retinol concentrations in children are af- Serum retinol concentrations fected by food sources of Am J Clin Nutr anthelmintic drug treatment. 68:623-629. activity of carrot ( activity of carrot fense. Am J Clin Nutr 63:985S-990S. quality of deep-fat fried onion slices. Irish J Agric fried onion slices. quality of deep-fat Food Res 37:61-67. 38(3):609-612. Agric Food Chem intakes for vitamin C, es. 2000. Dietary reference Washington, carotenoids. vitamin E, selenium, and p 325. Press. Academy National D.C.: Food Proc Preserv 22:123-137. Preserv Food Proc for vitamin A, vita- 2001. Dietary reference intakes iodine, copper, min K, arsenic, boron, chromium, nickel, silicon, va- iron, manganese, molybdenum, Washing- copy). nadium, and zinc (prepublication p 4-1 to 4-61. Press. Academy National ton, D.C.: carotene and ascorbic acid retention in fresh and ascorbic acid retention carotene and J Food Sci 64(5):929-936. processed vegetables. Murphy EW, Criner PE, Gray BC. 1975. Comparisons BC. 1975. CrinerPE, Gray EW, Murphy Melton SL, Trigiano MK, Penfield MP, Yang R. 1993. Yang MP, MK, Penfield Trigiano SL, Melton Marquez G, Anon MC. 1986. Influence of reducing Lessin WJ, Catigani GL, Schwartz SJ. 1997. Quantifi- WJ, Lessin Lawless HT, Heymann H. 1998. Sensory evaluation H. 1998. Sensory Heymann Lawless HT, Kritchevsky SB. 1999. Kohlmeier L, Hasting SB. 1995. Epidemiologic evi- Johnson EJ, Krinsky NI, Russell RM. 1996. Serum re- Jalal F, Nesheim MC, Agus Z, Sanjur D, Habicht JP. 1998. JP. Habicht D, Agus Z, Sanjur MC, Nesheim F, Jalal Heinonen MI. 1990. Carotenoids and provitamin A 1990. Carotenoids and Heinonen MI. 1999. BP. AK, Klein Perry AD, Wong LA, Howard Oxidative damage and de- Jacob RA, Burri BJ. 1996. Hansen SL. 1998. Influence of oil temperature on the Influence of oil temperature Hansen SL. 1998. Academy of Scienc- Institute of Medicine, National Institute of Medicine, National Academy of Sciences. Institute of Medicine, National 1264 Carotenoid Content of Carrot Chips . . . Chips Carrot of Content Carotenoid

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