Mold Counts Research Articles

Microbiological Quality Assessment of Meatball Samples Collected from Businesses with Different Pricing Strategies

Objective: The purpose of this study was to evaluate the microbiological quality of meatball samples collected from establishments employing different pricing strategies. Materials and Methods: Samples were obtained from low-priced establishments (Business I) and high-priced establishments (Business II) and were analyzed for total aerobic mesophilic bacteria (TAMB), yeasts and molds, coliform bacteria, Staphylococcus aureus, Escherichia coli, Salmonella spp., and Listeria monocytogenes. Results: Both groups of samples complied with Turkish Food Codex standards for TAMB and S. aureus, while yeast and mold count in Business I samples exceeded the permissible limits. Salmonella spp. was detected in 3.3% of the samples from Business I and 6.6% from Business II, whereas L. monocytogenes was not detected in any of the samples. Conclusion: The study findings showed that there was no significant difference in microbiological quality between the two groups, except for yeast and mold counts. It was also concluded that there was no direct relationship between product price and hygienic quality. Keywords: Food pricing strategies, Hygienic quality, Meatball, Microbiological quality

Investigation Growth and Survival Of Some Pathogens In Koumiss

The aim of this study was to investigate the growth and survival of Escherichia coli O157:H7, Listeria monocytogenes and Staphylococcus aureus in koumiss produced from raw mare's milk during the fermentation process. E. coli O157:H7 (Group 1), L. monocytogenes (Group 2) and S. aureus (Group 3) were added to the raw mare’s milk that would used to producing koumiss and a combination of all three pathogens (Group 4) was inoculated. These microorganisms were introduced at 106 cfu/ml concentration into the raw mare’s milk, which served as the base for koumiss production. During fermentation, microbiological and chemical analyses were carried out by taking one sample from each group at the 1st, 5th and 24th hours and at the 2nd, 3rd, 4th and 5th days. As a result of analyzes; pH, dry matter, and protein content declined, while titration acidity and alcohol content increased. A positive correlation was found between the bacterial count and the utilized pathogenic microorganisms. Conversely, a negative correlation was observed with the count of yeast molds. Remarkably, the counts of E. coli O157:H7, L. monocytogenes, and S. aureus reduced starting from the fifth hour of fermentation and diminished to undetectable levels by the second day. This decline in pathogenic microorganisms below detectable thresholds during the fermentation process was linked to the rise in titration acidity and alcohol content and the decrease in pH.

Effect of the Storage Conditions on the Microbiological Quality and Selected Bioactive Compound Content in Fruit Mousses for Infants and Young Children

Fruit mousses, as low-processed products, are highly susceptible to external conditions, and storage leads to the degradation of bioactive compounds, particularly phenolic compounds and vitamins, as well as promoting the growth of yeasts and molds. This study investigated the impact of storage conditions on the microbiological quality and degradation of selected bioactive compounds in fruit mousses from various producers (from apples, pears, and multi-components). Total phenolic (TPC) and total flavonoid (TFC) contents, vitamin C level, antioxidant capacity (AC, measured by the DPPH assay), and concentrations of macro- and microminerals were evaluated in fresh mousses and those stored for 48 h at 23 °C and 4 °C. Changes in total aerobic mesophilic bacteria (TAMB), yeast and mold counts, and selected microbial groups were also checked. It was found that the analyzed compounds varied depending on the components of the mousses. Multi-component mousses contained the highest levels of TPC, TFC, and vitamin C, and had 2–5 times higher AC values compared to apple and pear mousses. Storage at room temperature resulted in TFC lowering of up to 25% in apple mousses and vitamin C reductions of up to 22% in multi-component mousses. During refrigerated storage, the highest losses were observed in pear mousses, with TPC decreasing by up to 13% and vitamin C by up to 11%. Among the minerals, magnesium and zinc levels decreased most significantly in apple mousses stored at 23 °C (up to 33% and up to 29%, respectively). Microbiological analysis revealed variability in TAMB, yeast, and mold counts, with refrigeration (4 °C) generally limiting microbial growth compared to room temperature (23 °C). Notably, no pathogenic bacteria were detected under any storage conditions, and the mousses retained a high microbiological quality even after room-temperature storage.

