Journal of Food Quality最新文献

Postharvest vegetables are still undergoing metabolic processes primarily through respiration. Although modified atmosphere packaging (MAP) can extend the shelf life of vegetables, it is of great significance to accurately predict the shelf life of vegetables for the quality assurance. In this study, the modified atmosphere packaged spinach and Chinese chives were stored at 0, 5, 10, 15, and 20°C, and Pseudomonas spp. count was determined regularly. The modified Gompertz model was used as the primary model to construct the model of Pseudomonas spp. growth kinetics in spinach and Chinese chives at different temperatures. On the basis of the primary model, the Belehradek (square root) model was selected as the secondary model to explore the influence of temperature on maximum specific growth rate (μ_max) and lag period (λ). Finally, the shelf life prediction model of spinach and Chinese chives was established and verified. From the results, the growth of Pseudomonas spp. showed an S-shaped curve at different storage temperatures. With the increase of storage temperature, μ_max of microorganisms increased and λ decreased. The modified Gompertz model can describe the growth dynamics of Pseudomonas spp. well, and μ_max^0.5 and (λ^-1)^0.5 have a good linear relationship with storage temperature. The accuracy of the shelf life prediction model was verified by measuring the growth state of Pseudomonas spp. in modified atmosphere packaged spinach and Chinese chives at the storage temperature of 8°C. The results showed that the relative error between the predicted value and the measured value was 2.39% for spinach and 0.43% for Chinese chives, respectively, indicating that the shelf life prediction model could effectively predict the shelf life of spinach and Chinese chives at the storage temperature range of 0°C–20°C.

Adiantum capillus-veneris L. is known for its bioactive compounds and health benefits. In this study, the physicochemical, functional, and sensory properties of set-type yogurt fortified with Adiantum capillus-veneris L. extract (ACVE) were evaluated during 21 days of storage. Higher pH values and lower acidity were observed in yogurts containing 0.25% and 0.5% ACVE on Day 21 of storage. ACVE enhanced water holding capacity (WHC), a^∗ and b^∗ values, total phenolic content (TPC), antioxidant activity, and α-amylase inhibition (by more than three times). Additionally, the yogurts containing 0.25% and 0.5% ACVE showed a higher storage modulus, complex viscosity, and a more compact microstructure. Moreover, ACVE reduced syneresis and the L^∗ value of yogurt (p < 0.05). The addition of 0.25% and 0.5% ACVE in yogurt significantly reduced the LAB on the first day of storage. However, ACVE-fortified yogurts exhibited significantly higher LAB counts at the end of the storage (p < 0.05). An increase in acidity and a decrease in pH were observed with prolonged storage, except in yogurt with 0.5% ACVE. The TPC, antioxidant activity, WHC, and LAB counts of fortified yogurts were enhanced during storage, whereas syneresis and α-amylase inhibition were reduced (p < 0.05). Sensory evaluation indicated that all yogurts were acceptable, and no significant difference in overall acceptance was observed between yogurts containing 0.1% and 0.25% ACVE and the control (p > 0.05). Therefore, ACVE (particularly at levels up to 0.25%) can be used as a novel functional additive to enhance the quality characteristics of yogurt.

In this study, pomegranate peel powder (PPP) was added to the formulation of snack meat sticks at different ratios (control, 2.5%, 5%, and 10%), and physicochemical, microbiological, sensory, and economic properties of the products were evaluated. Increasing PPP levels significantly enhanced the total phenolic content and antioxidant activity, while reducing pH, water activity, and thiobarbituric acid-reactive substances (TBARS), indicating improved oxidative stability. It was found that the addition of PPP also affected the cross-sectional surface color of the snack sticks (p < 0.05). Moreover, a notable decline was observed in the springiness and chewiness of snack sticks with the increasing ratio of PPP. Finally, snack sticks containing 2.5% PPP had higher sensorial scores. Microbiological assessments confirmed the safety of all formulations. As a result, the use of PPP could improve the quality of snack sticks, making them more economical and functional.

