Edible coatings have long been used to protect food products from microbial contamination and physiological deterioration. Recently, they have gained prominence as eco-friendly alternatives to synthetic and plastic packaging, contributing to reduced postharvest losses. These coatings provide multiple functional benefits, including reducing lipid oxidation, extending shelf life, minimizing moisture loss and protecting against microbial spoilage, thereby improving food quality and safety (Njoku et al., 2025).
       
Polysaccharides, proteins, lipids, or their combinations are the usual sources of biopolymer films used in edible coatings. Additives like plasticizers are added to the film matrix to improve their functionality. Although polysaccharide-based films are clear and have strong mechanical strength, they often have poor moisture barrier qualities (Uzoukwu et al., 2025). By decreasing intermolecular pressures, boosting polymer chain mobility and lowering the glass transition temperature, plasticizers-typically low-molecular-weight hydrophilic compounds-improve film flexibility and handling and reduce brittleness. One of the most popular plasticizers for starch-based biodegradable films is glycerol. Thermoplastic starch, which can be produced using standard methods like extrusion and injection molding, is created when it is mixed with starch under heat and shear. The ratio of starch to glycerol signifiantly influences the mechanical and barrier properties of the resulting films, making formulation optimization essential (Njoku et al., 2026).
       
This study also takes into account breadfruit (Artocarpus altilis), a staple in many tropical locations. It is naturally gluten-free and high in carbs. However, because to lipid oxidation and microbial activity, roasted breadfruit seeds (ukwa) are extremely prone to spoiling, requiring efficient preservation techniques. Edible coatings are applied by dip-coating, a straight forward and affordable method that involves submerging the product in a film solution and letting it dry. Using acha and finger millet starch coatings, this study seeks to increase the shelf life of roasted breadfruit seeds. Moisture content, peroxide value and thiobarbituric acid (TBA) value will be used for evaluation.
       
This study utilizes underexploited cereal crops, finger millet and acha (Digitaria exilis), both rich in starch and nutrients. Finger millet is notable for its high calcium and dietary fiber content, while acha contains a high proportion of starch (60-80%). Despite their nutritional benefits, these grains remain underutilized, although growing awareness of whole-grain health advantages has increased interest in their applications, including edible film production.

Source of Materials: The breadfruit seed were bought at the local market in Ihiagwa, Owerri, Imo State while finger millets seeds were purchased from Rimi Market in Bauchi State’s Toro Local Government Area. Acha (Digitaria exilis)     was bought from the Jos Plateau State market.
       
Place and Duration of Research: The Food Science and Technology Department of FUTO and Pac-Bech Scientific Co. in Owerri, Imo State, provided the chemicals. The work lasted for 18 months, from May 2024 to October 2025.
 
Extraction of starch from finger millet and acha
 
The method of Odimegwu et al., (2024) and Olawuni et al., (2024) was adopted for the extraction starches from millet and Acha seed. After picking the finger millet and Acha to separate the dirt, they were cleaned. The separated seeds (1 kg each) were cleaned and steeped for an entire night at ambient temperature (27°C) in a sodium metabisulphite solution (2 L 1% w/v). A commercial attrition mill was then used to wet grind the hydrated seeds into a slurry after they had been drained and cleaned with clean water. A considerable volume of 1% sodium metabisulphite solution was used to disperse the paste, which was then repeatedly sieved through muslin fabric before the chaff was thrown away. After allowing the suspension to settle, it was separated. The mucilage was scraped off after the supernatant was gently decanted. Until pure starch was obtained, the procedure was repeated multiple times with the mucilage on the starch continuously scrapped (Fig 1). After being sun-dried, the resulting starch was ground up and kept in a sample vial until needed. The processed starch flours from finger millet and acha were shown in Plate 1.




 
Breadfruit seed preparation
 
The methods of Njoku et al., (2025) was used for this process. Fresh breadfruit seeds were sorted for stone, sands, debris and other large particles were removed from the raw sample. The seeds were then roasted in an open heat (mild heat) until the desired firmness was reached. Thereafter the hulls were removed. The seeds where finally stored in air tight containers prior to analysis. Until pure starch was obtained, the procedure was repeated multiple times with the mucilage on the starch continuously scrapped. After being sun-dried, the resulting starch was ground up and kept in a sample vial until needed.
 
Coating solution formation and application
 
The method described by Chinma et al., (2014) was adopted. Acha and finger millet starch blends (100:00, 70:30, 60:40 and 50:50) with 25% glycerol were used to create coating solutions. After weighing out and dissolving a 25% glycerol concentration in distilled water, the composite blends were added to create a coating-forming suspension with a starch concentration of 5% (w/w) of the total water content, regardless of the plasticizer concentration. With pH paper, the coating forming suspension’s pH was brought to 9.98 (with 1 M NaOH).  Samples that were coated were left in an oven to dry. To guarantee a consistent coating on the surface, the samples were dipped three times.
 
