Design of a Beverage from Whey Permeate
Transcription
Design of a Beverage from Whey Permeate
JFS S: Sensory and Nutritive Qualities of Food Design of a Beverage from Whey Permeate J ANINE BEUCLER, MARYA NNE DRAKE, AND E. ALLEN FOEGEDING Introduction T he non-solid, or yellow-green, liquid that separates from the curd during natural cheese production is whey (Anonymous 2001; Smithers and others 1996; Chandan and others 1982). During the production of 1 pound of cheese, approximately 9 pounds of whey are produced (Anonymous 2001). Liquid whey is approximately 93% water and 0.6% protein (Huffman 1996), and contains almost 50% of all solids present in whole milk (Chandan and others 1982), of which lactose is the main constituent (Huffman 1996). Until the latter part of the 1900s, milkfat was the most important economic component of milk. Now, protein is the most highly valued component (Hardham 1998). The emergence of whey protein as a functional ingredient and good source of essential and branched chain amino acids has thrust whey protein into the market spotlight. To concentrate whey protein, liquid whey is subjected to ultrafiltration and microfiltration processes (Huffman 1996). Whey protein concentrate (WPC) contains protein in concentrations less than 90% while whey protein isolates (WPI) contain a minimum of 90% protein. What is left over after ultrafiltration and microfiltration of liquid whey in whey protein processing is called whey permeate (WP). Liquid WP is comprised primarily of lactose (5%), water (93%), and minerals (0.53%) with minimal fat (0.36%) and protein (0.85%) (Chandan and others 1982; USDA 2004). In its spray-dried form, these contents are concentrated to the following amounts: lactose 65% to 85%, minerals 8% to 20%, fat 1.5% maximum, and protein 3% to 8% (USDEC 2000). WP is primarily viewed as a byproduct in the food industry. Today, some WP is used as an ingredient in animal feed, primarily the lactose component (Frank 2001), and some WP is spread onto land. Increasing demand and production of WPC and WPI have produced a lucrative alternative to liquid whey disposal. However, WP still poses a problem. WP has been used in recent years for the production of lactic acid MS 20040628. Submitted 9/17/04, Revised 11/17/04, Accepted 1/6/05. Authors Beucler, Drake, and Foegeding are with Dept. of Food Science, North Carolina State Univ., Box 7624, Raleigh, N.C. 27695. Direct inquiries to author Drake (E-mail: mdrake@unity.ncsu.edu). © 2005 Institute of Food Technologists Further reproduction without permission is prohibited using fermentation with lactic acid bacteria (Talabardon and others 2000; Fitzpatrick and O’Keeffe 2001; Fitzpatrick and others 2001; Macedo and others 2002). Limited research has been conducted regarding the use of WP in the food industry. Rustom and others (1998) used the lactose component of WP to produce oligosaccharides for use as a functional ingredient in food products. ß-Galactosidase was used for hydrolysis of the lactose. A 2nd study utilized hydrolyzed WP for the production of permeate syrups to replace up to 50% of sucrose syrup in canned peaches and pears without a reduction in quality (Tweedie and MacBean 1978). In a similar study, Chandan and others (1982) reported that either hydrolyzed or unhydrolyzed WP could be used in the formation of a brine replacer in canned beans. Milk permeate (MP) is a lactose-rich byproduct of the ultrafiltration of liquid milk during the production of specialty milk products (Talabardon and others 2000). Its composition is similar to WP, and similar to WP, it is primarily a waste-stream product. Al-Eid and others (1999) evaluated replacing sucrose in white pan bread with fermented and unfermented MP. Geilman and others (1992) utilized hydrolyzed MP to produce an electrolyte beverage. They found using limited sensory analysis that beverages made with 100% MP were salty and that further testing would be required to produce a consumer-friendly formulation. The beverage market represents a large and growing industry within which there are several categories (Williams 2001). Electrolyte or sports beverages are designed to deliver rehydration, and they fall into the functional beverage category. Functional beverages offer some type of health benefit, and this category is a rapidly growing sector of the beverage market. The still drink market, which includes functional beverages, grows at an annual rate of 7%, double that of carbonated counterparts and encompasses a wide array of beverages (Williams 2001). Thirst quenching is a consumer term that may potentially be applied to any beverage (McEwan and Colwill 1996). The objectives of this study were 1st, to characterize via descriptive analysis, the sensory properties of commercial thirst-quenching beverages. For the 2nd objective, a beverage was designed from WP to fit into the concept of thirst-quenching beverages. Third, consumer acceptance and perception of commercial beverages and beverages made with WP was probed. Previous research with MP with limited sensory analysis (GeiVol. 70, Nr. 4, 2005—JOURNAL OF FOOD SCIENCE S277 Published on Web 4/28/2005 S: Sensory & Nutritive Qualities of Food ABSTRA CT meate ((WP) WP) is a b ypr oduct of whey pr otein ingr edient pr oduction, and pr imar ily contains water ABSTRACT CT:: Whey per permeate bypr yproduct protein ingredient production, primar imarily water,, ity of the WP pr oduced in the U nited S tates is disposed lactose als otein. The major produced United States lactose,, and miner minerals als,, with minimal fat and pr protein. majority er age of via land-spr eading or is used as a component in animal feed. H owev er ed in the gr owing bev land-spreading Ho ever er,, WP could be utiliz utilized gro bever erage industr y. The objectiv es of this study w er e to conduct descr iptiv e sensor y analysis of a wide selection of commer cial industry objectives wer ere descriptiv iptive sensory commercial bev er ages and to design a bev er age utilizing WP iptiv e sensor y pr ties (visual, flav or e/mouthbever erages bever erage WP.. The descr descriptiv iptive sensory proper operties flavor or,, and textur texture/mouthoper er ages w er e deter mined using a tr ained descr iptiv e panel ((n n = 11). WP with and without feel) of fifteen commer cial bev trained descriptiv iptive commercial bever erages wer ere determined hydrolysis of lactose was subsequently incorporated into a basic beverage formula, substituted for 0%, 25%, 50%, 75%, or 100% of water onsumers ((n n=1 00) ev aluated bev er ages with WP and commer cial bev er ages for o ver all acceptabilwater.. C Consumers 10 evaluated bever erages commercial bever erages ov erall ity or liking, and thirst-quenching ability wer lev els (25% and 50%) of either hy dr olyz ed or ity,, flav flavor ability.. D Drrinks made with lo low levels hydr drolyz olyzed ties than bev er ages unhy dr olyz ed WP w er e mor e similar to the commer cial bev er ages in visual and flav or pr oper bever erages unhydr drolyz olyzed wer ere more commercial bever erages flavor proper operties containing higher per centages (75% and 100%) of WP inks made with WP w er e higher in electr olyte (N a, K, Zn, percentages WP.. All dr drinks wer ere electrolyte (Na, Mg, P) content