Philippine Berry into Jelly, Jam and juice -Part 2

Sensory Evaluation of the Finished Product

The finished food products were evaluated using the laboratory taste method.

Evaluation was done in a well-lighted, quiet and odor free room. Laboratory panelists were asked to sit independently and advised not to communicate with one another.


The samples  were presented in uniformly sized, clean, odorless and tasteless containers. Panelists were served with a glass of wter to rinse their mouth before and after tasting each sample.


The products were evaluated according to the following attributes; color, texture, consistency, smell , flavor and general acceptability using a four point hedonic scale. The following stepers were followed in the evaluation of the sample:

Lipote jam. Five milliliter of processed sample was placed in each uniformly sized coded plastic container and served immediately .

Lipote juice. Twenty five milliliter of juice was placed in each code plastic up and was served immediately.

Lipote jelly. Five milliliter of sample was placed in each uniformly sized plastic container and served immediately.


Determination of Chemical properties

Technical assistance in evaluating the processed products was sought from the Industrial Technology Development Institute (ITDI), Standards and testing division of Department of Science and Technology (DOST) at Bicutan, Taguig.


The samples subjected to testing were all contained in there separate glass jars in the following amounts; 1 liter juice, 1 kilogram jam and 800 grams jelly.


The products were tested as to their total soluble solids (TSS), refractive index, titratable acidity and pH using test method. (AOAC 1995, 16th ed.) Viscosity was also tested using Brookfield  (RVT) Viscometer. The procedures followed in the determination of chemical properties are as follows:


Total soluble solids(Brix)

A refractometer was used to determine the total soluble solids (TSS). A drop of sample (2-3 ml) was placed on the prism of the hand refractometer using a wooden or rubber applicator. Care was taken so that no pulp particles or air bubbles were included. Enough time was allowed for the instrument and the sample temperature to equilibrate. Degree Brix read was equivalent to percent sugar (Askar & Treptow, 1993).


Titratable Acidit (TA)

Titrable acidity was expressed as the amount of free acid  (mainly as anhydrous citric acid) in the product (g/100g, g/100 ml or g/l). Ten ml juice was placed into a 250 ml erlenmeyer flask, then 50 ml water and 5 drops of indicator were added. The mixture was titrated with 0.1 N sodium hydroxide (NaOH) quite rapidly until near pH 6, then the alkali was added slowly to pH 7. Titration was finished by adding 4 drops at at time until  pH 8.1. If no pH meter is available, titrate to the desired end point and faint pink color will occur (Askar and Treptow, 1993)


Measurement of pH value

Twenty five ml of the samples were placed in a 100 ml beaker. The glass electrode was rinsed with distilled water several times. The pH meter was calibrated to pH 7.0 and ph 4.0. The electrode was immersed in the sample container and the pH registered on the digital screen of the calibrated electronic pH meter was read.


Consumer evaluation of the product. A centralize testing system using a Central location Test (CLT) was conducted in the group of respondents from Home Economics, Vocational and Technical Education Department (HEVTED) of the College of Education (CEd) in Cavite State University (CvSU0. One hundred respondents evaluated the processed lipote products. They were made up of students andfaculty members who were purposively selected and asked to taste the samples and describe the level of acceptability according to the prescribed attributes: color, texture, consistency, flavor, aroma, and general acceptability using a four-point hedonic scale.


During the acceptability test, each respondent was given a questionnaire to determine his/her personal characteristics and to elicit information on his/her food and entrepreneurial orientation.

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