Method of analysis
 
The samples (coated and uncoated breadfruit) were stored at ambient conditions (27±1°C) for 27 days. They were analyzed at intervals of 9 days for chemical evaluation (Ofoedum et al., 2026).
 
Moisture content analysis
 
The method of (AOCS, 2006) was used in the determination of percentage moisture content of the coated and uncoated roasted breadfruit (ukwa). The % moisture content at an interval of 9 days was determined and calculated.
 
Determination of peroxide value (PV)
 
Onwuka’s (2018) method was used to determine the peroxide value of both coated and uncoated breadfruit. Simultaneously, a blank test was conducted.
 
Peroxide value (miliequivalent peroxide/ kg oil or fat) =

 
Where;
S = ml of Na₂S₂O₃ (blank correted).
M = Molarity of Na₂S₂O₃ solution.
 
Determination of thiobarbituric acid (TBA)
 
The thiobarbituric acid value was determined as described by Onwuka (2018). TBA was calculated thus:

 
Where;
As = Absorbance of the sample.
Ab = Absorbance of the blank.
M = Weight of the sample.
TBA no (as mg malonaldehyde per kg sample) = 7.8D.
 
Sensory evaluation
 
The approach outlined by Ofoedum et al., (2026) was used. A 9-point hedonic scales were used to score each sensory quality, with 1 denoting extreme dislike and 9 denoting extreme liked.
 
Statistics
 
One-way analysis of variance (ANOVA) was used to assess the collected data. Fisher’s least significant difference (LSD) approach was used to separate the derived means.

The effects of edible coating from acha and finger millet starch blends on the moisture contents of the coated and uncoated bread fruit seed samples stored for 27±1°C
 
The moisture content of coated and uncoated roasted breadfruit seeds increased progressively during storage (Table 1). However, uncoated samples recorded higher moisture uptake (5.265-27.605%) compared to coated samples, indicating the effectiveness of acha-finger millet starch-based edible coatings as moisture barriers. Among the coated samples, the 60:40 (acha:finger millet) blend consistently exhibited the lowest moisture content, followed by 50:50, 70:30 and 100:0 blends. A significant difference (p<0.05) was observed between the 60:40 and 50:50 samples as storage progressed, whereas no significant difference existed between 100:0 and 70:30 at days 0 and 9. The relatively lower moisture content observed in the 50:50 and 60:40 blends may be attributed to improved barrier properties and reduced water vapor permeability, likely due to the formation of denser film matrices in composite coatings, as reported by Chinma et al., (2014). Variations in moisture content across blends may also be linked to compositional differences, particularly the higher amylose content of finger millet compared to acha (Nkama et al., 2000), which enhances film integrity and reduces moisture diffusion.


       
At day 0, moisture content ranged from 5.125-5.265%, with the 60:40 blend recording the lowest value. By day 9, values increased to 16.635-20.18%, while day 18 and day 27 showed further increases (18.48-23.445% and 18.605-27.605%, respectively), with uncoated samples consistently recording the highest values. Moisture content is a critical factor affecting food quality, as higher levels promote microbial growth and spoilage, whereas reduced moisture uptake helps maintain product stability and limit oxidative deterioration.
 
The effect of edible coating from acha and finger millet starch blends on the thiobarbituric acid of the coated and uncoated bread fruit seed samples stored for 27±1°C
 
Table 2 presents the thiobarbituric acid (TBA) values of roasted breadfruit samples over 27 days. TBA measures secondary products of lipid oxidation and serves as an indicator of oxidative rancidity; higher values reflect greater fat deterioration (Monu et al., 2026). The TBA values of all samples increased with storage time, consistent with previous findings on coated nuts (Chinma et al., 2014). However, coated samples consistently showed significantly lower (p≤0.05) TBA values than the uncoated control, indicating reduced lipid oxidation.


       
Throughout storage, TBA values of coated samples remained below 3.00 mg N/100 g, while the uncoated sample increased to 5.12±0.035 mg N/100 g at day 27. At day 0, values ranged from 2.28-2.34 mg N/100 g, with the uncoated sample highest and the 60:40 acha: finger millet sample lowest. By day 9, values increased to 2.65-3.62 mg N/100 g, with the 50:50 blend showing the lowest value. At day 18, values ranged from 1.88-4.06 mg N/100 g, while at day 27, they ranged from 2.86-5.12 mg N/100 g, with the 50:50 blend maintaining the lowest value. Statistical analysis showed significant differences (p≤0.05) among samples, though some blends exhibited no significant differences at specific intervals. The increase in TBA values may be attributed to moisture uptake and lipolytic enzyme activity. Therefore, lower TBA values in coated samples demonstrate the effectiveness of edible coatings in limiting lipid oxidation by acting as barriers to oxygen. The 50:50 and 60:40 blends were most effective, highlighting the influence of coating composition on oxidative stability.
 