compared with a commercial sports beverage ((P P < 0.05). Beverage incorporation represents a valueadded utilization for lo w lev els of WP low levels WP.. Keywords: whey permeate, beverages, thirst-quenching, sensory analysis, consumer acceptance Beverage from whey permeate . . . lman and others 1992) suggested that WP might be suitable in sports beverages, however our goal was to initially explore a wider range of possible beverage applications for WP so we focused on the very wide category of thirst-quenching beverages. Materials and Methods Descriptive sensory analysis S: Sensory & Nutritive Qualities of Food Descriptive analysis was approved by the Univ. Institutional Review Board. Eleven panelists were selected based on interest, time availability, and sensitivity to basic tastes. Each panelist (3 male, 8 female) had at least 40 h of previous descriptive sensory analysis training using basic tastes and the Spectrum technique (Meilgaard and others 1999). Thirteen additional training sessions, lasting 45 min each, were conducted to instruct the panelists on identification and scale attributes. During 2 initial training sessions that included tasting and discussion of an array of commercial beverages, panelists identified 12 descriptive attributes: fruit flavor intensity, fruit aroma intensity, color intensity, opacity, brightness, sweet, sour, salty, bitter, astringency, viscosity, and carbonation (Table 2). Two additional terms, brothy and dairy sour, were added subsequently when the panel evaluated beverages with WP. During training, panelists evaluated and discussed sensory properties of commercial beverages to minimize within and between panelist variability. Statistical analysis of panel and panelist performance was applied prior to experimentation to confirm that the panel was trained and calibrated. Samples (30 mL) of each refrigerated beverage were placed into 60 mL soufflé cups with lids and three-digit random codes (Sweetheart Cup Co., Owings Mills, Md., U.S.A.). One hour prior to tasting, samples were removed from the refrigerator and allowed to temper to 12°C. Panelists evaluated each sample while seated in partitioned sensory booths under white lights. Samples for determination of visual attributes were placed in clear 150 mL cups (Sweetheart Cup Co., Chicago, Ill., U.S.A.) containing 30 mL of each sample and were placed on a white background. Visual analysis was conducted separately. Sample order for both the flavor and the visual analyses were randomized separately and balanced. Samples were presented monadically with ambient temperature spring water and crackers provided to each panelist to cleanse the palate. Each of the drinks was evaluated in quadruplicate by each panelist. Fifteen commercial beverages (C1-C15) were selected for descriptive analysis. Beverages spanned a wide range of beverage types and included carbonated sodas (C1, C4, blue raspberry and raspberry flavors), seltzer water (C10, raspberry flavor), sports-type beverages (C5, blue raspberry flavor, C15, generic berry flavor, no color), fruit-flavored drink (C8, generic berry flavor, no natural juice, blue color), fruit juice (C9, purple grape juice), fruit-flavored mineral and vitamin waters (with and without added sweeteners, no color) (C2, C6, C11, C14, raspberry flavor), fruit juice/tea beverages (C12, C13, raspberry and blackberry flavors), a milk/juice beverage (C3, generic berry flavor), and bottled water (C7). All beverages were shelf-stable. Beverages were purchased at local grocery and convenience stores. Following preliminary assessment of common flavoring themes among commercially available beverages, berry flavor (primarily raspberry and blue raspberry) was chosen for this study, as this was a common and prevalent flavor across all beverage types. Data from commercial beverages were analyzed and used in preliminary sensory tests of WP beverages to fine-tune WP beverage formulation. WP acquisition Frozen liquid mozzarella WP (151.4 L) was received by overnight carrier from a large commercial cheese and whey protein manufacturing facility (Tulare, Calif., U.S.A.). WP was frozen to facilitate S278 JOURNAL OF FOOD SCIENCE—Vol. 70, Nr. 4, 2005 expedient cross-country shipment. WP was kept frozen at –20°C until use (within 2 mo) and thawed at 5°C before use. Proximate analysis Proximate analysis of WP was conducted using standard methods (Bradley and others 1992). Total solids were measured using a Mojonnier Tester (Mojonnier Bros. Co., Chicago, Ill., U.S.A.) (Atherton and Newlander 1977). The Babcock method was used for fat analysis in addition to utilization of the CEM Smart Trac Rapid Fat Analysis System (CEM Corp., Matthews, N.C., U.S.A.) (CEM Smart Trac Rapid Fat Analyzer Instruction Manual). Total nitrogen was analyzed via the Kjeldahl method and protein was calculated by the conversion factor of total nitrogen (mg/L × 6.38/1000 = g/L protein). pH was measured using an Orion Model 250A Plus pH Meter with a Corning G-P Combo RJ probe (Fischer Scientific, Pittsburgh, Pa., U.S.A.). Percent titratable acidity was calculated from the amount of 0.1 N NaOH titrated into an 18-g sample until a final pH of 8.3 was reached. Mineral analysis of sodium, potassium, magnesium, zinc, and phosphorous was determined via inductively coupled plasma analysis. Microbial counts (total aerobic plate count and coliforms) were determined by appropriate dilutions in 0.1% peptone water and followed by pour-plating with tryptic soy agar or violet red bile agar (Acumedia Manufacturers Inc., Baltimore, Md., U.S.A.) and incubation at 35°C for 24 h. All analyses were conducted in duplicate. Hydr olysis of WP drolysis Hydrolysis of WP was conducted enzymatically using lactase (Maxilact® enzyme 1000 U/mL) (DSM Food Specialties Inc., Menomonee, Wis., U.S.A.). Methods used by Chandan et al. (1982) were utilized. Prior to hydrolysis, WP was pasteurized by heating to 72°C for 30 s in a stainless steel container followed by cooling on ice to 35°C. Hydrolysis was conducted at 35°C for 3 h. WP was subsequently heated to 63°C for 30 min for enzyme inactivation per manufacturer’s instructions. Samples were then immediately cooled on ice. The glucose concentration of hydrolyzed and (control) unhydrolyzed WP was determined colorimetrically using a glucose oxidase kit (Randox Laboratories Ltd., San Diego, Calif., U.S.A.). At time points 0, 1.5, and 3 h of enzyme hydrolysis, 1 mL WP was removed, and the lactase enzyme was heat inactivated as described previously. The sample was centrifuged to separate out the solids and a 1:10 dilution was made. Glucose concentration was then determined according to manufacturer’s directions. In addition, hydrolyzed and unhydrolyzed WP was evaluated by trained sensory panelists (n = 7) to determine if sweet taste increased after hydrolysis. WP beverage formulation Based on preliminary assessment of WP flavor and examination of the commercial beverage results, a still (noncarbonated) beverage similar to a flavored sports beverage appeared to be the best platform for WP incorporation. Four berry-flavored beverage formulations were initially screened. Beverage formulations varied in sweetener amount and flavoring. Based on comparable flavor and sweet taste intensities