the interest in whey - protein supplement ( wps ) increased with consumer 's sensibility concerning health benefits , since the immunomodulatory role of wps has already been amply demonstrated [ 1 , 2 ] . the whey protein ( wp )
constitutes 20% of the total protein content of bovine milk and includes alpha - lactalbumin ( -la ) , beta - lactoglobulin ( -lg ) , bovine serum albumin ( bsa ) , lactoferrin ( ltf ) , immunoglobulins ( ig ) , and growth factors to tissues .
they are associated with the prebiotic effect , promoting tissue restoration , maintenance of intestinal integrity , destruction of pathogens , and elimination of toxins .
highly digestible and quickly absorbed by the body , the wps are widely used in situations of metabolic stress .
whey - protein concentrates ( wpcs ) and whey - protein isolates ( wpis ) usually contain a cysteine concentration at least four times higher than other high - quality proteins , and it produces an improvement in immune response .  
crohn 's disease ( cd ) is a complex chronic inflammatory disease , with periods of exacerbation , which affects the gastrointestinal tract , and may also involve the musculoskeletal system , skin , and eyes .
it is important to consider that although the cd may affect any portion of the digestive tract , in most cases it occurs more frequently in the small intestine .
the ileum and cecum are affected in 40% of cases , the small intestine in 30% , and colon in 25% . with this large percentage of presentation in the small intestine
the deregulation of the immune system associated with the intestinal mucosa leads to chronic inflammation , which leads to the destruction of intestinal epithelium and severe functional abnormalities , with loss of absorptive capacity and excessive secretion of electrolytes and intestinal fluids .
thus , cd individuals may show nutritional changes ranging from deficiency of trace elements to severe malnutrition .
several types of diets and supplements are able to modulate the immune system functions , and their bioactive components have been proposed to form the basis of functional immunomodulatory food product .
human and bovine milk contains the transforming growth factor  ( tgf- ) , multifunctional polypeptide with an important role in the development of tolerance and prevention of autoimmunity . despite the valuable functional and nutritional properties , it is important to note that wp has little or no flavour .
however , some compounds in whey are susceptible to chemical reactions , for example , lipid oxidation forming unpleasant aromas and flavours in the product [ 13 , 14 ] . today
, consumers increasingly expect to obtain pleasure from food and require sensory characteristics , for example , aroma , flavour , texture , and , along with these sensory characteristics , maintaining or improving their health and welfare . therefore , for cd patients ( who often require specific nutritional support ) to be encouraged to undertake the process of continuous alimentary supplementation , it is necessary to study the acceptability of the product , so that researchers and industries can adapt to the sensory quality of the product as expected by patients .   thus , the objective of this study was to evaluate the acceptability of an alimentary supplement of whey - protein concentrate ( wpc ) and tgf- , unavailable commercially , by patients with crohn 's disease .
it is the first time that a study about the acceptability of this supplement by cd patients is done . in this study
the supplement used was donated by an industry of cheese and whey products from california ( usa ) .
the supplement was constituted by whey - protein concentrate ( wpc ) with the addition of tgf- in the exogenous shape , but in amounts not reported by the company , since it is a supplement not marketed yet .  
the humidity , total solids , ash , and protein were established based on the methods of aoac .
total lipids were determined according to bligh and dyer   and total carbohydrates were estimated by difference , subtracting the sum of the values obtained in other measurements of 100% .
the water protein solubility ( % ) was determined according to the method of morr and foegeding .
total amino acids in the supplement were determined by reversed phase liquid chromatography , after acid hydrolysis ( 24  h ) , plus 20% of hcl phenol , followed by derivatisation with phenylisothiocyanate .
fifty - four individuals ( 24 male and 30 female ) who had cd and aged from 18 to 62 years ( median age of 37 years ) were invited to participate in this study .
it was conducted in the gastrocentro ( centre for diagnosis of digestive tract diseases ) , university of campinas ( unicamp ) , brazil .