Military personnel operating in field environments often experience energy deficits due to limited access to adequate nutrition. Therefore, the development of high-calorie, shelf-stable, and nutrient-dense foods is essential to sustain their performance and health. This study aimed to formulate and evaluate the nutritional and microbiological quality of such high-calorie foods using locally available raw materials, guided by a design of experiments approach. Ten distinct food formulations were developed based on a mixture design plan. Physicochemical and microbiological parameters were analyzed according to ISO and AOAC standards. The results revealed protein contents ranging from 20.86 to 29.84 g/100 g, carbohydrates from 33.39 to 48.39 g/100 g, and fat from 18.71 to 33.71 g/100 g, with a maximum energy value of 520.40 kcal/100 g. A radar chart illustrated that F7 was the richest in protein, F9 had the highest lipid content, and F8 contained the most carbohydrates. The pH, humidity, dry matter, total ash, and °Brix values ranged from 4.30 to 5.03, 12.04% to 27.04%, 72.96% to 87.96%, 3.84% to 20.60%, and 0.67 to 1.40, respectively. The contents of sodium, calcium, magnesium, zinc, potassium, and iron (mg/100 g) varied between 55.68 and 1172.8, 59.75 and 126.3, 44.59 and 92.26, 1.14 and 2.18, 596.64 and 838.68, and 2.21 and 4.95, respectively. Microbiological analyses confirmed the absence of pathogenic microorganisms, including Salmonella spp., Escherichia coli, and Staphylococcus spp. The novelty of this study lies in the integration of physicochemical, nutritional, and microbiological profiling within a formulation optimization framework which demonstrates an innovative approach to the development of stable, nutrient-rich, and high-calorie foods from locally sourced ingredients. These findings demonstrate also the potential for locally sourced ingredients to support the development of fortified foods for both military and sports applications.

Radix Paeoniae Alba (RPA), as a kind of health food and herbal medicine with a remarkable curative effect, has an increasing market demand in recent years. Due to its numerous processing methods, the influence on internal active components is complex, and the curative effect varies greatly. However, in some cases, different processed products are confused, and it is of great significance to strictly control the quality of RPA and its processed products. In this study, electronic eye (e-eye) and electronic nose (e-nose) were used to rapidly evaluate the quality of RPA and its processed products and were compared with high-performance liquid chromatography (HPLC). The results showed that the surface brightness of RPA was higher than that of processed products, and the red and yellow tones of stir-fried RPA were the deepest. L^∗, b^∗, E^∗, c^∗, and color index (CI) contributed greatly to distinguish RPA from its processed products. The processing methods had obvious effects on the flavor characteristics of RPA, and heptadecan-2-one, 2-methyl propanoic acid, alpha-pinene, pent-1-en-3-ol, but-(E)-2-enal, and propanoic acid were selected to be critical components for distinguishing RPA from its processed products. Correlation analysis revealed that the ingredients in RPA exhibited significant associations with color and odor. Compared with HPLC, e-eye and e-nose could distinguish RPA from different processed products more quickly and accurately, which provided a meaningful reference for the quality control of other foods and herbal medicines with various processing methods.

The study was conducted to evaluate the hygienic practices, handling methods, microbial quality, and safety of raw camel milk at various supply points during the dry and wet seasons in the Borana zone. A total of 370 respondents were interviewed for hygienic camel milk handling along the supply chains (farms, collection points, and open markets), and 192 camel milk samples were collected from surveyed respondents of camel herders, primary collectors, and retailers. Milk sampling, sample collection, handling, transportation, and analysis followed standard procedures. Unhygienic practices, poor handling procedures of camel milk, and lack of standard milk containers were observed across supply chains, which contributed to microbial contaminations. Significant (p < 0.05) increases in counts of total bacteria, total coliform, yeast and mold, Enterobacteriaceae, and Staphylococcus aureus of raw camel milk samples from farms during the wet season to markets during the dry season with mean log₁₀ CFU/mL of 5.21–8.35, 4.99–7.24, 3.86–7.29, 4.30–7.12, and 3.31–5.32 were observed, respectively. The overall average count of total bacteria, total coliform, yeast and mold, Enterobacteriaceae, and Staphylococcus aureus was 7.04, 6.09, 5.45, 5.75, and 4.30 log₁₀ CFU/mL, respectively. These findings indicate that raw camel milk in the Borana zone is highly contaminated, with microbial loads exceeding established raw milk standards. Such high microbial contaminations justify the need for proper heat treatment of raw camel milk before consumption. In addition, community training and awareness creation on improving hygienic milk handling practices and the introduction of dairy material across milk supply chains are crucial to enhancing the quality of camel milk.