to commercial beverages, a beverage formulation for a fruit-flavored water was chosen for WP incorporation (Century Foods Intl., Sparta, Wisconsin, U.S.A.) (Table 1). Beverages with and without WP or hydrolyzed WP were subsequently made from various percentages of deionized water and WP (0%, 25%/75%, 50%/50%, 75%/25%, 100%). Additional ingredients were added and mixed, followed by pasteurization (heating to 72°C in a stainless steel container), and subsequent cooling on ice prior to refrigeration at 5°C. WP beverages evaluated included a control (100% water), 4 beverages containing hydrolyzed WP in concentrations of 25%, 50%, 75%, and 100% (H25, H50, H75, URLs and E-mail addresses are active links at www.ift.org Beverage from whey permeate . . . Ingredient Water/permeate (986 mL = 100%) Fructose Blue raspberry flavora Blue raspberry flavora Citric Acid Trisodium phosphate Sodium benzoate Vitamin Ca Pantothenic acida Vitamin B6 a Niacina Amount Source 0%, 25%, 50%, Tulare, Calif., U.S.A. 75%, 100% 70 g A.E. Staley Manufacturing Co. (Decatur, Ill., U.S.A.) 0.5 mL Mother Murphy’s Laboratories, Inc. (Greensboro, N.C., U.S.A.) 0.5 mL Flachsmann (Brampton, Ontario, Canada) 3g Cargill Foods, Inc. (Eddyville, Iowa, U.S.A.) 0.5 g Astaris (Webster Groves, Mo., U.S.A.) 0.7 g Cargill Foods, Inc. (Eddyville, Iowa, U.S.A.) 80 mg Roche Vitamins Inc. (Belvidere, N.J., U.S.A.) 5 mg Roche Vitamins Inc. (Belvidere, N.J., U.S.A.) 0.3 mg Roche Vitamins Inc. (Belvidere, N.J., U.S.A.) 15 mg Roche Vitamins Inc. (Belvidere, N.J., U.S.A.) a These items were added after pasteurization and cooling. H100), and 4 beverages containing unhydrolyzed WP (U25, U50, U75, U100) in the same percentages. WP beverages were evaluated in quadruplicate by the trained descriptive panel as described previously. Prior to analysis of WP beverages, panelists received 16 h of refresher training on sensory analysis of beverages. Refresher training included review and discussion of the previously evaluated commercial beverages as well as sensory analysis and discussion of WP and beverages containing WP. WP descriptive results were analyzed individually and together with the previously gathered descriptive data on commercial beverages to determine how WP beverages were characterized relative to commercial beverages and to select representative beverages for consumer testing. Consumer testing Consumer testing was approved by the Univ. Institutional Review Board. An informed consent form listing ingredients and potential ingredients in the commercial and WP beverages was signed by each participant prior to tasting. Faculty, staff, and students participated in the study. Based on descriptive sensory analysis results, including examination of individual attribute means and principal component analysis, thirteen representative beverages (7 commercial, 6 WP beverages) were selected for consumer testing. Commercial beverages were purchased within a week of the study, and WP beverages were made within 2 d of the study and stored at 5°C until the test day. Consumer evaluations (n = 100) were conducted across 4 different days. A constant control (bottled water) was presented each day with 3 other beverages. The constant control sample was used to reduce sample testing bias that could be associated with testing across 4 d (Young and others 2004; Thompson and others 2004). Prior to tasting, consumers were asked to fill out a questionnaire regarding age, gender, shopping habits, beverage consumption habits, feelings about the “thirst-quenching” ability of particular drinks or types of drinks, and attitudes toward different sugars. A definition of the term “thirst-quenching” was provided on the ballot: “a beverage you perceive to be refreshing” or “a beverage that you consume when you are thirsty.” Panelists were also asked, prior to tasting, to rate the 3 most thirst-quenching drinks, 1 being the most thirst quenching and URLs and E-mail addresses are active links at www.ift.org Table 2—Sensory language for descriptive sensory analysis of beverages Attribute Fruit aroma Fruit flavor Brothy Dairy sour Sweet a Soura Saltya Bittera Astringency a Viscosity Carbonation Opacity Definition Aromatics associated with different fruits evaluated orthonasally Aromatics associated with different fruits evaluated retronasally Aromatics associated with boiled meat or vegetable soup stock Aromatics associated with fermented yogurt Taste sensation associated with sugar Taste sensation associated with citric acid Taste sensation associated with NaCl Taste sensation associated with caffeine Shrinking, drawing, or puckering of the oral epithelium as a result of exposure to substances such as alum or tannins Force required to move a spoon back and forth in product Presence of carbon dioxide bubbles in a beverage The degree to which a liquid is opaque Reference Grape juice = 7 Green Gatorade = 4.5 Grape juice = 7.5 Green Gatorade = 4 Canned potatoes Wylers low sodium beef broth cubes Plain yogurt 10% and 5% sucrose in water 0.05% and 0.08% citric acid in water 0.3% and 0.5% NaCl in water 0.05% and 0.08% caffeine in water Grape juice = 7 Tea solution (6 tea bags soaked in 1 quart hot water for 1h) Water = 1 Cream = 3 Soda water, seltzer water Whole milk = 15 Grape juice = 12 Green Gatorade = 3 Color intensity The intensity or strength Grape Juice = 13 of a color from light to dark Juice tea = 6.5 Green Gatorade = 4 Brightness The chroma or purity of Juice tea = 6 the color, ranging from dull/ Grape juice = 4 muddied to pure/bright color Green Gatorade = 12 a Definitions and references taken from Meilgaard and others (1999). 3 the least, out of a list of 16 various commercial beverages. Consumers were asked which flavors (fruit punch, grape, berry, citrus, no flavor/water) they felt were the most thirst quenching. Samples (30 mL) were placed in clear 150 mL cups (Sweetheart Cup Co., Chicago, Ill., U.S.A.) without lids as panelists arrived and served at 10°C (beverages were kept on ice until poured). Samples were presented to consumers in balanced random order and cups were labeled with random three-digit codes. Samples were presented monadically and ambient temperature water and crackers were given to each consumer to cleanse the palate. Consumers were asked to evaluate each sample for overall liking, appearance liking, overall mouthfeel liking, fruit flavor and sweetness liking, and overall thirstquenching liking on a 9-point hedonic scale that was anchored on the left by “dislike extremely” and on the right by “like extremely.” Fruit flavor and sweetness intensity as well as thirst-quenching ability were also measured on a numerical 9-point intensity scale anchored on the left by “low” and on the right by “high.” Statistical analysis Statistical analysis was conducted by univariate and multivariate analysis of variance. Analysis of variance with means separation was conducted to determine differences between treatments. Linear relationships among descriptive and consumer attributes were determined using correlation analysis. For correlations, statisVol. 