Impact of climate and traditional practice on quality of homemade dahi.

This research communication aimed at assessing the microbial quality and preparation practices of dahi/thayir, a popular traditional fermented milk product, in households from two distinct agroecological zones in Kerala, India, namely the high-range and central midland, We highlighted the significant variations and potential food safety concerns associated with regional differences in production methods. The local climate significantly influenced the incubation temperature of dahi/thayir, thereby influencing the types of microflora involved in the fermentation process. Data on preparation practices and sensory preferences were collected from producers during the sampling process, covering 200 households. There were significant variations in preparation practices between the two regions, particularly concerning the type of container used, inoculation rate and incubation period. Samples from the high-range region exhibited significantly higher acidity and coliform count as well as yeast and mold count than the central midland region. The household fermentation of milk is often uncontrolled, causing increased acidity levels. This uncontrolled fermentation favored the growth of contaminants such as coliforms and yeast, posing a potential threat to food safety. This study underscores the importance of understanding microbial quality variations and preparation practices in dahi/thayir production, emphasizing the need for proper fermentation techniques and hygienic practices to ensure the safety and quality of this traditional fermented milk product.

A Novel Green Tea Extract-Loaded Nanofiber Coating for Kiwi Fruit: Improved Microbial Stability and Nutritional Quality

This study investigated the use of green tea extract (GTE)-loaded PVA-based nanofibers for preserving fresh-cut kiwi fruit. Scanning Electron Microscopy (SEM) images confirmed that the nanofibers were smooth, uniform, and free from significant defects, with a consistent diameter ranging from 100 to 300 nm. Significant reductions in the total mesophilic aerobic bacteria (TMAB) and yeast and mold counts (TMY) were obtained. On the last day of storage, the TMAB in GTE-coated samples was 1.75 log CFU/g lower than uncoated samples, and the TMY was 2.25 log CFU/g lower (3.50 vs. 5.75 log CFU/g). The kiwi fruit that were coated with nanofibers had higher antioxidant activity, better vitamin C retention (32.3 mg/100 g on day 10 vs. 22.9 mg/100 g for controls), and lower malondialdehyde (MDA) levels (25.3 nmol/kg on day 10 vs. 49.2 nmol/kg for controls), which meant they had less lipid peroxidation and oxidative stress, resulting in improved cellular integrity and extended product shelf life. These findings suggested that GTE-loaded nanofibers could effectively enhance the microbial stability and nutritional quality of fresh-cut kiwi fruit. This study highlighted the potential of using bioactive substance-loaded nanofibers as a novel and effective preservation method for fresh produce, with significant implications for the food industry.

Investigating the effect of combined radiofrequency cold plasma (RF-CP) treatment on techno-functional attributes of Cashewnut

In the realm of food safety, dried foods often find themselves on the favourable side of the risk spectrum, enjoying the reputation of being relatively safer. However, dried food products are reportedly contaminated by microorganism beyond permissible limits, thus, depleting their quality, shelf-life, etc. and pose a threat to the consumers. This study aims to explore the effect of radiofrequency low-pressure cold plasma (RF-CP) processing on cashew nuts, using four gas combinations: Nitrogen (N2), Argon (Ar), N2+O2, and Ar+O2. Dried cashew nut kernels underwent RF-CP treatment at six different power options (60, 90, 120, 150, 180, and 210 W), at four distinct time (5, 10, 15, and 20 min). Following the treatment, the samples underwent proximate analysis, microbial load reduction, sensory analysis, peroxide value, and texture analysis. The findings exhibited a direct relationship between plasma power and treatment duration, indicating that an escalation in both parameters induced proportional enhancement in the reduction rate of microbes, with a maximum reduction of over 99% in total plate count, yeast and mould count at 120 W for 20 min and 150 W for 15 min for N2+O2 and Ar+O2 gas combinations, respectively. No statistically significant difference was observed in the sensory, nutritional, and peroxide value between the treated and untreated samples (p > 0.05). However, the moisture content of treated sample decreased, and firmness increased with an increase of power and RF-CP exposure time. This research demonstrates the feasibility of using RF-CP to decontaminate cashews by inactivating microbes, extending shelf life, and altering surface properties, which may enhance texture and appearance. However, it may also induce oxidative changes in lipids and proteins, potentially affecting flavor, nutritional quality, and allergenicity. It is an emerging and alternative to high-temperature processing for disinfecting products like nuts, spices, aromatic plants, and other delicate and luxurious foods.