the patients with cd performed the acceptance test of the supplement in a single session for the three attributes : aroma , flavour , and viscosity , according to the following criteria : ( a ) patients of both genders ; ( b ) attending outpatient department regularly .  
this study was approved by the local ethics committee under protocol 304/2007 , and all individuals signed an informed consent form before the sensory evaluation .
the patients conducted an acceptance test assessing the supplement in inflammatory intestinal disease outpatient clinic at gastrocentro ( unicamp ) .
such test was previously prepared by diluting 15  g of the product in 100  ml of filtered water at room temperature .
the test was performed in individual booths and during the morning from 9  :  00 to 11  :  00  h.   the cd patients assessed in a single session the acceptance of the product concerning the attributes : aroma , flavor , and viscosity by using nine - point facial hedonic scale in the extreme left and extreme right , under the term  terrible  and the term  great ,  as shown in figure 1 [ 19 , 20 ] .   to evaluate the acceptance results , the items of hedonic facial scale were converted into numerical values .
thus , the term  terrible  was converted into the number 1 , the term  very bad  was converted into the number 2 , the term  bad  into the number 3 , and so on , until the term  great ,  that was converted to number 9 in the scale . for aroma and flavour ,
the patients were also asked to quote the aromatic notes and flavours perceived in the supplement sample and to assess the product purchase intention .
the physicochemical data were assessed by calculating the average , standard deviation , and tukey 's test , by using the software spss 15.1 for windows .
sensory analysis data were assessed by calculating average , and perceived percentage of quotes for aroma and flavours , processed in the microsoft excel 2002 .

 table 1 shows the supplement chemical composition used in this study . in its composition , the supplement had high protein value and low carbohydrate content . due to the high content of essential amino acids , especially the branched chain ones , the supplement also showed high nutritional value , as noted in table 2 .
these values are above average when compared to those from other protein sources , for example , casein , soybean , egg , rice , beans , chicken , and so forth , providing supplement with important nutritional properties .
it may contribute to maintain the nutritional status for cd patients , who often require special nutritional support .
due to the wpc amino acids profile , this protein is used to formulate several specialty products , for example , infantile formulas , and for the performance of muscle metabolism , due to the high content of essential amino acids branched chain , for example , leucine and isoleucine .
these characteristics are hugely important for cd patients , due to hypermetabolism and progressive loss of lean mass , with the clinical evolution of the disease .
the results indicated that the supplement has good solubility in a wide ph range ( table 3 ) , which is quite advantageous , since it may be used to formulate various foods , for example , fermented beverages , ice creams , and so forth .
thus , it increases the possibilities for consumption of this supplement with high nutritional value . according to the acceptance averages for aroma , flavour , and viscosity obtained for the cd patients ,
it was observed that the assessment of the supplement in general was between the terms  maybe good or maybe bad  and  just a little good 
46.3% of values were in the region of product rejection ( values from 1 to 4 or between the words 
by contrast , 25.9% of the assessed individuals classified the supplement as  maybe good or maybe bad  and 28% of patients assessed the supplement between  just a little good  and  great  ( values between 6 and 9 on the scale ) ( figure 2 ) .
in fact , the supplement aroma was characterised by presenting the unpleasant aroma notes in percentage of responses , such as soybean / grain ( 31% ) , sour milk ( 17% ) , and cooked food ( 9% ) .
it was observed that a small proportion of quotes were associated with pleasant aromas , for example , sweet / vanilla ( 17% ) . concerning the flavour , the frequency of responses was quite similar to the aroma :
additionally , the flavour was mainly associated with soybean / grain flavour ( 34% of respondents ) , sour milk ( 16% of respondents ) , sweet / vanilla ( 13% ) , and milk powder ( 9% ) ( table 5 ) . for viscosity
, the acceptance was a little better ; nearly 40% liked the sample viscosity against 33% who did not like it .
in general , it was observed that roughly 30% of individuals liked the supplement concerning all attributes assessed . by contrast ,
half of them did not like it and the other , from 20% to 25% , classified it as  maybe good or maybe bad .