70, Nr. 4, 2005—JOURNAL OF FOOD SCIENCE S279 S: Sensory & Nutritive Qualities of Food Table 1—Beverage formulation (based on 1 L) Beverage from whey permeate . . . Table 3—Sensory attributes of WP with and without hydrolysis Without hydrolysis average With hydrolysis average Brothy Cooked/Milky Cardboard 1.00a 1.04a 1.66a 2.00a 0.58a 0.89a Sweet Sour Salty 1.00b 2.58a 0.25a 0.58a 1.00a 1.39a Astringency 1.25b 2.15a Means in a column followed by different letters are significantly different P < 0.05. tical significance was adjusted using Bonferoni’s correction. Principle component analysis was conducted on descriptive and consumer data separately to assess how all treatments were grouped. Consumer perceptions/feelings about different sugars were evaluated in pairwise comparisons by frequency distribution using Bowker’s test of symmetry (a nonparametric chi square type test for multiple analyses with the same population). Statistical analysis was conducted using SAS, version 8.2 (Cary, N.C., U.S.A.). Results and Discussion Physical measur ements of WP measurements WP, as received, contained 2.15 ± 0.23 log colony-forming units/ mL on tryptic soy agar pour plates and 1.19 ± 0.02 log colony-forming units/mL on violet red bile agar pour plates. Pasteurized WP contained less than 10 colony-forming units/mL on both tryptic soy agar and violet red bile agar plates. Fat content of WP was less than 0.1% (Babcock method) and 0.018% ± 0.01% fat (CEM Smart Trac Rapid Fat Analyzer). WP contained 260 ± 100.4 mg/L calcium, 1340 ± 509.5 mg/L potassium, 59.8 ± 23 mg/L magnesium, 450 ± 195.7 mg/L sodium, 335 ± 133.3 mg/L total phosphates, and 0.175 ± 0.095 mg/L zinc. Average total N of WP was 424.8 ± 126.0 mg N/L. Average total protein for WP was 2.48 ± 1.09 g/L and average total solids were 4.2% ± 1.6%. Average pH of unhydrolyzed and hydrolyzed WP was 6.45 ± 0.08. Initial glucose content of WP was 0.8 ± 1.0g/L of glucose. Glucose levels in WP increased up through 3 h of enzyme hydrolysis (data not shown). Thereafter, glucose levels remained constant (P > 0.05). After 3 h of hydrolysis, average glucose content was 23.4 ± 5.1 g/L. Descriptive sensory analysis of the WP with and without hydrolysis revealed that WP was characterized by mild flavors previously documented in liquid whey and whey ingredients (Drake and others 2003) and that sweet taste increased following lactose hydrolysis (Table 3). Beverage pH Beverages were designed to be similar in all aspects to commercial beverages; therefore pH was measured across all beverages, commercial and WP. The average pH of the commercial beverages was 3.69 ± 1.27. The pH of commercial beverages ranged from 2.78 ± 0.01 to 6.69 ± 0.00. Most commercial beverages (14/15) were between 2.78 ± 0.01 to 4.15 ± 0.02. The pH of the WP beverages increased as more permeate was added to each beverage. The control formulations made with 0% WP had an average pH of 3.03 ± 0.08 whereas the beverage formulations containing 100% permeate had an average pH of 4.37 ± 0.015. Hydrolysis had no effect on pH. S: Sensory & Nutritive Qualities of Food Descriptive sensory analysis of commer cial and WP bev er ages commercial bever erages Wide variability in aroma, flavor, mouthfeel, and appearance was observed among the commercial beverages. Significant differences were also observed among commercially purchased beverages and WP beverages for flavor and visual characteristics (Table 4). All sensory attributes discriminated the beverages. Correlation analysis (Table 5) revealed that fruit flavor and fruit aroma were highly correlated with one another. Fruit flavor was also correlated S280 JOURNAL OF FOOD SCIENCE—Vol. 70, Nr. 4, 2005 with color intensity and opacity, while opacity and color intensity were also correlated. Brothy and dairy sour were highly correlated. Finally, sour taste and astringency were correlated. Principal component analysis described a total of 80.9% of the variability on 4 principal components. PC1 described 31.7% of the variability and was characterized by the following attributes based on Eigenvector loadings: fruit flavor, fruit aroma, color intensity, and opacity; while PC2 described 28.6% of the variability and was characterized by dairy sour, brothy, bitter taste, sweet taste, and salty taste (Figure 1). Principal components 3 and 4 described the remaining 20.6% of the variability (Figure 2). PC3 (11.8%) was characterized by astringency and carbonation, while PC4 (8.8%) was characterized by viscosity, sour taste, and brightness. All 7 WP drinks were characterized by dairy sour and brothy notes. These flavors increased with added WP, and hydrolysis had no effect ( Table 4, Figure 1). These attributes (dairy sour and brothy) differentiated the WP beverages from the commercial beverages. WP beverages also had salty taste, but this attribute was not unique to them. Commercial beverage C5 had higher salty taste than WP beverages (Table 4). Consumer acceptance Demographic Data. The percentage ratio of male to female participants was 41%/59%. Thirty-nine percent of the participants fell into the 19 to 25 y age demographic, 55% were between the ages of 26 and 54 y. The remaining 6% were 55 to 65 y. Eighty-four percent were the major shopper for their household. Approximately 45% of consumers reported consuming thirst-quenching beverages at least once a week. The remaining 55% consumed these types of beverages sporadically. Sixty-four percent of the consumers responded that water was the most thirst-quenching beverage. GatoradeTM was a distant second with 18% scoring it as the most thirst quenching beverage. Other responses on the ballot included soda/pop (4%), milk (3%), Powerade (3%), and fruit juice (3%). A write-in category was also provided, but no responses were obtained. Consumers were also polled regarding what beverage flavor was the most thirst quenching. One hundred percent of polled consumers replied that no flavor/water was the most thirst quenching, while 96% to 99% also responded that the other flavors listed (citrus, berry, fruit punch, grape) were also thirst quenching. When asked to report when consumers drink thirst-quenching beverages, the most popular answers were “whenever I am thirsty” (46%) and “after exercise” (34%). “During exercise” and “before exercise” accounted for only 11% of the responses, while “with meals” and “with a snack” accounted for the remaining 9%. Consumers reported that they consumed thirst-quenching beverages primarily because they alleviate thirst (99%), have good flavor (98%), help to rehydrate the individual (99%), and are generally healthy (100%). Improved performance was slightly less of a motive for consumption (93.5%). Finally, all factors, price, flavor, health (99%), availability, and color (100%) influenced consumers’ choice of thirst-quenching beverages. Consumers perceptions/ feelings about different sugars were probed by responding to the statement “lactose is a healthy sugar,” followed by similar statements for glucose, sucrose and fructose. Results were similar for lactose, glucose, and fructose, with 44% to 50% agreeing with the statement, 36% to 38% neither agreeing nor disagreeing, and 5% to 7.5% disagreeing (Table 6) (P URLs and E-mail addresses are active links at www.ift.org Beverage from whey permeate . . . > 0.05). Consumer attitudes were more neutral for sucrose (P < 0.0001). Only 29% of consumers agreed that sucrose was a healthy sugar, while 45% neither agreed