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Abstract This study investigates the impact of environmental factors on the quality changes of mackerel (Scomber japonicus), a globally significant fish species valued for its high nutritional content, especially its unsaturated fatty acids and proteins. In South Korea, marine products like mackerel undergo auction, sorting, packaging, and transportation. Assessing the fish freshness and quality during these processes, before it reaches consumers, is crucial. This research aimed to track the changes in mackerel quality indicators after the auction and correlate them with the environmental factors affecting transportation. Using a transportation model established for both summer and winter, mackerel samples were categorized by their weight (200 and 300 g). Results show poorer quality indicators in summer compared to winter, particularly in the 200 g group. Microbiological indicators such as the total viable count (0.923) and total coliforms (0.958) were most strongly correlated with the season, whereas the lipid oxidation indicators acid value (0.627) and peroxide value (0.536) were moderately correlated with the season. Interestingly, the wider standard deviation distribution observed in summer suggests that individual mackerel characteristics may influence the degree of quality changes. These findings offer insights into mackerel quality fluctuations during auction and transportation, aiding in future efforts to maintain seafood quality amidst climate change.

This study was undertaken in order to explore the correlation between the quality changes and microbial community in sauced duck necks during cold storage. Commercial sauced duck necks in modified atmosphere packaging were stored at 4 ℃ for 1, 4, 7, 10, and 13 days, and the changes in pH, thiobarbituric acid reactive substances (TBARS) value, color, texture, total bacterial count, total volatile base nitrogen (TVB-N) content, and microbial community were analyzed. The results showed that the pH initially decreased and then increased with storage time, while brightness (L*), redness (a*), yellowness (b*) and hardness exhibited a decreasing trend, and elasticity, chewiness, cohesiveness and adhesiveness showed an initial increase followed by a decrease. The total bacterial count, TVB-N and TBARS values all gradually increased during storage, with the total bacterial count and TVB-N exceeding the acceptable limits on the 10th day. Microbial diversity diminished gradually with storage time. At the initial stage of storage, the dominant bacteria were Rhodococcus, Acinetobacter, Ureibacillus and Symbiobacterium, while those in the late storage period were Rhodococcus, Acinetobacter, Leuconostoc and Lactobacillus. Principal co-ordinate analysis indicated the two principal coordinates explained 74.03% of the variation, and differences in microbial community composition occurred after 4 days of storage. Correlation analysis showed that Leuconostoc was positively correlated with pH, total bacterial count, TVB-N content and TBARS value during cold storage of sauced duck necks, indicating that Leuconostoc was the primary spoilage bacteria during storage.

This study was undertaken in order to explore the correlation between the quality changes and microbial community in sauced duck necks during cold storage. Commercial sauced duck necks in modified atmosphere packaging were stored at 4 °C for 1, 4, 7, 10, and 13 days, and the changes in pH, thiobarbituric acid reactive substances (TBARS) value, color, texture, total bacterial count, total volatile base nitrogen (TVB-N) content, and microbial community were analyzed. The results showed that the pH initially decreased and then increased with storage time, while brightness (L*), redness (a*), yellowness (b*) and hardness exhibited a decreasing trend, and elasticity, chewiness, cohesiveness and adhesiveness showed an initial increase followed by a decrease. The total bacterial count, TVB-N and TBARS values all gradually increased during storage, with the total bacterial count and TVB-N exceeding the acceptable limits on the 10th day. Microbial diversity diminished gradually with storage time. At the initial stage of storage, the dominant bacteria were Rhodococcus, Acinetobacter, Ureibacillus and Symbiobacterium, while those in the late storage period were Rhodococcus, Acinetobacter, Leuconostoc and Lactobacillus. Principal co-ordinate analysis indicated the two principal coordinates explained 74.03% of the variation, and differences in microbial community composition occurred after 4 days of storage. Correlation analysis showed that Leuconostoc was positively correlated with pH, total bacterial count, TVB-N content and TBARS value during cold storage of sauced duck necks, indicating that Leuconostoc was the primary spoilage bacteria during storage. [ABSTRACT FROM AUTHOR]