Efficiency of Potato Peel Extract in the Preservation of Cow Butter

This study investigates that the phenolic compound extracted from the potato peels using ethanol by maceration as a natural preservation agent for cow butter, yielding 10.42 ± 0.03% phenolic compound. A quantitative and qualitative analysis of potato peels extract (PPE) was conducted to examine the phenolic compounds. The major preliminary phytochemical screenings (Alkaline Reagent Test, Ferric Chloride Test, Chloride Test) were performed to detect the presence of phenols, flavonoids, and tannins. The total phenolic content was measured using the Folin–Ciocalteu method with UV spectrophotometry, which produced 2.9468 ± 0.03 mg GAE/g of dry extract. The total flavonoid content was determined using the aluminum chloride colorimetric method, resulting in 3.6885 ± 0.02 mg equivalent Quercetin/g of dry extract. During 21 days, butter samples treated with PPE at various concentrations (0.2% and 0.3%) and storage temperatures (20 °C and 45 °C) were examined for chemical parameters (peroxide value and free fatty acid value) and microbiological parameters (aerobic total bacterial count and yeast mould count). The findings showed that the samples preserved at 20 °C with a concentration of 0.3% extract had better preservation than samples stored at other temperatures. It also showed lower values of peroxide and free fatty acids, as well as less microbial growth. On the other hand, samples without extract that were kept at 45 °C demonstrated more oxidation and microbial growth. The oxidative stability of cow butter was assessed using the Rancimat method. Results indicate that PPE significantly enhances both oxidative stability and shelf life, offering preservative benefits for up to six months. Specifically, the induction period (IP) at room temperature reached 3,960 hours (165 days) with PPE, compared to only 120 hours (5 days) without it. These findings suggest that the phenolic compounds in the potato peels could serve as natural preservatives for cow butter, particularly when stored at lower temperatures.

BURONG TILAPIA: FACTORS ON THE FERMENTATION PROCESS AND ITS MICROBIOTA

Fermented fish products hold significant prominence in the Philippines. However, its potential risks for human consumption are faced as a result of inadequate awareness of microbiological standards in its preparation. This study investigated the microbiota and fermentation process of burong tilapia, how this is influenced by fermentation factors such as salt content, temperature, and proper sanitation, and how it can impact food safety for human consumption. This study revealed that the population of aerobic microorganisms in burong tilapia was relatively high with the Aerobic Plate Count result of 2.1 x 107 CFU/g, indicating significant bacterial presence. On the other hand, a relatively low level of E. coli and Yeast and Molds count was detected having <25 CFU/g and <10 CFU/g, respectively. Moreover, it was found that low salt content, non-ideal temperature conditions and failure to strictly observe sanitation practices, all influenced the growth and proliferation of unwanted microorganisms. These results emphasize how crucial it is to optimize fermentation factors in order to guarantee both the food quality and safety of fermented fish products for human consumption. Furthermore, this case study highlights that consumer education is needed in promoting awareness and acceptance of fermented fish products in the market.