nor disagreed, and 19% disagreed with the statement that sucrose is a healthy sugar. Consumer Acceptance. There were no differences in liking attributes for the water across the 4 d of consumer testing (P > 0.05). Because consumer results across all attributes were consistent across the 4 d of testing (P > 0.05), consumer data across the 4 d were pooled. Water was by far the most liked beverage (Table 7). Water was followed by C9 (grape juice), C5 (sports beverage), C3 (shelf-stable milk/juice beverage), and C6 (fruit-flavored water) as the next most preferred beverages (average acceptance scores 6.63-6.35). The commercial beverage C12 (juice/tea blend) along with the control experimental formulation, U25, U50, and H50 were scored in the “like slightly” or “neither like nor dislike” categories (range 5.92 to 5.08). The remaining beverages H75, U100, and C10 (raspberry seltzer water), all scored values corresponding to “dislike” (range 3.67 to 3.26). Consumers noted differences among the commercial beverages in fruit flavor intensity, sweet taste intensity, and thirst-quenching ability. Commercial beverages also varied in appearance, mouthfeel, fruit flavor, sweet taste, overall liking, and thirst-quenching liking. In particular, C3, which was an opaque beverage, scored the lowest appearance liking scores. Beverage C10 was the only carbonated beverage, and it scored the lowest scores for thirst-quenching ability. WP beverages were scored by consumers as high in sweet taste intensity, but these drinks were rated low in sweetness liking. These results indicated that the Table 4—Mean values of descriptive attributes of commercial and WP beverages Drink Fruit aroma Fruit flavor Brothy Dairy sour Salty Bitter Sour Viscosity Astringency Carbonation Opacity Color intensity Brightness C1 4.80 3.49 0.00 0.00 0.32 0.00 2.27 1.18 1.54 9.99 2.87 4.29 11.71 C2 3.71 3.19 0.00 0.00 0.00 0.51 6.43 1.10 3.40 0.00 4.13 3.40 8.48 C3 6.84 6.51 0.00 0.00 0.00 0.00 2.43 1.58 1.53 0.00 11.66 5.56 3.99 C4 C5 C6 C7 C8 C9 C10 C11 C12 4.12 4.54 0.00 0.00 0.00 0.00 4.25 1.32 2.47 6.97 3.54 5.11 7.25 4.55 3.19 0.00 0.00 2.04 0.15 5.48 1.10 2.76 0.00 3.34 4.98 12.0 5.47 3.75 0.00 0.00 0.00 0.00 5.68 1.00 2.88 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.98 0.00 0.00 0.00 0.00 0.00 3.77 4.86 0.00 0.00 0.00 0.00 3.80 1.11 2.04 0.00 3.25 4.30 11.82 4.65 7.50 0.00 0.00 0.00 0.00 6.94 1.33 6.58 0.00 12.07 13.03 3.98 3.07 1.26 0.00 0.00 0.57 1.22 3.02 1.04 2.01 9.57 0.00 0.00 0.00 5.13 3.56 0.00 0.00 0.00 0.00 4.06 1.06 1.84 0.00 3.43 4.11 8.73 3.38 3.76 0.00 0.00 0.00 0.76 4.67 1.15 4.14 0.00 9.10 9.76 5.07 Drink C13 C14 C15 Control H25 H50 H75 H100 U25 U50 U75 U100 LSD Fruit aroma Fruit flavor Brothy Dairy sour Sweet Salty Bitter Sour Viscosity Astringency Carbonation Opacity Color intensity Brightness 3.43 3.77 0.00 0.00 6.37 0.00 0.57 4.98 1.14 4.04 0.00 5.96 6.56 6.00 3.87 3.93 0.00 0.00 6.42 0.00 0.66 4.71 1.13 4.17 0.00 6.50 6.81 5.35 2.98 3.55 0.00 0.00 6.07 0.00 1.02 4.41 1.02 2.04 0.00 0.00 0.00 0.00 4.50 3.66 0.00 0.33 6.90 0.00 0.00 4.77 1.00 2.90 0.00 2.55 3.08 9.23 3.70 3.38 0.00 1.00 7.40 0.50 0.00 4.20 1.18 2.46 0.00 2.70 2.90 8.40 3.14 2.80 0.90 1.86 7.80 1.15 0.00 4.00 1.30 2.30 0.00 2.80 2.40 8.30 2.77 2.50 1.48 2.50 7.90 1.55 0.00 3.90 1.45 2.40 0.00 3.50 2.30 7.00 2.65 2.36 1.36 2.40 7.60 1.30 0.00 3.75 1.46 2.40 0.00 4.20 2.50 6.20 4.34 3.45 0.00 0.83 7.56 0.00 0.00 4.40 1.13 2.50 0.00 2.80 2.80 8.48 3.20 2.90 0.75 1.74 7.30 0.90 0.00 3.99 1.30 2.28 0.00 2.80 2.60 8.37 2.90 2.58 1.00 1.80 7.60 1.08 0.00 3.65 1.28 2.18 0.00 2.90 2.50 7.90 3.40 3.26 0.00 1.13 7.45 0.58 0.00 3.88 1.23 2.46 0.00 4.05 2.68 6.46 0.82 0.67 0.18 0.22 0.78 0.30 0.31 0.80 0.16 0.62 0.43 0.48 0.56 0.74 Attributes were scored on a 15-point numerical scale where 0 = absence of attribute and 15 = very high intensity of the attribute. LSD = least significant difference P < 0.05. C1 to C15 are berry-flavored commercial beverages: C1 and C4 are carbonated sodas, C10 is seltzer water, C5 and C15 are sports-type beverages, C8 is a fruit drink, C9 is fruit juice, C2, C6, C11, C14 are fruit-flavored mineral and/or vitamin waters (with and without added sweeteners), C12 and C13 are fruit juice/tea beverages, C3 is a shelf-stable milk/juice beverage, and C7 is bottled water. Control = experimental beverages formulation made with 100% water. H25 to H100 = beverages made with hydrolyzed whey permeate substituted for 25%, 50%, 75%, or 100% of water, respectively. U25 to U100 = beverages made with unhydrolyzed whey permeate substituted for 25%, 50%, 75%, or 100% of water, respectively. Table 5—Correlations between descriptive sensory attributes used to profile beverages Fruit aroma Fruit flavor Dairy sour Brothy Sweet Sour Salty Bitter Astringency Viscosity Carbonation Opacity Color intensity 0.74a –0.35 –0.36 –0.33 –0.33 0.98a 0.44 0.26 –0.17 –0.06 0.19 0.50 0.37 –0.32 –0.07 0.53 0.34 –0.02 0.65 –0.59 –0.12 0.32 –0.03 0.68 –0.53 –0.12 –0.01 0.07 –0.58 0.00 0.16 0.09 0.79a –0.34 –0.05 0.28 0.25 0.30 0.19 0.22 0.54 –0.42 0.05 –0.26 –0.14 0.05 –0.15 –0.24 –0.19 –0.15 –0.22 –0.09 0.46 –0.19 –0.10 0.45 0.69a –0.18 –0.16 0.42 –0.04 –0.22 0.02 0.38 0.71a –0.22 Color intensity Brightness 0.34 0.71a –0.29 –0.26 0.22 0.37 –0.17 0.18 0.75a 0.17 –0.10 0.74a 0.22 0.13 0.21 0.18 0.54 0.16 0.36 –0.47 0.00 0.05 –0.01 0.04 0.22 a Significant correlations (P < 0.0001). URLs and E-mail addresses are active links at www.ift.org Vol. 70, Nr. 4, 2005—JOURNAL OF FOOD SCIENCE S281 S: Sensory & Nutritive Qualities of Food Fruit Fruit Dairy AstrinCarbonaroma flavor sour Brothy Sweet Sour Salty Bitter gency Viscosity ation Opacity Beverage from whey permeate . . . drinks were too sweet, an observation that was supported by written comments from consumers, 19% of whom wrote “too sweet.” Correlation analysis ( Table 8) revealed that overall liking was positively correlated to mouthfeel liking, sweetness liking, fruit flavor liking and to thirst-quenching ability and liking. Sweetness intensity was highly correlated only to fruit flavor intensity. Sweetness liking was correlated with overall liking, mouthfeel liking, fruit flavor liking, and thirst-quenching liking and ability. Fruit flavor intensity was highly correlated with sweetness intensity and fruit flavor liking. These results suggest that although consumers liked high intensities of fruit flavor, they did not perceive these drinks as thirst-quenching. Most importantly, thirst-quenching ability and liking were highly correlated to overall liking, mouthfeel liking, and sweetness liking. In general, consumers felt that the most thirst-quenching beverages were less sweet and had lower fruit flavor intensities. Principal component analysis was conducted to determine relationships between products and attributes. Results confirmed those observed by univariate analysis (Figure 3, Table 7). Seventy-five percent of the variability was explained on the 1st 2 components. PC1 explained 51.9% of the variability and was characterized by overall liking, appearance liking, mouthfeel liking, sweet liking, fruit-flavor liking, thirst-quenching ability, and thirst-quenching liking, while PC2 described 22.7% of the variability and was characterized by the following attributes: sweet intensity and