Manuscript Title:

EFFECT OF FERMENTATION ON PHYSIOCHEMICAL, STRUCTURAL, RHEOLOGICAL, THERMAL AND PASTING PROFILE OF TARO STARCH

Author:

AYSHA IMTIAZ, RANA MUHAMMAD AADIL, ABID ASLAM MAAN, MUHAMMAD KASHIF IQBAL KHAN

DOI Number:

DOI:10.5281/zenodo.10792430

Published : 2024-03-10

About the author(s)

1. AYSHA IMTIAZ - National Institute of Food Science and Technology, University of Agriculture, Faisalabad, Pakistan.
2. RANA MUHAMMAD AADIL - National Institute of Food Science and Technology, University of Agriculture, Faisalabad, Pakistan.
3. ABID ASLAM MAAN - National Institute of Food Science and Technology, University of Agriculture, Faisalabad, Pakistan.
4. MUHAMMAD KASHIF IQBAL KHAN - National Institute of Food Science and Technology, University of Agriculture, Faisalabad, Pakistan.

Full Text : PDF

Abstract

Starches present manufacturers with novel prospects to produce a diverse range of products characterized by appealing melt-in-mouth textures and robust, unadulterated flavors. The market segment has a growing preference for low-priced starches. The primary aim of modification is to facilitate the restricted utilization of starch across various applications. Lactic acid bacteria specifically Lactobacillus Plantarum are widely employed in the food industry due to their benefits and safety, and also the Food and Drug Administration (FDA) declared them generally recognized as safe (GRAS). The current study evaluated the impact of fermentation on the physicochemical characteristics of taro starch. The impact of fermentation through Lactobacillus Plantarum on samples was studied through dynamic characterization methods, including texture profile analysis (TPA), rapid visco analyzer (RVA), scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), rheometer, and physicochemical analyses. The unfermented samples exhibited a reduced moisture content compared to the fermented ones. The observed rise in moisture content after fermentation can be related to the introduction of water throughout the fermentation process, which facilitates the progression of microbial strains responsible for initiating and sustaining the fermentation process. Consequently, this extended duration of fermentation leads to a constant augmentation in moisture content. Fermentation results in more ash and lower fat and fiber. The protein contents of fermented samples are elevated compared to the nonfermented samples. Bacterial inoculation starts producing some extracellular enzymes known to be proteins. The amylose of fermented samples increases in all samples. The swelling of fermented samples decreased in all samples. Higher amylose results in lower swelling power and solubility attributed to granules’ structural adjustment. Bioconversion of macro-molecules due to fermentation changes the gel structure of starch and decreases the leaching effect, ultimately improving the syneresis. Process stabilization governs product quality, and rheology is the crucial factor in defining the quality of any food. The unfermented samples showed lower rheological characterization as lower loss and storage modulus than the fermented samples. Fermentation results in better viscosity due to the degradation of macromolecules into their building block, which enhances the applicability. Scanning electron microscope concluded a smooth surface for unfermented samples but irregular and sharp edges for fermented samples. This indicates that fermentation results in the degradation of particles, and small particles result in less water retention, while more water absorbing capacity ultimately leads to better rheology and highly compact dough. The FTIR peaks at 3422, 2918, 1570, 1382, 1325, 1162, 1022, 1045 and 765 cm−1 are associated with cellulose. The peak at 3422 cm−1 is attributed to O-H stretching. The absorption at 2918 cm−1 is credited to C-H stretching. A peak at 1570 cm−1 is linked with CH2 symmetric bending. 1382 cm−1 is associated with C-H bending. 1325 cm−1 is associated with CH2 bending of carbohydrates. The peak at 1162 cm−1 is attributed to C-O anti-symmetric stretching. The findings of our study indicate that the comprehensive categorization of starches enhances their practical utility by facilitating a thorough comprehension of their overall profile. The utilization of contemporary methodologies enables enhanced efficiency and heightened precision.


Keywords

Fermentation, Starch, Lactic Acid Bacteria, Modification, Rheology.