Innovation of tempeh from jack bean (Canavalia ensiformis) fermented with Mosaccha inoculum

Tempeh is a traditional Indonesian food made from soybeans fermented with Rhizopus oligosporus. The development of tempeh from jack beans fermented with a tempeh starter containing a combination of Rhizopus oligosporus and Saccharomyces cerevisiae (Mosaccha inoculum) represents a new innovation. This study aims to evaluate the influence of Mosaccha inoculum on the microbiological and sensory properties of jack bean tempeh. The experiment was designed using a Completely Randomized Block Design with a single factor at six levels, each repeated four times: 0.2% Mosaccha inoculum, 0.4%, 0.6%, 0.8%, 1%, and Raprima 0.5% as the control. The best jack bean tempeh was further analyzed for its nutritional content, HCN levels, and β-glucan content. The results showed that the addition of 0.6% Mosaccha inoculum produced the highest quality jack bean tempeh. This tempeh had a characteristic tempeh aroma with a slight yeast scent, a white color, evenly distributed mycelium growth, and a firm texture that did not easily crumble. Based on sensory evaluation, the taste and overall acceptability of this tempeh were well-liked. The best jack bean tempeh had a moisture content of 58.72%, total mold count of 7.58 log CFU/g, total yeast count of 8.99 log CFU/g, protein content of 15.83%, fat content of 10.92%, ash content of 1.14%, crude fiber content of 0.89%, HCN content of 2.47 ppm, and β-glucan content of 0.904%. This study demonstrates that jack bean tempeh produced with a 0.6% Mosaccha inoculum concentration offers a high-quality and nutritionally valuable alternative to traditional tempeh.

Physicochemical and microbiological evaluation of yoghurt sold in Addis Ababa, Ethiopia

BackgroundIncrease in demand for yoghurt in Addis Ababa, in recent times has led to proliferation of different kinds of commercially produced (branded) yoghurt in line with the traditional (unbranded) one in the market. However, limited or no available data for the quality of gradually increasing different kinds of commercially produced (branded) yoghurt in line with the traditional (unbranded) one in the market. It was therefore vital to evaluate the physicochemical property and microbial quality of yoghurt sold in Addis Ababa in order to determine its quality and perhaps safeguard the health and wellbeing of the numerous people consuming yoghurt products.MethodsA total of 40 yoghurt samples consisted of 20 traditionally (unbranded) and 20 commercially produced (branded) were analysis for physicochemical property (pH, moisture, ash, fat, Total Solid (TS) and Solid Not Fat (SNF)) and microbial quality (Coliform Count (CC) and Yeast and Mould Count (YMC) were performed using TEMPO system whereas; Total Viable Count (TVC) was performed according to standard culture method).ResultsIn the traditionally produced (unbranded) yogurt samples, the fat content was 4.44%, pH 3.99, TS content 10.12%, SNF content 7.18%, moisture content 89.88%, and ash content 0.53%. For the commercially produced (branded) yogurt samples, the fat content was 5.02%, pH 3.88, TS content 10.66%, SNF content 8.10%, moisture content 89.29%, and ash content 0.62%. The TVC in traditionally (unbranded) and commercially produced (branded) yoghurt samples was found to be 10.72 and 10.35 log10 cfu/mL, respectively. In terms of coliform counts (CC), 20%, 55%, and 25% of the traditionally produced yogurt samples had counts of < 10 cfu/mL, 10 to < 4.9 × 104 cfu/mL, and > 4.9 × 104 cfu/mL, respectively. For the commercially produced yogurt samples, 40%, 35%, and 25% fell within these same ranges. The overall mean coliform counts were 3.72 log₁₀ cfu/mL for traditionally produced yogurt samples and 2.81 log₁₀ cfu/mL for commercially produced yogurt samples; however, the difference was not statistically significant (P > 0.05). Similarly, for yeast and mold counts (YMC), 0%, 35%, and 65% of traditionally produced yogurt samples had counts of < 100 cfu/mL, 100—< 4.9 × 104 cfu/mL, and > 4.9 × 104 cfu/mL, respectively. In commercially produced yogurt, 30%, 50%, and 20% of samples fell within these same ranges. The overall mean YMC was 4.48 log₁₀ cfu/mL for traditionally produced yogurt samples and 3.92 log₁₀ cfu/mL for commercially produced yogurt samples, but this difference was also not statistically significant (P > 0.05).ConclusionBased on the findings of this study, it is crucial to implement measures to improve the quality of yogurt in Addis Ababa to ensure consumer safety and product consistency.