旨在为实现鲜食核桃周年供应提供技术支持，以‘强特勒’核桃为研究对象，探究脱青皮鲜核桃在冻藏过程（-10 ℃，10个月）中感官品质、色差、营养成分、油脂理化指标（过氧化值和酸值）等品质的变化。结果表明：‘强特勒’脱青皮鲜核桃在-10 ℃条件下冻藏10个月后，其种皮颜色、种皮分离度、种仁颜色、香气、风味的品质级别均下降，即感官品质下降；种皮和种仁的色差随着冻藏时间的延长不断增大，且种皮色差的变化程度较种仁的大；蛋白质、脂肪和可溶性糖含量下降；脂肪酸组成无变化，但不饱和脂肪酸相对含量上升，饱和脂肪酸相对含量下降；氨基酸组成和矿物元素种类均无变化；油脂过氧化值和酸值均呈上升趋势，但均符合LY/T 3004.8—2018《核桃 第8部分:核桃坚果质量及检测》的限量规定。综上，‘强特勒’脱青皮鲜核桃在冻藏过程中品质变化不大，可实现周年供应。Aiming to provide technical support for the realization of annual supply of fresh walnut, Chandler walnut was used as the research object to investigate the changes of sensory quality, colour difference, nutrient content of the walnut, and physicochemical indexes (peroxide value and acid value) of the oil during the freezing storage of peeled fresh walnut at -10 ℃ for 10 months. The results showed that the quality levels of seed coat colour, seed coat separation, seed kernel colour, aroma and flavour of peeled fresh Chandler walnut declined after 10 months of storage at -10 ℃, indicating the sensory quality decreased. The colour difference between seed coat and seed kernel increased with the prolongation of freezing storage time, and the degree of colour difference of seed coat was greater than that of seed kernel; the relative contents of protein, fat and soluble sugar decreased; the composition of fatty acid did not change, the content of unsaturated fatty acid increased, while the relative content of saturated fatty acid decreased. There was no change in the types of amino acids and mineral elements; both the peroxide value and acid value of the oil increased, but met with the limit of LY/T 3004.8-2018 Walnuts—part 8: Quality and inspection of walnut nuts. To sum up, the quality of peeled fresh Chandler walnut has few changes during freezing storage, so it can be supplied all year round.

Objective: A coupled model for predicting tomato quality during short-term storage and transportation under extreme temperatures, utilizing the Arrhenius equation in conjunction with meteorological temperature data, to forecast the quality changes in tomatoes during the short-term storage and transportation processes under extreme weather conditions. Methods: Analyzing the meteorological temperature data for the year 2020 in Weifang, Baoding, and Daxing, 7 temperature points were selected to simulate the range of temperature variations for short-term storage and transportation of tomatoes. By utilizing the Arrhenius equation and integrating temperature with weight loss rate, hardness, color difference (ΔE), and sensory evaluation scores (SE), a coupled model was developed for predicting tomato quality. The model was validated by using temperatures of -10 ℃ and 12 ℃. Results: Within 48 hours of storage and transportation, Loss rate and ΔE of tomatoes gradually increased, while evaluation scores (SE) and hardness decreased gradually. The quality prediction coupling model based on the Arrhenius equation combined with meteorological temperature data was constructed. Under storage conditions from 0 to 36 ℃, changes in loss rate and SE were fitted with zero-order reactions, while changes in hardness and ΔE were fitted with first-order and half-order reactions, respectively. For storage conditions from -15 to 0 ℃, zero-order reaction fits were applied to model the changes in SE, ΔE, weight loss rate, and hardness. Validation of the predictive model revealed that, under 12 ℃ storage conditions, the relative errors for tomato weight loss rate, hardness, and SE were within 15%, except for the 48 hour prediction. Under -10 ℃ storage conditions, the relative errors for tomato hardness and SE were within 15%, excluding the 48 hour prediction. Conclusion: The coupled model for tomato quality prediction, constructed by integrating the Arrhenius equation with extreme meteorological temperature data, proves to be effective in forecasting the quality of tomatoes under extreme temperature conditions.

【Objective】The study aims to explore the change law of fruit quality of the main citrus varieties in Ruili area of Yunnan Province during maturity, offering a theoretical foundation for identifying the appropriate time for fruit harvesting.【Method】Four citrus varieties including Orah, Bingtang, Murcott, and W·Murcott were used as tested materials. Fruits were harvested 150-330 d after flowering (August 12, 2020 to February 8, 2021) and 240-405 d after flowering (November 8, 2021 to April 28, 2022). Samples were taken every fifteen days routinely, and the quality of the fruits was determined.【Result】The single fruit quality and the fruit horizontal and longitudinal diameters of the four citrus varieties exhibited a trend of growing first and then flattening as the maturity of fruits. Orah, Bingtang, Murcott and W·Murcott fruits terminated their rapid growth and expansion period before 270, 255, 300 and 285 days after flowering, respectively. In a span of two years, except for Murcott (with transition period being consistent in the first and the second year), the color transition period of W·Murcott peel was earlier in the first year, and the color transition period of Orah and Bingtang was later than the first year. Bingtang, Orah, Murcott and W·Murcott all showed stable mass fractions of total soluble solids content (TSS) after 240, 315, 300 and 270 days of flowering, respectively; while the mass fractions of titratable acid content (TA) showed no significant change at 180, 210, 240 and 240 d of flowering, respectively.【Conclusion】Combining the indicators such as single fruit weight, horizontal and longitudinal diameter, peel colour, and mass fraction of internal substance content, the fruits of Orah, Bingtang, Murcott, and W·Murcott reach harvest maturity at 315, 255, 300, and 285 d after flowering, which are suitable for harvesting.