The effect of edible coating from acha and finger millet starch blends on the peroxide value of the coated and uncoated bread fruit seed samples stored for 27±1°C  
 
Peroxide value (PV) is mostly used to assess rancidity development in fatty foods. The increase in PV of fatty foods over a specific storage time usually indicates the extent of direct contact with air/oxygen. A rancid taste often becomes noticeable at a peroxide level of 10%-20% (Oparaku et al., 2010). The peroxide values of the coated and uncoated samples were shown in Table 1 below. Their PV were low throughout the storage time (in the range of 0.035-0.17).  This indicates a good preservation status for the samples and the likeliness of their fat components becoming rancid is low. The low PV can be attributed to the processing method adopted for the sample preparation. The high temperature treatment during roasting usually reduces PV and increases oxidative stability (Akinoso et al., 2010; Ofoedum et al., 2025 and Ofoedum et al., 2024).
       
The PV of the samples increased slightly between 0.035 and 0.04 to a range between “0.095 to 0.17” after 27 days. There was a significant difference in the PV of the samples only at 9-18 days. The samples showed no significant difference in their PV at 27 days.
       
All samples’ peroxide values rose over the course of the 27-day storage period, as shown in Table 3. Compared to the uncoated samples, the coated samples’ peroxide value increased far less. These findings are consistent with those of Ofoedum et al., (2025), who coated peanuts with a carboxymethyl cellulose (CMC) coating that contained gum cordia and whey protein, respectively and showed how the coating affected the decrease in PV.


       
The peroxide value of the individual samples at day 0 ranged between 0.035-0.040 Meqv/kg. All samples’ peroxide values did not differ from one another significantly (p≤0.05).
       
The peroxide value of the various samples at day 9 ranged between 0.060-0.095 Meqv/kg, Sample 100:00 and uncoated having the lowest and the highest values respectively. The peroxide value of all samples were significantly different (p≤0.05) from each other except sample70:30 and 60:40.
       
The peroxide value of the various samples at day 18 ranged between 0.07-0.14Meqv/kg, Sample 60:40 and uncoated having the lowest and the highest values respectively. The peroxide value of all samples were significantly different (p≤0.05) from each other.
       
The peroxide value of the various samples at day 27 ranged between 0.09- 0.1 Meqv/kg, the peroxide value of all samples were not different significantly (p≥0.05) from each other.
       
This showed that acha: finger millet edible coating were effective in delaying oxidative deterioration in roasted breadfruit seed during ambient storage. However, the low peroxide values of roasted breadfruit seed may be attributed to low moisture sorption characteristics of the seeds due to its strong barrier effect (Chinma et al., 2014).
 
The effect of edible coating from acha and finger millet starch blends on the taste of the coated and uncoated bread fruit seed samples stored for 27±1°C
 
The effect of edible coating on taste is presented in the above Table 4. The taste of coated and uncoated sample decreased with storage time. The result for the taste showed that the taste of roasted breadfruit where appreciated until the 18day of storage when it developed and objectionable taste. A significant difference (p<0.05) exist between the samples as the day progressed except for sample 50:50 and uncoated sample that was not significantly different (p>0.05) on day 9 and day 18, same as sample 60: 40 on day 18 and 27.


       
The taste value of the various samples at day 0 ranged between (8.23-8.62) with sample 50:50 and 60:40 having the lowest and better taste respectively. A significant difference does not exist (p>0.05) between the uncoated sample, 100:00 and 70:30 samples but a significant difference (p<0.05) exist between sample 60:40 and 50:50.
       
The taste value of the various samples at day 27 ranged between 3.66 and 5.87 with the uncoated and sample 60:40 having the least and better taste respectively. There was a significant difference (p<0.05) among all the samples.

Researchers have mentioned that the presence of an edible coating based on proteins and polysaccharides does not alter either the natural taste or texture of food (Chinma et al., 2014).
 
The effect of edible coating from acha and finger millet starch blends on the aroma of the coated and uncoated bread fruit seed samples stored for 27±1°C
 
The effect of the edible coating on the aroma of the coated and uncoated sample are seen above in Table 4. The aroma of the uncoated and coated sample decreased with storage time. There was a significant difference (p<0.05) in the aroma of the roasted breadfruit seed. With respect to the uncoated and coated samples, the uncoated sample had a higher value for day 0 compared to other coated samples and there is a significant difference (p<0.05) among the sample in day 0. The aroma of the uncoated sample depreciated significantly (p<0.05) after day 0. Sample 60:40 had a better aroma at the end of the storage period compared to other coated samples.
       