Effect of lotus (Nelumbo Nucifera, G.) rhizome powder as a fat replacer on the quality attributes of muffins

Lotus (Nelumbo nucifera, G.) is a perennial aquatic plant, which is utilized for a variety of therapeutic and food applications. Muffins are a kind of baking product that is typically consumed for breakfast or as a snack. Currently, many baked goods in the market use fat replacers to lower the overall fat content, while conserving consumer approval. The study's objectives were to produce low-fat muffins and to characterize the types of quality changes that occurred in the muffins. Lotus rhizome was sliced, dried and converted into powder, which used as fat substitute in muffins, at 0, 5, 10, 15 and 20% replacement levels, with names as M0, M1, M2, M3 and M4, respectively. Composite flours having these proportions of lotus Rhizome Powder (LRP) were analyzed for proximate and rheological parameters. Increasing levels of LRP caused increased water absorption and dough development time of the composite flours. Proximate analyses of muffins showed highest value of moisture (25.05%), ash (2.43%), fiber (0.99%), protein (11.89%) and NFE (58.45%) in M4. Whereas, fat content and energy value were significantly reduced in M4, as highest fat was found to be in M0 (36.65%) and highest calories in M0 (576.5 kcal), which were significantly reduced to 26.24% and 514.5 kcal, respectively in M4. High yeast and mold count was of M0 at first day as 98 CFU/g, which was increased to 129 CFU/g at day 7, whereas M4 presented this count to be 44 CFU/g at day one, which was increased to 70.33 CFU/g at day 7. Texture analysis showed softest texture of M4 as firmness value was 1887 g, which was significantly high in M0 as 2285 g. The research revealed that M3 best performed out of all treatments as 15% replacement of fat with LRP significantly improved the rheological properties of the flour, ash and fiber content were high, whereas fat contents were significantly low in these muffins. Textural and sensory analysis also supported the M3 due to softer texture and significantly high color, appearance, flavor, and overall acceptability scores. From the results of this study, it could be concluded that a 15% replacement of shortenings with LRP could be considered as optimum for developing good quality baked muffins.Graphical

Extension of Shelf Life of Roasted Duck by combination of Vacuum Packaging and Low Temperature Storage

A study was conducted to assess the shelf life of roasted duck under aerobic and vacuum packaging and in refrigerator (4±1° C) and freezer (-18±1° C) storage. The samples were analyzed for moisture content, pH, Thiobarbituric Acid (TBA) Value, Tyrosine value, Total Plate Count (TPC), Total Psychrophilic Count (TPSC), Yeast and Mould Count (YMC), colour, flavour and tenderness. The products showed an increasing trend in pH, TBA value, tyrosine value, TPC, TPSC and YMC during the storage period in refrigerated and freezer temperatures irrespective of the packaging methods i.e. aerobic and vacuum, whereas, the moisture content, colour, flavor and tenderness of the product followed a declining trend during storage. Though the sensory parameter scores declined during storage, but these changes were less in the vacuum packed and frozen products. The study showed that the aerobically packed roasted duck was acceptable upto 7th day and vacuum packed roasted duck was acceptable upto 14th day in the refrigerated storage. The freezer storage extended the shelf life of the roasted duck till 40th day in aerobic packaging while the combination of freezer storage and vacuum packaging extended the shelf life of the roasted duck till 60th day. These findings have significant implications for the food industry, enabling the development of strategies to extend the shelf life of roasted duck and reduce food waste.