fruit-flavor intensity. Beverage C10 was negatively associated with all attributes. Water was highly associated with thirst-quenching ability and liking, appearance liking, mouthfeel liking, and overall liking. Commercial beverages C6, C5, and C9 were all associated with fruit flavor intensity, fruit flavor liking, sweet liking, and, to a lesser extent, overall liking and mouthfeel liking. All WP drinks were characterized by sweet intensity, while U25, U50, and H25 were also characterized by fruit flavor intensity. These drinks were negatively associated with appearance liking and thirst-quenching ability and liking. There was an obvious gap between WP beverages containing Table 6—Consumer perception of the healthfulness of sugars (n = 100) Lactose is a healthy sugara Glucose is a healthy sugara Fructose is a healthy sugara Sucrose is a healthy sugarb 8% Strongly agree 50% Agree 37% Neither agree nor disagree 5% Disagree 0% Strongly disagree 10.6% Strongly agree 44% Agree 36% Neither agree nor disagree 7.5% Disagree 1.5% Strongly disagree 7.5% Strongly agree 48% Agree 38% Neither agree nor disagree 5% Disagree 0% Strongly disagree 5% Strongly agree 29% Agree 45% Neither agree nor disagree 19% Disagree 1% Strongly disagree a,b Differences in the distribution of consumer attitudes between the sugars (P < 0.0001). 50% or less WP and those containing 75% or more WP (Figure 3). Those beverages containing lower amounts (25% and 50%) of WP exhibited higher overall liking scores and were ranked closer to commercial beverages than those WP beverages containing 75% or more WP. Discussion Proximate analysis results for protein, fat, lactose, calcium, and potassium content of WP were within ranges published by the United States Dairy Export Council (2002). However, values for phosphorous, sodium, and magnesium were above the published ranges. S: Sensory & Nutritive Qualities of Food Figure 1—Principal component biplot of descriptive analysis of beverages. C1 to C15 are berry-flavored commercial beverages: C1 and C4 are carbonated sodas, C10 is seltzer water, C5 and C15 are sports-type beverages, C8 is a fruit drink, C9 is fruit juice, C2, C6, C11, C14 are fruit-flavored mineral and/or vitamin waters (with and without added sweeteners), C12 and C13 are fruit juice/tea beverages, C3 is a shelf-stable milk/juice beverage, and C7 is bottled water. U is unhydrolyzed WP beverage, followed by value that is the percentage of WP added, for example, U25. H is hydrolyzed WP beverage, followed by value that is the percentage of WP added, for example H25. PC is principal component. Percentage following PC in parenthesis explains amount of variability depicted by each principal component on each axis. Underlined samples were chosen for consumer testing. S282 JOURNAL OF FOOD SCIENCE—Vol. 70, Nr. 4, 2005 URLs and E-mail addresses are active links at www.ift.org Beverage from whey permeate . . . Table 7—Mean values of consumer liking attributes of commercial and WP beverages Overall liking Appearance liking Mouthfeel liking Fruit flavor intensity Fruit flavor liking Sweet intensity Sweet liking Thirst quenching ability Thirst quenching liking C3 C5 C6 C9 C10 C12 Control U25 U50 H50 H75 U100 Water LSD 6.39 3.92 6.47 6.73 6.50 6.95 6.47 5.70 5.71 6.44 6.75 6.96 6.35 6.30 6.42 6.51 6.44 6.44 6.35 7.40 7.06 5.84 6.23 6.20 6.12 6.31 6.22 6.63 7.04 6.66 8.15 7.46 6.34 6.64 5.55 5.50 3.26 6.53 4.37 2.60 2.71 2.33 3.16 3.82 3.43 5.72 7.06 6.49 6.96 6.21 5.63 6.02 5.59 5.52 5.25 5.61 5.84 6.44 5.55 7.43 5.42 5.47 5.29 5.08 6.19 6.13 6.18 5.29 7.23 5.25 5.35 4.98 3.67 5.40 4.86 5.68 4.00 6.94 4.21 4.06 3.79 3.67 6.25 5.44 5.81 4.50 7.14 4.48 4.74 4.29 7.48 7.71 7.57 1.29 5.22 1.51 5.90 8.04 7.93 0.57 0.57 0.56 0.48 0.47 0.62 0.62 0.59 0.60 5.92 7.10 6.80 6.08 5.75 6.61 6.19 6.18 6.01 5.71 7.02 6.35 6.54 5.35 7.17 5.87 5.70 5.52 Attributes were scored on a 9-point hedonic scale where 0 = absence of attribute or dislike extremely and 9 = very high intensity of the attribute or like extremely. LSD = least significant difference P < 0.05. C1 to C15 are berry-flavored commercial beverages: C1 and C4 are carbonated sodas, C10 is seltzer water, C5 and C15 are sports-type beverages, C8 is a fruit drink, C9 is fruit juice, C2, C6, C11, C14 are fruit-flavored mineral and/or vitamin waters (with and without added sweeteners), C12 and C13 are fruit juice/tea beverages, C3 is a shelf-stable milk/juice beverage, and C7 is bottled water. Control is experimental beverage made with no WP. U25, U50, U100 are beverages made with 25%, 50%, or 100% unhydrolyzed WP and H50 and H75 are beverages made with 50% or 75% hydrolyzed WP, respectively. a leading commercial sports beverage included in the study (C5) (Table 4), which suggests that salty taste intensity was not objectionable. Alternatively, the use of other flavorings or masking agents could cover unwanted brothy or dairy sour flavors present in WP beverages. Plain hydrolyzed WP was sweeter than unhydrolyzed WP via descriptive analysis. However, when incorporated into the beverage formulation with added fructose, there were no statistical differences in sweet taste via descriptive analysis between WP beverages containing hydrolyzed or unhydrolyzed lactose. Lactose hydrolysis did not affect acceptability of WP beverages, and consumer perceptions of various sugars also indicated that lactose was not perceived in a negative fashion compared with other sugars such as glucose, sucrose, and fructose. Because lactose hydrolysis is expensive and time-consuming, results suggest that hydrolysis of WP is not necessary for beverage incorporation. Johnson and others (1983) evaluated the relationship between Figure 2—Principal component biplot of descriptive analysis of beverages (PC3&4). C1 to C15 are berry-flavored commercial beverages: C1 and C4 are carbonated sodas, C10 is seltzer water, C5 and C15 are sports-type beverages, C8 is a fruit drink, C9 is fruit juice, C2, C6, C11, C14 are fruit-flavored mineral and/or vitamin waters (with and without added sweeteners), C12 and C13 are fruit juice/tea beverages, C3 is a shelf-stable milk/juice beverage, and C7 is bottled water. U is unhydrolyzed WP beverage, followed by value that is the percentage of WP added, for example, U25. H is hydrolyzed WP beverage, followed by value that is the percentage of WP added, for example H25. PC is principal component. Percentage following PC in parenthesis explains amount of variability depicted by each principal component on each axis. Underlined samples were chosen for consumer testing. URLs and E-mail addresses are active links at www.ift.org Vol. 70, Nr. 4, 2005—JOURNAL OF FOOD SCIENCE S283 S: Sensory & Nutritive Qualities of Food These differences may be due to differences in milk source or cheese type. All values for mineral content of WP were above levels present in typical electrolyte beverages such as GatoradeTM. The high level of sodium may account for the salty taste encountered in both plain WP and WP beverages. WP beverages exhibited salty tastes and low but distinct intensities of brothy and dairy/sour flavors. Geilman and others (1992) also reported high salty taste in formulated milk permeate (MP) beverages, however they did not investigate dilution of permeate prior to