The reduction in sensory scores of uncoated roasted breadfruit seed with storage time could be attributed to onset of rancidity. These observations in sensory attributes were consistent with earlier reports by Nkama (2000) who reported that coating of food materials improved their color, flavor, crunchiness and overall acceptability.
 
The effect of edible coating from acha and finger millet starch blends on the texture of the coated and uncoated bread fruit seed samples stored for 27±1°C
 
The effects of the edible coatings on the texture of the coated and uncoated sample are seen above in Table 4. The texture of the coated and uncoated sample decreased with storage time. Texture is another important quality determinant of breadfruit seed that characterizes crispiness and crunchiness (Wilkinson et al., 2000). Differences in the sensory attributes between the coated samples and uncoated controls could be attributed to the barrier effect caused by acha and finger millet edible coating.
       
The control sample at day 0 had a better texture compared to the coated samples but as the days of storage increased, the value for the uncoated sample reduced compared to the coated samples. This could be as a result of absorption of moisture in the uncoated samples as edible coating serves as a barrier to moisture thereby improving its crispiness (Wilkinson et al., 2000). A significant difference exist (p<0.05) among the various samples and as the storage days increased.
 
The effect of edible coating from acha and finger millet starch blends on the color of the coated and uncoated bread fruit seed samples stored for 27±1°C 
 
The effect of the edible coating on the color of the coated and uncoated sample are seen above in Table 4. The texture of the uncoated and coated sample decreased with storage time. Sample 60:40 had the best color among all the samples (8.87-6.36) while sample 70:30 had the least (7.96-6.83) and the day progressed. There was a significant difference (p<0.05) in the days and among the samples.
       
Color and texture change during storage of roasted breadfruit seed is one of the major determinants of consumer acceptability. In addition to consumer acceptability, color is also used for quality control (Nkama 2000).
 
The effect of edible coating from acha and finger millet starch blends on the general acceptability of the coated and uncoated bread fruit seed samples stored for 27±1°C
 
The results on the sensory evaluation of the overall acceptability is shown in Table 4. The result shows that the acceptability of the uncoated sample decreased from 6.98 -4.46 during the 27day of storage, similarly, the acceptability of the coated samples decreased to 5.76 after 27 days. The uncoated sample had the least value and sample 50:50 had the highest acceptability value. A significant different (p<0.05) exist between all the samples, the very low acceptability noticed on the uncoated samples may be as result of onset of rancidity and higher moisture uptake (Monu et al., 2026).

The study has been able to provide scientific information on the shelf-life extension of roasted breadfruit seed using acha and finger millet composite starch based edible coating stored for 27 days at interval of 9 days. The edible coating from acha and finger millet starch blend was able to extend the shelf-life of the roasted breadfruit seeds for 27 days without any noticeable change in the quality or deterioration by lipid oxidation. Among the studied acha and finger millet starch blend edible coatings, the 60:40 (acha: finger millet) edible coating extended the shelf life of the roasted breadfruit seed for 27 days at ± 1°C ambient temperature with the lowest moisture content, peroxide value and thiobarbituric acid value. The ability of the edible coating from acha and finger millet starch blend to extend the shelf life of roasted breadfruit seed adds value to these underutilized cereals and establishes their potential for use in food industries and would greatly enhance the utilization of the roasted seeds.
       
To fully utilize the potential of the edible coating from acha and finger millet starch blends in the shelf-life of common snacks and fruits such as the roasted breadfruit seed studied, it is recommended that; further research be carried out to ascertain the microbial quality of the coated food products during the storage time. This is to ensure that microorganisms that could survive in an anaerobic condition were eliminated. The storage time may be further extended and observed for any noticeable change in quality during storage. Due to time constraints, this study could not project the maximum storage time for the coated breadfruit nut.

The co-operations of all the staff of the Department of Food Science and Technology, Federal University of Technology, Owerri are hereby acknowledged.
 
Disclaimers
 
The views and conclusions expressed in this article are solely those of the authors and do not necessarily represent the views of their affiliated institutions. The authors are responsible for the accuracy and completeness of the information provided, but do not accept any liability for any direct or indirect losses resulting from the use of this content.
 
Informed consent
 
All procedures for experiments were approved by the committee of experimental and handling techniques and University Technicians and Scientists.

The authors declare that there are no conflicts of interest regarding the publication of this article. No funding or sponsorship influenced the design of the study, data collection, analysis, decision to publish, or preparation of the manuscript.