Potential Production of Mycotoxins by the Fungal Flora Isolated from "Garba" (Côte D'ivoire)

Garba, an Ivorian dish composed of attiéké (a fermented cassava couscous), fried tuna, and condiments, is increasingly consumed by the population, particularly in the streets of Abidjan. However, garba could pose a health risk to consumers. This study, aimed at preserving public health, sought to identify the toxigenic fungal flora present in garba sold on the streets of Abidjan. To this end, 300 garba samples were collected from four districts of Abidjan. Fungal strains contaminating the garba were enumerated and identified using classical mycological methods. Mycotoxins (aflatoxins and ochratoxins) were quantified using High-Performance Liquid Chromatography (HPLC). Results showed that the average mold counts ranged from 0 to 1.8 x 10^3 CFU/g. The isolated mold strains belonged to ten species grouped into four genera: Aspergillus, Mucor, Penicillium and Paecilomyces, with Mucor spp. (36.89%) and Aspergillus niger (30.09%) being the most predominant. The mycotoxins detected in garba were aflatoxins (B1, B2, G1, and G2) and ochratoxin A, with average levels ranging from 0.42 to 8.07 µg/kg. Approximately 37% and 23% of garba samples had total aflatoxin and aflatoxin B1 levels exceeding regulatory limits. The presence of potentially mycotoxigenic fungal strains in garba could pose a health risk to consumers. Compliance with good hygiene practices during the production and sale of garba will therefore be necessary to considerably reduce contamination and protect consumer health.

Effect of gamma radiation on sensory, microbial and lipid quality of whole Indian mackerel (Rastrelliger kanagurta)

The study focused on the impact of γ-radiation on the lipids, sensory attributes, and microbial quality of fresh whole mackerel. Fish were irradiated at 2, 4 and 6 kGy doses; subsequently, microbial load, sensory quality and fatty acid composition were studied. The results indicated no significant changes in sensory quality up to 6 kGy dose. The bacterial load of 4.75 log CFU/g was reduced to 3.54, 2.74, 2.17 log CFU/g at 2, 4 and 6 kGy doses respectively. The total mould count reduced from 1.17 log CFU/g to 0.7 log CFU/g at 2 kGy, and was below the detection limit at 4 and 6 kGy. No significant difference was observed in fatty acid composition at a dose of 2 kGy compared to control samples. However, a significant increase in saturated fatty acid and monounsaturated fatty acid with a significant decrease in polyunsaturated fatty acid content was detected at 4 and 6 kGy doses. Based on these findings, the study suggests that gamma irradiation at 4 kGy is effective for microbial safety with minimal impact on fatty acid composition.

Hygienic Production Practices and Microbiological Quality of Sheep Milk in Ararso District of Jarar Zone, Somali Regional State, Ethiopia

This study was conducted to evaluate the hygienic production practices and microbiological quality of sheep milk in Ararso district of Jarar Zone, Somali Regional State, Ethiopia. A stratified sampling strategy was used to choose 180 households specifically for this investigation. A total of 60 pooled raw sheep milk samples (each containing 200 mL) were collected from the udders and milk handling equipment of selected milk producers in the research area. The samples were examined to determine microbiological quality. The data were gathered via a questionnaire, field observation, key informant interviews, and focus group discussions. The vast majority of respondents in pastoral (86.7%) and agro-pastoral (64.4%) production systems were illiterate. The majority of respondents (70.6%) in the research area cleaned the sheep home (kraal) once every two days. The majority (98.3%) of respondents in the research area milk their sheep in open kraals with no roof or walls. As a consequence, 36.7% of pastoral and agro-pastoral respondents (81.1%) reported cleaning milk vessels on a regular basis. Almost all of the responders in the research area used plastic equipment for milking and handling. The majority of responders in pastoral and agro-pastoralist categories placed barn hygiene first, with indexes of 0.24 and 0.23, respectively. The average total bacterial count (TBC), coiform count (CC) and yeast and mould count (YMC) of raw sheep milk samples were 5.13±0.21, 2.89±0.27, and 0.77±0.21 log10 cfu/mL, respectively. Raw sheep milk samples taken from producers’ milk handling equipment had a substantially higher mean total bacterial count (5.78±0.32 log10 cfu/mL) compared to samples collected from the udder (4.48±0.23 log10 cfu/mL). Milk samples from pastoral and agro-pastoral households had an average coliform count of 3.18 and 2.60 log10 cfu/mL, respectively. The average YMC in milk samples from pastoralists and agro-pastoralists were 0.74 and 0.80 log10 cfu/mL, respectively. In general, pastoralists and agro-pastoralists in the district do not practice hygienic milking and handling. Consequently, the implementation of hygienic milk production and handling practices is essential to enhance the safety and quality of sheep milk in the study area. Additionally, further research should be undertaken to investigate the microbiological aspects and assess the safety and quality parameters of sheep milk in greater detail.