incorporation into a beverage. Although minimal sensory analysis was conducted by Geilman and others (1992), the focus in their study, which utilized no formal descriptive analysis and limited consumer analysis (n = 45), was on heat-stable and heat-developed flavors following ultra high temperature (UHT) heat treatments. Removal or reduction of sodium or potassium in WP via anion exchange or nanofiltration would reduce salty taste in WP beverages. However, salty taste intensity of WP beverages was less than that of Beverage from whey permeate . . . perceived sweetness intensity, flavor intensity, and color intensity in strawberry-flavored drinks. They reported that colored solutions were perceived by a consumer-like taste panel to have more intense flavors than their colorless counterparts. Also, darker-colored beverages were perceived to have stronger flavors than lighter-colored beverages. These findings were supported by studies conducted by Bayarri and others (2001) who determined that color enhanced the perception of sweet taste in orange-flavored drinks and enhanced the perceived intensity of flavors in peach-, kiwi-, orange-, and berry-flavored drinks. However, the intensity of this effect was dependent upon the product type and consumer expectations (Bayarri and others 2001). In our results, as the amount of WP added to beverages increased, the color intensity scores decreased on average. The fruit flavor intensity scores also dropped as more WP was added (Table 4). The same relationship between color and fruit flavor intensity was found in our study for WP beverages, although this effect could also have been due to flavors contributed by WP diminishing fruit flavor perception rather than color effects. Zellner and Durlach (2002) used a six-part questionnaire to probe consumer attitudes of thirst-quenching beverages. Their study determined that temperature, sweetness, and color were major factors influencing thirst-quenching ability or refreshingness of a beverage. Temperature was by far the most important factor. Cold temperature drinks were viewed as thirst quenching by 92% of those polled. The 2nd most common response was sweet taste (unspecified sweetness level), which influenced 50% of the consumers. Color was important to 24% of the consumers polled. Consumers felt that thirst-quenching beverages were typically clear, red, orange, yellow, or white. Unlikely refreshing colors included black, brown, green, gray, and purple (Zellner and Durlach 2002). Twelve percent of consumers in our study wrote that the blue color of the WP beverages was an odd color for a drink and that they would not choose this color for a beverage. However, there are multiple brands of blue-colored electrolyte (sports) and still-flavored beverages currently in the market. Zellner and Durlach (2002) reported that citrus and vanilla flavors were the most refreshing. Orange, strawberry, and lemon flavors correspond to the refreshing colors of orange, red, and yellow. Strawberry, the 2nd most thirstquenching flavor (Zellner and Durlach 2002), is a member of the berry flavor family. The choice to use berry-flavored drinks was therefore a wise decision, because most consumers are familiar with berry flavors and also feel that they are highly refreshing. Sweetness is a determinant of thirst-quenching liking and amount of beverage consumption. The presence of flavor and sweetness in a thirst-quenching beverage increased consumption in exercising individuals (Passe and others 2000). The addition of flavor and sweet taste to water was preferred over plain water in these same individuals (Passe and others 2000). The perceived intensity of sweet taste increases during an exercise bout and may therefore result in a decreased consumption of a beverage if the perceived sweet taste intensity is too high. A study by Cohen (1988) found a statistical difference in hedonic liking scores of carbohydrate-electrolyte drinks containing 6% and 8% carbohydrate. The 8% carbohydrate-electrolyte drink scored 6.2 ± 2.2, while the 6% carbohydrate-electrolyte scored 7.1 ± 1.4 on a 9-point hedonic scale for overall beverage liking, indicating that higher sweetness intensity was undesirable for thirst-quenching beverages (Cohen 1988; Passe and others 2000). Our results did not reveal a correlation between consumer perception of thirst-quenching and sweet taste intensity (Table 8). However, consumer perception of sweet taste intensity and sweet taste liking were not related, nor was sweet taste intensity and overall liking (Table 8). McEwan and Colwill (1996) reported that there were 7 attributes that consumers reported as being the most important in influencing the thirst-quenching characteristics of beverages: acid, astringent, carbonation, fruity, strength of flavor, sweetness, and thickness. Acid was most associated with thirst-quenching, while sweetness and thickness were least associated (McEwan and Colwill 1996) In our study, S: Sensory & Nutritive Qualities of Food Figure 3—Internal preference map of consumer perception of selected commercial and WP beverages (PC1&2). C1 to C15 are berry-flavored commercial beverages: C1 and C4 are carbonated sodas, C10 is seltzer water, C5 and C15 are sports-type beverages, C8 is a fruit drink, C9 is fruit juice, C2, C6, C11, C14 are fruit-flavored mineral and/or vitamin waters (with and without added sweeteners), C12 and C13 are fruit juice/tea beverages, C3 is a shelf-stable milk/ juice beverage, and C7 is bottled water. U is unhydrolyzed WP beverage, followed by value that is the percentage of WP added, for example, U25. H is hydrolyzed WP beverage, followed by value that is the percentage of WP added, for example H25. PC is principal component. Percentage following PC in parenthesis explains amount of variability depicted by each principal component on each axis. S284 JOURNAL OF FOOD SCIENCE—Vol. 70, Nr. 4, 2005 URLs and E-mail addresses are active links at www.ift.org Beverage from whey permeate . . . Table 8—Correlations between consumer liking attributes of beverages Appearance liking Overall liking 0.32 Appearance liking Mouthfeel liking Sweet intensity Sweet liking Fruit flavor intensity Fruit flavor liking Thirst quenching ability Mouthfeel liking 0.96a 0.40 Sweet intensity –0.09 –0.42 –0.03 Sweet liking Fruit flavor intensity Fruit flavor liking 0.91a 0.16 0.89a 0.27 0.10 –0.26 0.10 0.87a 0.48 0.80a 0.08 0.77a 0.38 0.95a 0.64a Thirst quenching Thirst quenching ability liking 0.91a 0.45 0.94a –0.25 0.73a –0.19 0.56 0.94a 0.44 0.95a –0.23 0.78a –0.14 0.61 0.99a a Significant correlations (P < 0.002). Conclusions D escriptive analysis revealed differences among all commercial and WP beverages. Only WP beverages exhibited brothy and dairy-sour flavors, and the intensity of these attributes was directly related to the percentage of WP added. WP beverages were also characterized by salty taste, but salty taste intensities were comparable or lower than commercial sports beverages. Consumer acceptability scores for WP beverages containing 25% and 50% WP were higher than those containing 75% and 100% WP, and these acceptance scores were comparable to several commercial beverages. WP in lower concentrations (25% to 50% substitution) may be successfully incorporated into a beverage application. Other applications should be investigated such as incorporation into a drinkable yogurt, where WP flavors may be successfully merged at higher concentrations. Acknowledgments This study was funded in part by the North Carolina Dairy Foundation. The use of trade names does not imply endorsement nor criticisms of ones not mentioned. Paper FSR05-13 of the Food Science Dept., North Carolina State Univ. URLs and E-mail addresses are active links at www.ift.org References Al-Eid SM, Al-Neshawy AA, Al-Shaikh Ahmad SS. 1999. Influence of substituting water with ultrafiltered milk permeate on dough properties and baking quality of white pan bread. J Cereal Sci 30:79–82. Anonymous. 