 it indicates that the product needs to be improved , especially its aroma and flavour . on the other hand ,
the acceptance was not as bad as the supplement was evaluated only dissolved in water , maybe if the supplement was added to fruit juice or milk drink could have a better acceptance by the patients .
the aroma and flavour of grain / soybean , sour milk , bitter , cheese , cooked food , all noticed by individuals , can be from lipid oxidation or maillard reaction ( or both ) , as some studies have shown .
these reactions contribute to the formation of off - flavours and to the loss of pleasant aromas / flavours of whey - protein concentrate , thus limiting its use .
isolated and identified 43 volatile from wpc , among them several aldehydes , ketones , and hydrocarbons . according to the authors , several of them can contribute to the aromas and flavours perceived in wpc , for example , 2-heptanone , 2-nonanone , 1-octen-3-ol , and volatiles associated with aromas of cardboard , metal , and mould , respectively .  
the formation of volatiles during production and storage of wpc is difficult to control , considering all the reactions that may occur . to obtain a wpc with milder
aroma / flavour would be necessary to standardise the conditions for processing and storage of wpc , and thus obtain a supplement with better sensory quality . despite the low acceptance of the product , 28% of patients indicated that they  probably would buy  the supplement , and
by contrast , 19% of patients indicated that they  perhaps would or would not buy  the supplement , 22% said they  probably would not buy  the product , and 9% of them  definitely would not buy  .  
several studies have demonstrated that complete nutrition with protein supplements improves nutritional status of patients , intestinal inflammation , and , often , recovery of intestinal mucosa .
paradoxically , the treatment using only corticosteroids presents limited effects on the mucosa . in children affected by cd , complete nutrition plays a fundamental role in the increase of their growth , since the additional nutrient provision is coupled with improvement in intestinal inflammation . in cd - acute adults ,
the complete nutrition is greatly effective in relieving the disease and in the nutritional status of individuals , and it can be used together to other therapies to control cd .
therefore , studies assessing and developing oral solutions that are better accepted by patients are very important .
the supplement presented as a good protein source and high content of essential amino acids providing important nutritional properties that can contribute to maintain the nutritional status for cd patients , who often require special nutritional support .
although the supplement was not well accepted for aroma , flavour , and viscosity by most patients , almost 30% of individuals liked the supplement concerning all attributes assessed .
the results indicated that the supplement provided important nutritional properties for patients with cd ; however , for a large number of patients to be encouraged to start the supplementation process , it is essential to improve the sensory quality of the product .   in order to do so , additional research is necessary to prevent the formation of volatiles , which cause off - flavours in wpc , associated in the present study with soybean / grain , sour milk , cooked food , vomit , and other undesirable aromas and flavours .
 the objective of this study was to evaluate the acceptability of an alimentary supplement of bovine whey - protein concentrate ( wpc ) and tgf- , unavailable commercially , by patients with crohn 's disease ( cd ) and determine the chemical composition , solubility , and total amino acids content . 
 the supplement was diluted in water , and an acceptance test was done to evaluate the aroma , flavour , and viscosity of the product using facial hedonic scale ( nine - point scale ) , applied on 54 cd patients . 
 the supplement composition indicated 73.3% protein , 10.5% fat , 2.2% ash , 6.3% water , and 7.7% carbohydrate . 
 the supplement is presented as a good protein source and high content of essential amino acids . 
 the average acceptance for all the attributes was between 5.0 and 6.0 , and the flavour was mainly associated with soybean / grain , sour milk , and sweet / vanilla flavour . 
 the results indicated that the supplement provided important nutritional properties for cd patients ; however , for a large number of individuals to be encouraged to perform supplementation , it is essential to improve the sensory quality of the product . in order to do so 
 , additional research is necessary to prevent the formation of volatiles which cause off - flavours or to mask undesirable aromas / flavours found in it . 
1. Introduction 
2. Material and Methods
3. Results and Discussion
4. Conclusion