Influence of storage time of fermented soghurt on the changes in fat and protein biomolecules through Confocal Laser Scanning Microscopy (CLSM) under refrigeration condition

The aim of the study is to assess the significance of storage duration on fermented Soghurt (soy curd), focusing on changes in fat and protein biomolecules analyzing with CLSM, viscosity measurements, and particle size distributions under refrigerated conditions. Soghurt prepared with 1% yogurt culture (Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus) was analyzed for storage stability under refrigerated conditions for up to 15 days measuring the pH, acidity, microbial counts, viscosity, particle size distribution and scanning electron microscopy for structural analysis. Even though lactic counts were not affected significantly during the storage periods, yeast & mold counts and coliform counts were absent up to 15 days during the storage. However, the product could be stored upto 7 days under refrigeration condition (6–8 °C). During the storage period, it was observed that the viscosity of soghurt increased with increase in storage time. Particle size distribution was estimated during the entire storage periods for soghurt and it was observed that smaller particle was mostly found in the range of 3.0–50.0 µm while bigger particles were in the range of 57.0–910.0 µm. Further, larger aggregates with big particle sizes were observed during prolonged storage period. The CLSM study showed the appearance of proteins and fats being dispersed slowly during the storage due to the proteolytic and lipolytic activities of yoghurt cultures after 5 days of storage under refrigeration condition.

Optimization of aloe vera‐sodium alginate composite coating using L16 orthogonal design for extension of shelf life of mushroom

AbstractWhite button mushrooms are highly nutritive, rich in various macro and micro nutrients, however, have a short shelf life with weight loss (WL), enzymatic browning, and loss in firmness as the major quality defects. The present study was carried out to investigate the effect of aloe vera‐sodium alginate (AV‐SA) composite coating on the quality attributes of mushroom. The development of coating formulations containing 2% sodium alginate along with varying concentration of aloe vera gel 20%–80% and storage time 4–16 days was planned using a 2‐factor 4‐level orthogonal array (L16) design of Taguchi technique. The influence of both the process parameters on the WL, total soluble solids (TSS), respiration rate (RR), browning index (BI), firmness, electrolyte leakage rate (EL), malondialdehyde (MDA), ascorbic acid (AA), total phenolic content (TPC), enzymes activity (polyphenol oxidase and peroxidase), and yeast and mold count (YMC) were evaluated and the optimized level of parameters was determined on the basis of the highest S/N ratios of the responses. The results indicated that 60% AV‐SA composite coating could extend the shelf life of white button mushrooms for up to 8 days with retarded loss in weight, firmness, AA, and TPC and reduced increase in TSS, BI, EL, MDA with controlled enzymatic activity, RR, and YMC.