2001. Whey. Do it with dairy. Available from Dairy Management Inc., Rosemont, Ill. www.doitwithdairy.com/infolib/ingspecsheet/factwhey.htm. Accessed June 15, 2004. Atherton HV, Newlander JA. 1977. Chemistry and testing of dairy products. Westport, Conn.: AVI Publ. Co. p 71–116. Bayarri S, Calvo C, Costello E, Duran L. 2001. Influence of color on perception of sweetness and fruit flavor of fruit drinks. Food Sci Tech Int 7(5):399–404. Bradley RL, Arnold E, Barbano DM, Semerad RG, Smith DE, Vines BK. 1992. Chapter 15 title. In: Marshall RT, editor. Standard methods for the examination of dairy products. 16th edition. Washington, D.C.: American Public Health Assn. p 433–516. Chandan RC, Uebersax MA, Saylock MJ. 1982. Utilization of cheese whey permeate in canned beans and plums. J Food Sci 47:1649–53. Cohen J. 1988. Statistical power analysis for the behavioral sciences. Hillsdale, N.J.: Lawrence Erlbaum Associates. Drake MA, Karagul-Yuceer Y, Cadwallader KR, Civille GV, Tong PS. 2003. Determination of the sensory attributes of dried milk powders and dairy ingredients. J Sensory Stud 18:199–216. Fitzpatrick JJ, Ahrens M, Smith S. 2001. Effect of manganese on Lactobacillus casei fermentation to produce lactic acid from whey permeate. Proc Biochem 36(7):671–5. Fitzpatrick JJ, O’Keeffe U. 2001. Influence of whey protein hydrolysate addition to whey permeate batch fermentations for producing lactic acid. Proc Biochem 37(2):183–6. Frank P. 2001. Finding the whey: Food processing. Meadow Fresh Marketing, Salt Lake City, Utah. Available from: www.legacy-meadowfresh.com/ Finding_The_Whey.html. Accessed June 15, 2004. Geilman WG, Schmidt D, Herfurth-Kennedy C, Path J, Cullor J. 1992. Production of an electrolyte beverage from milk permeate. J Dairy Sci 75:2364–9. Hardham JF. 1998. Effect of protein standardization of milk by addition of UF milk permeate on the composition and storage stability of UHT processed milk. Aust J Dairy Tech 53:22–7. Huffman LM. 1996. Processing whey protein for use as a food ingredient. Food Tech 50:49–52. Johnson LJ, Dzendolet E, Clydesdale FM. 1983. Psychophysical relationship between sweetness and redness in strawberry-flavored drinks. J Food Prot 46:21–5. Macedo MG, Lacroix C, Champagne CP. 2002. Combined effects of temperature and medium composition on exopolysaccharide production by Lactobacillus rhamnosus RW-9595M in a whey permeate based medium. Biotech Prog 18(2):167–73. Meilgaard M, Civille GV, Carr BT. 1999. Descriptive analysis techniques. In: Meilegaard M, Civille GV, Carr BT, editors. Sensory evaluation techniques. 3rd ed. Boca Raton, Fla.: CRC Press. p 173–83. McEwan JA, Colwill JS. 1996. The sensory assessment of the thirst-quenching characteristics of drinks. Food Qual Pref 7(2):101–11. Passe DH, Horn M, Murray R. 2000. Impact of beverage acceptability on fluid intake during exercise. Appetite 35:219–29. Rustom IYS, Foda MI, Lopez-Leiva MH. 1998. Formation of oligosaccharides from whey UF-permeate by enzymatic hydrolysis—analysis of factors. Food Chem 62(2):141–7. Smithers GW, Ballard FJ, Copeland AD, De Silva KJ, Dionysius DA, Francis GL, Godard C, Griece PA, McIntosh GH, Mitchell IR, Pearce RJ, Regester GO. 1996. New opportunities from the isolation and utilization of whey proteins. Symposium: advances in dairy foods processing and engineering. J Dairy Sci 79:1454–9. Talabardon M, Schwitzguebel J, Peringer P. 2000. Anaerobic thermophilic fermentation for acetic acid production from milk permeate. J Biotech 76:83–92. Thompson JL, Drake MA, Lopetcharat K, Yates MD. 2004. Preference mapping of commercial chocolate milks. J Food Sci 69(11):S406-S413. Tweedie LS, MacBean RD. 1978. The effect of partial replacement of sucrose by hydrolyzed whey lactose on the quality of canned peaches and pears. Food Tech Aust 12(4):128-131. [USDA] United States Dept. of Agriculture. 2004. Washington, D.C.: U.S. Dept. of Agriculture. Available from: www.nal.usda.gov/fnic/foodcomp/cgi-bin/ list_nut_edit.pl. Accessed June 15, 2004. [USDEC] United States Dairy Export Council. 2000. Reference manual for U.S. whey and lactose products. Arlington, Va.: U.S. Dairy Export Council. Williams LA. 2001. Trend setting drinks: The new developments and trends that will be shaping their industry in the years to come. World Food Ingred 11:45–48,50,52. Young N, Drake MA, Lopetcharat K, McDaniel M. 2004. Preference mapping of Cheddar cheeses. J Dairy Sci 87:11–9. Zellner DA, Durlach P. 2002. What is refreshing? An investigation of the color and other sensory attributes of refreshing foods and beverages. Appetite 39:185–6. Vol. 70, Nr. 4, 2005—JOURNAL OF FOOD SCIENCE S285 S: Sensory & Nutritive Qualities of Food sweet liking was correlated with overall liking and to thirst-quenching liking, however sweet intensity was not, confirming observations from these previous studies. In contrast, in our study a carbonated beverage (C10) was not considered thirst-quenching and scored the lowest scores for thirst-quenching ability and liking. Future studies with WP should investigate whether a substitute sweetener could be utilized or simply a lower amount of sweetener could be incorporated into the WP beverages to increase acceptance scores. Our results from commercial and WP beverages revealed 2 important issues. First, the control formulation was an accurate formulation given its centralized location among commercial beverages on the descriptive principle component plot (Figures 1, 2). Second, the addition of WP to the control formulation resulted in drinks more unlike commercial beverages. This conclusion is strengthened by the finding that the greater the amount of WP added to the formulation, the farther the WP beverages plotted from the commercial beverages on both descriptive analysis and consumer acceptability principal component analysis plots (Figures 1 to 3). Therefore, the greater the percentage of WP added to the beverage, the less like commercial beverages it became. WP beverages plotted in a grouping distinct from commercial beverages, while the control formulation plotted closely to the commercial beverages. These results suggest that while low levels (25% to 50%) of WP incorporation may be achievable in a viable commercial beverage, this platform may not be the most ideal application for the infiltration of WP into the food market. The more WP added, the less preferred and accepted beverages were by consumers. Some other food application such as a fruit smoothie or drinkable yogurt might be more feasible for WP incorporation, and future studies will address this option.