Date of Publication
11-28-2025
Document Type
Master's Thesis
Degree Name
Master of Science in Chemistry
Subject Categories
Chemistry
College
College of Science
Department/Unit
Chemistry
Thesis Advisor
Aldrin P. Bonto
Defense Panel Chair
Raymond S. Malabed
Defense Panel Member
Mariafe N. Calingacion
Melfei E. Bungihan
Abstract (English)
Coconut (Cocos nucifera L.) pulp residue is a major by-product of coconut milk extraction which is often underutilized despite its high carbohydrate and lignocellulosic content. This study aimed to optimize solid-state fermentation (SSF) conditions to enhance the soluble protein content of coconut pulp flour and evaluate the resulting effects on its composition and functional properties. Optimization of solid-state fermentation parameter applied a Box–Behnken design with factor including fermentation time (32–96 h), temperature (30–45 °C), and inoculum size (0.5–2.0% v/w) and with soluble protein as the response. The reduced quadratic model predicted optimal conditions of 33.015 °C, 64 h, and 1.752% inoculum, yielding 47.810 mg/g soluble protein. Experimental validation obtained 49.347 mg/g. Under these optimized conditions, fermentation have increased crude protein (17.15%), moisture content (27.25%), and carbohydrate content, with decreases in crude fat (22.28%), crude ash (75.76%), and crude fiber (45.21%). Functional property evaluation also showed enhanced water solubility index (167.84%), oil absorption capacity (5.88%), and water activity (28.66%), but reduced bulk density, water absorption capacity (43.89%), swelling capacity (7.50%), and final viscosity (60.27%). ATR-FTIR analysis indicated notable spectral shifts associated with fats, carbohydrates, and amide group. PCA explained 98.5% of total variance, with PC1 and PC2 accounting for 93.6% and 4.5%, respectively. SEM images showed structural disruption, roughened surfaces, and irregular, fragmented particles to the optimized inoculated coconut flour and phytochemical assays demonstrated increased total phenolic content (81.4%), total flavonoid content (116.9%), and radical scavenging activity (29%). Thermal analyses further supported the enhanced digestibility and structural modification where TGA showed an increased total weight loss, while DSC revealed a lower transition temperature and enthalpy. Overall, the results demonstrated that solid-state fermentation significantly improved the proximate composition and functional properties of coconut pulp flour.
Abstract Format
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Abstract (Filipino)
Ang coconut (Cocos nucifera L.) pulp residue ay isang pangunahing natitirang produkto matapos ang pagkuha ng gata ng niyog na madalas hindi nagagamit nang husto kahit na may mataas itong carbohydrate at iba pang nutrisyon. Layunin ng pag-aaral na ito na malaman ang pinakamainam na mga kondisyon ng solid-state fermentation (SSF) upang mapataas ang soluble protein content ng coconut pulp flour at masuri ang naging epekto nito sa komposisyon at mga katangiang funksiyonal. Ang pag-optimize ng solid-state fermentation na parametro ay isinagawa gamit ang Box–Behnken design na may mga salik na kinabibilangan ng oras ng fermentasyon (32–96 h), temperatura (30–45 °C), at inoculum size (0.5–2.0% v/w), at ginamit ang soluble protein bilang tugon. Ang reduced quadratic model ay nagbigay ng prediksiyon na ang pinakamainam na kondisyon ay 33.015 °C, 64 h, at 1.752% inoculum, na may prediksyon na 47.810 mg/g soluble protein. Sa ginawang beripikasyon, nakuha ang 49.347 mg/g. Sa ilalim ng mga kondisyon na ito, ang fermentasyon ay nagdulot ng pagtaas sa crude protein (17.15%), moisture content (27.25%), at carbohydrate content, at nagdulot naman ng pagbaba sa crude fat (22.28%), crude ash (75.76%), at crude fiber (45.21%). Ipinakita rin ng pagsusuri sa mga katangiang funksiyonal ang pagtaas ng water solubility index (167.84%), oil absorption capacity (5.88%), at water activity (28.66%), ngunit nagkaroon ng pagbaba sa bulk density, water absorption capacity (43.89%), swelling capacity (7.50%), at final viscosity (60.27%). Sa isinagawang pagsusuri gamit ang ATR-FTIR, ipinakita ang mahahalagang pagbabago o pag-shift sa spectra na may kaugnayan sa fats, carbohydrates, at amide group. Naipaliwanag ng PCA ang 98.5% ng kabuuang mga pagbabago, kung saan ang PC1 at PC2 ay may ambag na 93.6% at 4.5%. Ipinakita ng mga imahe sa isinagawang SEM na pagsusuri na nagkaroon ng pagkasira ng estruktura, mas magaspang na ibabaw, at hindi regular at pira-pirasong partikulo sa optimized inoculated coconut flour. Ipinakita rin ng phytochemical assays ang pagtaas sa total phenolic content (81.4%), total flavonoid content (116.9%), at radical scavenging activity (29%). Dagdag pa rito, sinuportahan ng mga pagsusuring thermal ang mas mataas na digestibility at mga pagbabagong istruktural, kung saan ang TGA ay nagpakita ng mas mataas na kabuuang pagbawas ng timbang at ang DSC ay nagpakita ng mas mababang transisyon ng temperatura at enthalpy. Sa kabuuan, ipinakita ng mga resulta na ang solid-state fermentation ay may malaking epekto sa pagpapabuti ng komposisyon at katangiang funksiyonal ng coconut pulp flour.
Abstract Format
html
Language
English
Format
Electronic
Keywords
Solid-state fermentation; Coconut flour
Recommended Citation
Basilla, C. M. (2025). Impact of solid-state fermentation by Rhizopus oligosporus on the composition and physicochemical properties of coconut pulp flour (Cocos nucifera L.). Retrieved from https://animorepository.dlsu.edu.ph/etdm_chem/33
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Embargo Period
12-12-2028
