CONSUMER ACCEPTANCE TESTING PROCESSED FLORIDA BLUEBERRIES

Transcription

1 260 FLORIDA STATE HORTICULTURAL SOCIETY, 1974 While there might be relativel minor ear-toear variations in berr characteristics, the data presented here indicate that several of these tetraploid blueberr selections bear fruit of sufficientl high qualit as to be commerciall acceptable. Rat ings on productivit, disease resistance, and good horticultural bush characters are being determined before an of the cultivar selections are chosen for release to the public. Literature Cited 1. Knapp, F. W Processing evaluation of Florida blueberries. Proc. Fla. State Hort. Soc. 84: Knapp, F. W., and Sherman, W. B. Consumer ac ceptance testing of processed Florida blueberries. Proc. Fla. State Hort. Soc. 87: 3. Noether, G. G "Non Parametric Statistics". John Wile and Sons, New York. p. 54. CONSUMER ACCEPTANCE TESTING OF PROCESSED FLORIDA BLUEBERRIES F. W. Knapp IF AS Food Science Department Gainesville W. B. Sherman I FAS Fruit Crops Department Gainesville Abstract This stud was the culmination of an investigation of the suitabilit of Florida grown rabbitee blueberries for commercial processing. Fruit (cultivars Woodard, Southland and Bluegem) were processed into blueberr perserves and pie filling in the Food Science Department pilot plaift. Samples of each of these products were paired with corresponding commercial samples and submitted to randoml selected consumer panels to be rated for acceptabilit. There was little difference between scores for pie fillings. Although the Florida preserves were well recived, the commercial preserves were preferred b of the panelists. Nevertheless it must be concluded that these rabbitee blueberries have considerable potential for processing. fillings were at least equal in acceptance to the corresponding commercial products. The general order of cultivar preference was Southland (S), Bluegem (B), Tifblue (T) and Delite (D), al though the differences in ratings were not alwas significant. Besides the above named cultivars, it was desired to test the acceptabilit of processed Woodard (W) fruit. While the results of these limited sensor com parisons were encouraging, preparation of products on a semi-commercial scale and evaluation b a larger number of consumers would be necessar in order to authenticate an general statements as to the relative acceptabilit of the northern and southern blueberr products. In order to eliminate an bias due to differences in freshness of products, for the large scale con sumer panel in 1974, the processors of brand K pie filling and brand X preserves kindl agreed to furnish samples from their current production. Formulations of Florida products were as close as possible to those of the commercial products; how ever, there were slight but perceptible differences in sweetness and tartness. Introduction A previous paper (2) reported preliminar comparisons of the processed qualit of Florida grown rabbitee blueberries (Vaccinium ashei Reade) with that of the northern highbush blue berr products currentl being distributed. At that time, limited preference te>sts with laborator pan els indicated that the rabbitee preserves and pie.florida Agricultural Experiment Stations Journal Series No Materials and Methods In June 1971, 20 pounds each of D. T, S, B, and W rabbitee blueberries were obtained after overnight storage at 5C and were immediatel frozen. After 3-6 mos. storage at 30C, the were made into preserves and pie fillings as previousl reported (2). In the autumn of 1971, brand X commercial preserves and brand L pie fillings, ob tained from local markets, were compared to cor responding products made from each of the 5

2 KNAPP & SHERMAN: ACCEPTANCE OF PROCESSED BLUEBERRIES 261 rabbitee cultivars. A balanced incomplete block design was used; 15 judges compared a different set of 4 samples with a reference (T) on each of 2 das. Scoring and data analsis were carried out as previousl described (2). In a larger experiment, blueberr pie fillings were served to 117 judges in their own work areas on the Universit of Florida campus, with each receiving a B sample flanked b 2 samples of brand L. Similarl, 140 panelists were presented with S pie filling and 2 flanking samples of brand L. Data were subjected to Z test (3). In June 1974, 10.5 kg of rabbitee blueberries consisting of approximatel equal portions of W, S and B fruit, grown at the Horticulture Unit, Gainesville, were held overnight at 2C, washed and sorted. A 150 g composite sample of the berries had a ph of 3.2 and 11.7% soluble solids b refractometer. Pie filling formulation was as before, but cooking was carried out in a steam kettle in the Food Science Department pilot plant. The product was hot filled at about 98C, into steam sterilized, enamel lined 303 cans, sealed in an automatic can sealer and cooled 15 min under run ning tap water; ield, 33 cans. In October the rabbitee and brand K pie fillings (the latter from processor's current production) were baked into large rectangular pies (with top and bottom crusts) and served to 259 panelists, each of whom was presented a 2 sq inch piece of each pie (coded) on a paper plate, with a fork, and asked to give an acceptance rating for each sample. A 9-point facial hedonic scale (1) was used; extreme dis pleasure was scored as 1 and extreme pleasure as 9. Positions of the 2 samples were reversed mid wa through each panel session, both on the serv ing plate and on the score sheet. In addition to checking the rating scale, each participant was asked to circle a statement as to age group (15-25, 26-35, 36-50, over 50), sex and frequenc of use of the product (dail, once a week, once a month, seldom, if ever). Another 10 kg of equall mixed B, W and S berries from a commercial planting at Melrose, FL, Table 1. Laborator panel hedonic scores1 berr products (1971). for blue- Sample W B D X K Preserves scores 5.7a 5.7a 5,65a 5.36ab 5.05ab 4.6b Pie filling scores 5.12z 5.31z 5.38z 5.13z 5.16z 4.37z 2 Scores followed b the same letter are not different b Duncan's test, 5% level. Sample identification is explained in text.

