Status : Verified
| Personal Name | Usero, Joanna Marie Carla L. |
|---|---|
| Resource Title | Quantification of the Influences of Product and Process Variables on Ascorbic Acid Concentration and Color Changes in Heat-Treated Lemon Juice |
| Date Issued | 31 June 2015 |
| Abstract | The study established response surface models to quantify the effects of product (pH and initial ascorbic acid concentration,AAi) and process variables (temperature, T and time, t) on residual ascorbic acid concentration (rAA) and percentage ascorbic acid reduction (%AAr) in heated simulated fruit juice (SFJ)systems. Moreover, the effects of SS, dilution (%H20), temperature and time on the Commission Internationale de l'Eclairage (CIE) measured (L*, a*, b*, ΔL*, Δa*, Δb*) and derived (C*, ΔC*, h°, Δh°, ΔE*) color parameters of heated lemon juice samples were also quantified through response surface modeling. A Central Composite Rotatable Design of experiment was employed to determine the combinations of the product and process variables tested. According to the results of the analysis of variance (ANOVA), T, t, and AAi significantly influenced rAA while T, t, AAi, T^2 (quadratic effect of T), and AAi^2 significantly influenced %AAr. On the other hand, L* and ΔL* were significantly influenced by SS, %H20, and T^2 while a* and Δa* were significantly influenced by T, SS, %H20, Tx%H20^2 were found to significantly influence b*, Δb*, C*, and ΔC*. ANOVA results also showed that ΔE* was significantly influenced by SS, %H20, SS^2, and %H20^2 while h° and Δh° were significantly influenced by T, SS, %H20, T^2, SS^2, and %H20^2. Validation of the predictive models for rAA and %AAr, resulted in an acceptable model predictive performance with all the 15 validation points having Af< 1.60. Furthermore, model validation for the CIE color parameters revealed that 84.54% (93 out of 110 points) of the total predictions are within the acceptable range. The models established in this study may be used in the design of thermal processing schedules that account for both the safety and quality of food products. |
| Degree Course | Bachelor of Science in Food Technology |
| Language | English |
| Keyword | Lemon juice--Processing--Mathematical model |
| Material Type | Thesis/Dissertation |
Preliminary Pages
1.27 Mb
Category : P - Author wishes to publish the work personally.
Access Permission : Limited Access