Color, as an essential visual quality characteristic of fish that determines consumer preferences and purchasing decisions, serves as a quick indicator of freshness. However, determining whether fish has undergone previous freezing poses a challenge. Traditional methods such as sensory evaluation, physicochemical, biochemical, and microbiological analyses, despite being time-consuming and costly, have been employed for this purpose among various fish species. This study aims to differentiate frozen-thawed (at −20°C and −60°C) and fresh fish samples through deep learning-based image analysis. A dataset comprising frozen-thawed and fresh Vermilion snapper (Rhomboplites aurorubens) images was used to extract features with four pretrained CNN models (VGG16, ResNet50, InceptionV3, and EfficientNetB0), followed by a neural network for classification. For comparison, the same classifier was applied to traditional L^∗, a^∗, and b^∗ color values (commonly used in conventional analyses) extracted from the images. The CNN-based models consistently outperformed the traditional approach. In the binary classification task (fresh vs. frozen), VGG16 achieved the highest accuracy of 96.8%, compared to 80.0% using color features. In the more challenging three-class classification (fresh vs. −20°C vs. −60°C), EfficientNetB0 achieved an 86.9% accuracy, outperforming the 64.0% accuracy of the color-based approach. Additionally, for left- vs. right-side classification, ResNet50 reached a 96.0% accuracy, while color-based classification achieved only 52.0%. These findings suggest that CNN-based image analysis can be a valuable tool for the seafood industry, providing a nondestructive, faster, more reliable alternative to conventional methods for assessing the freshness and freezing history of fish products.

Medium-chain dicarboxylic acids (MCDAs), including glutaric acid (GLA), succinic acid (SUA), and azelaic acid (AZA), have been extensively studied for pharmaceutical applications but remain underutilized in the meat industry. This study evaluated the antibacterial properties and antioxidant potential of AZA, SUA, and GLA. Their ability to enhance the quality and safety of sliced and minced beef was also assessed. The results revealed that the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for these MCDAs generally ranged between 500 and 2000 μg/mL, with AZA exhibiting lower MIC and MBC values than SUA and GLA. However, the antioxidant activity of these MCDAs was found to be limited. Application of these MCDAs to refrigerated raw beef demonstrated their efficacy in maintaining freshness and extending shelf life. These MCDAs were particularly beneficial in preserving color, pH, and moisture levels while reducing spoilage markers such as total volatile base nitrogen and bacterial counts. Overall, the findings suggest that these MCDAs exert dose-dependent effects in refrigerated sliced and minced beef models, with AZA delivering the most pronounced benefits.

Consumption of contaminated meat and meat by-products has been associated with several foodborne outbreaks worldwide. Particularly in informal markets, poor hygiene during slaughter, transportation, and sale, as well as inadequate sanitation at points of sale and noncompliance with good hygiene practices, are major contributors. In this context, the five more representative markets in Luanda were selected (Catinton, Kifica, Benfica, Km30, and Kikolo). Three types of meat samples (beef, pork, and goat) were randomly collected in each market, totaling 130 meat samples. Meat was analyzed according to ISO guidelines for enumeration of Enterobacteriaceae, Enterococcus, and Escherichia coli (hygiene indicator) and detection of Salmonella (food safety indicator). In the selected markets, the sellers were characterized using observational methods and through sociographic questionnaires based on short interviews. These approaches showed that 61.2% of the sellers were young (20–30 years old), with 58.6% not having completed elementary education. More than 75% of the sellers had been working in this sector for less than 5 years, and most did not adhere to appropriate food safety practices when handling fresh meat. Unsatisfactory microbiological quality was found in all types of meat and markets. In the Benfica market, the detection of Salmonella raised significant concerns, with 100% of beef, 90% of pork, and 60% of goat meat samples testing positive. In the other four markets (Catinton, Kifica, Km30, and Kikolo), the level of contamination with E. coli was the main factor, leading to unsatisfactory results. Significant differences in microbiological indicators were observed between markets. Overall, the Kikolo market exhibited the highest levels of contamination. To our knowledge, studies on the microbiological quality and safety of fresh meat sold in informal markets in Angola are few or nonexistent. Therefore, the findings of the present study provide critical insights that could contribute to mitigating the risk of contamination of fresh meat with pathogenic microorganisms, with the concomitant possibility of foodborne outbreaks in Luanda. There is an urgent need to invest in adequate infrastructure for the sale of fresh meat, such as covered buildings with piped drinking water, sewage, and refrigeration systems, as well as training sellers in good handling practices (GHPs) and good manufacturing practices (GMPs).