3 262 FLORIDA STATE HORTICULTURAL SOCIETY, 1974 (ph 3.0, 14.5% soluble solids) were processed into preserves (2) in a steam kettle, hot filled into sterilized quart Mason jars, and vacuum sealed. The ield was 19 quarts, ph 3.2, soluble solids 66.5%. In preparation for sensor evaluation these preserves and brand X preserves from proc essor's current production were placed in coded 3/4 oz Lill-Tulip plastic creamer cups and covered with paper lids. Each participant received the 2 coded samples, two unsalted-top soda crackers and a plastic knife. The same kind of score sheet was used as for the pie fillings, and position of the 2 samples on plate and score sheet was reversed mid wa through the session. The sensor results reported here were ob tained at the colonnade of the J. Wane Reitz Student Union on the Universit of Florida campus, where 259 pairs of pie samples were tasted one afternoon and 423 pairs of preserves samples were judged during 2 afternoons. Data from these paired difference tests was analzed for significance using Student's t test. Table 2 shows that the mean hedonic scores as given b the 1971 consumer panels were not sig nificantl different for left or right position of the commercial samples. There was no difference in acceptance between the B and L pie fillings. How ever, S was judged superior to L (P <.05). The results of the 1974 consumer panels are presented in Table 3. Among the judges of pie fillings there were few age or frequenc of use groups which expressed a definite preference for either sample. Of the 259 pie filling panelists, 116 scored K higher, 126 scored (49%) the Florida product (F) higher, and 17 gave them equal rat ings. B contrast, of the 423 persons who tasted blueberr preserves rated brand X higher than F. The mean scores (7.71 and 6.74, respectivel) were different at the level of significance. Among males it was the oungest age group and the oncea-week jam users which rated brand X most highl over F. In addition, 8 of 9 males over 50 preferred X over F b average scores of 8.78 to 6.67, respectivel. Among the females, all fre quenc of use groups preferred X over F (P <.05 Table 2. Mean hedonic scores for commercial and two rabbitee blueberr pie fillings (1971). Sample' No. of Judges L B k 5.26k 4.97k a 5.07b 4.56a 2 Scores followed b the same letter are not dif ferent b Z test (3), 5% level. Duplicate samples of commercial sample (L) were placed to left and right of Bluegem (B) or South land (S) pie fillings-

4 KNAPP & SHERMAN: ACCEPTANCE OF PROCESSED BLUEBERRIES 263 Table 3. Sensor ratings of blueberr products (1974). k. Pie fillings according to sex of panelists. Sex z No. Mean Scores2 F > K k" F 84 ot 7 /.zu NS 50% M NS 47% M+F Q ?/, NS hc 49^ B. Preserves according to sex of panelists, age group and fre quenc of use. X F P <x X > F F M F+M % 63% > NS NS 67% 54% 71% Dail Weekl Monthl Seldom, if ever % 65% 57% z Mean hedonic ratings obtained b paired comparisons. Sample identification is explained in text. F > K refers to percent of panelists rating F higher than K. P < indicates level of significance of mean differences as deter mined b t test.

5 264 FLORIDA STATE HORTICULTURAL SOCIETY, 1974 for the dail use group and P < for other groups). The age group included 146 out of the 165 total females and of these 105 (72%) pre ferred X over F preserves. Although there were several groups of individuals 26 ears and older which did not ield a significantl different score for either product, there was no instance of a higher rating for F. The above data suggest that rabbitee berries are equal if not superior to highbush blueberries for making pie fillings, but inferior for preserves. Other factors should be considered. No accurate record was kept of verbal comments about the products, but frequent panelists remarked about the undesirable (to them) sweetness and/or acidit of the F preserves. The latter reflects the some what lower ph (3.15) of that product compared to brand X (ph 3.3) and is a function of the amount of acid used in adjusting the ph. Although total solids b refractometer were actuall lower in the F preserves than in brand X (66.5% vs 67.8% respectivel) part of the sucrose in the latter had been replaced b corn srup, which would prob abl provide less sweetness than an equal quantit of sucrose. Several individuals declared the F sample to have a truer blueberr flavor; more said the same of brand X. It should also be noted (Table 3) that over 75% of the preserves judges were ears old, the group which gave the largest mean dif ference between scores (P < ). The older panel ists were less emphatic about their preference and although a majorit preferred X over F, the dif ferences in ratings between the two became less significant as the age of the judges increased (P <.05 for and not significant for the older groups). Also the dail users of jams and preserves were more moderate in their scoring of X over F pre serves than the less frequent users were. The dail users mean score difference was onl sig nificant at the 5% level. The once a week group led the less frequent users in recording greater differences (P < ) in ratings of the 2 preserves samples. Data obtained from subsequent consumer pan els, containing a larger proportion of older per sons, should help to resolve some of these ques tions especiall if more judges who are familiar with jams and preserves through dail use are also included. Even accepting the panel results at face value it must be noted that a mean score of 6.7 on a 9-point scale signifies a rating just below "like moderatel" and substantiall above an degree of dislike. The conclusion to be drawn from this stud is that from the point of view of fruit qualit, Flor ida grown rabbitee blueberries have considerable potential for processing. Man other economic and horticultural factors must be met before a blue berr growing and processing industr can become viable in the state. Literature Cited 1. Ellis, B. H Preference testing methodolog, Part I. Food Technol. 22: Knapp, F. W Processing evaluation of Florida blueberries. Proc. Fla. State Hort. Soc. 84: Steel, R. G. D., and Torrie, J. H Principles and Procedures of Statistics. McGraw-Hill. New York, p. 40.