Quality changes of durian pulp (Durio ziberhinus Murr.) in cold storage

Abstract In this study, the effects of four types of polystyrene (PS) plastic box with polyethylene terephthalate (PET) lid (PSPET), PS tray with polyethylene (PE) bag (PSPE), PS tray with a vacuumed PE bag (PSVPE), and PET box with a sealed lid (PET) on the quality of durian fruit during storage at 10°C were investigated. The analysis results showed that in all four types of packaging, the total aerobic bacteria count in the durian pulp ranged from 101 to 105 CFU/mL after storage. However, total yeast and mold count was not detected. During the same survey period, PET packaging for the product had the lowest weight loss of 0.58–3.07%. Next, the impact of temperature, at 0 and 10°C, on the quality stability of durian fruit during storage was also studied and evaluated. Durian pulp preserved in PET at two different cold temperatures did not show any significant difference in microbial content and phytochemical composition. Total aerobic bacteria count in the samples was recorded at about 104 CFU/g after storage; total yeast and mold count was not detected, and the weight loss reached 1.82 and 1.72% at temperatures of 0 and 10°C, respectively.

Development of plant-based yogurt from munguba (Pachira aquatica) seeds: Stability and predictive growth of lactic acid cultures

Lactic fermentation is employed to enhance the nutritional quality of plant-based milks, and exploring underutilized plant matrices like munguba (Pachira aquatica) can bring innovation to the plant-based beverage market. This study aimed to develop a yogurt from munguba seeds and investigate the fermentation kinetics of lactic acid bacteria (LAB), as well as the product's stability during storage. Munguba seed milk was prepared through cleaning, peeling, blanching, blending, filtering, and storing at 5 °C. Fermentation was conducted with Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, and Lactobacillus fermentum at 36 °C, and microbial growth was monitored to construct a LAB growth curve. Ultra High Temperature (UHT) whole cow's milk was used for comparison. Munguba seed milk fermented for 9 h showed LAB growth from 3.89 to 8.22 log CFU/mL, while UHT cow's milk fermented for 6 h showed LAB growth from 4.55 to 6.33 log CFU/mL. The Baranyi model showed good fits for both data sets (R2 of 0.9528 for munguba milk and 0.9340 for UHT milk). Specific growth rates, doubling times, and multiplication rates were higher for munguba milk (μ of 1.10 h^-1, td of 0.66 h, MR of 1.59 h^-1) compared to UHT milk (μ of 0.85 h^-1, td of 0.84 h, MR of 1.22 h^-1). LAB, mold, and yeast counts, pH, and lactic acid content remained stable over 31 days of refrigerated storage of munguba seed yogurt. These results indicate that munguba seed milk is a promising substrate for fermented beverages and beneficial microorganisms.

Indigenous Lactic Acid Bacteria as Antioxidant Agents in the Production of Organic Raw Fermented Sausages.

The study aimed to assess the impact of lactic acid bacteria (LAB) strains on the antioxidant, physico-chemical properties, and microbiological quality of fermented sausages. Five treatments of raw sausages were prepared: two controls without LAB addition (C, P), and three samples with LAB addition (SCH1, BAL6, KL14). Fatty acid composition, cholesterol content, physico-chemical, microbiological tests, and antioxidant assays, were performed at time 0 and after 1 and 2 months of storage. A significantly higher ability to scavenge free radicals of DPPH (2,2-diphenyl-1-picrylhydrazyl) was found in sausages with all LAB strains. In the case of the ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) test, it was noted that KL14 treatment had higher antioxidant activity. The main fatty acids in sausages were monounsaturated and saturated. A significantly lower cholesterol content was observed in sausages with the addition of LAB. Sausages with LAB strains differed significantly in pH value. Water activity decreased significantly during storage. After 2 months of storage, the sausages with BAL6 and KL14 strains were characterized by significantly lower redox potential and a lower TBARS (thiobarbituric acid reactive substances) index. It was found that P sausages had the darkest color. SCH1, BAL6, and KL14 strains were also capable of producing red color. The total number of microorganisms in the sausages was high, which is mainly due to the high LAB content and yeast and mold counts. No spoilage or pathogenic microflora were detected. Indigenous LAB strains have the potential to improve the quality and safety of fermented meat products.