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Highly prized for its unique taste and appearance, pitaya is a tasty, low-calorie fruit. It has a high-water content, a high metabolism, and a high susceptibility to pathogens, resulting in an irreversible process of tissue degeneration or quality degradation and eventual loss of commercial value, leading to economic loss. High quality fruits are a key guarantee for the healthy development of economic advantages. However, the understanding of postharvest conservation technology and the regulation of maturation, and senescence of pitaya are lacking. To better understand the means of postharvest storage of pitaya, extend the shelf life of pitaya fruit and prospect the postharvest storage technology, this paper analyzes and compares the postharvest quality changes of pitaya fruit, preservation technology, and senescence regulation mechanisms. This study provides research directions for the development of postharvest storage and preservation technology. [ABSTRACT FROM AUTHOR]

【Objective】The study aims to explore the change law of fruit quality of the main citrus varieties in Ruili area of Yunnan Province during maturity, offering a theoretical foundation for identifying the appropriate time for fruit harvesting. 【Method】Four citrus varieties including Orah, Bingtang, Murcott, and W·Murcott were used as tested materials. Fruits were harvested 150-330 d after flowering (August 12, 2020 to February 8, 2021) and 240-405 d after flowering (November 8, 2021 to April 28, 2022). Samples were taken every fifteen days routinely, and the quality of the fruits was determined.【Result】 The single fruit quality and the fruit horizontal and longitudinal diameters of the four citrus varieties exhibited a trend of growing first and then flattening as the maturity of fruits. Orah, Bingtang, Murcott and W·Murcott fruits terminated their rapid growth and expansion period before 270, 255, 300 and 285 days after flowering, respectively. In a span of two years, except for Murcott (with transition period being consistent in the first and the second year), the color transition period of W·Murcott peel was earlier in the first year, and the color transition period of Orah and Bingtang was later than the first year. Bingtang, Orah, Murcott and W·Murcott all showed stable mass fractions of total soluble solids content (TSS) after 240, 315, 300 and 270 days of flowering, respectively; while the mass fractions of titratable acid content (TA) showed no significant change at 180, 210, 240 and 240 d of flowering, respectively.【Conclusion】Combining the indicators such as single fruit weight, horizontal and longitudinal diameter, peel colour, and mass fraction of internal substance content, the fruits of Orah, Bingtang, Murcott, and W·Murcott reach harvest maturity at 315, 255, 300, and 285 d after flowering, which are suitable for harvesting. [ABSTRACT FROM AUTHOR]

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To solve the problem of taste loss of new retail prepared fish after freezing and reheating. The changes of moisture content, water holding capacity, water distribution, and microstructure in pre-fried fish were analyzed during frying, freezing and reheating processes. The results showed that with the increase of freezing-thawing cycles, a significant decrease of the moisture content (P

In order to study the quality change of coffee malt premixed powder with the extension of storage period, the coffee malt premixed powder was stored at the environment where the temperature is 25 ℃ and 35 ℃, respectively, and the relative humidity is 50% respectively. Its moisture, fatty acid value and falling value were monitored during the whole storage period. The volatile compounds were separated and identified by solid phase microextraction accompanying gas chromatography-mass spectrometry during the whole storage period. The results demonstrated that with the extension of storage period, the overall moisture content shows a falling trend, while the fatty acid value and falling value show an overall rising trend. The higher the storage temperature, the more significant the change is 41 kinds of main volatile compounds of coffee malt ready mixed powder were identified. It mainly includes 13 kinds of aldehydes, 15 kinds of heterocycles, 7 kinds of esters, 4 kinds of alcohols and 2 kinds of ketones. Among them, the relative concentration of aldehydes (n-hexanal, nonanal, trans-2-nonenal) showed an increasing trend with the extension of storage period.

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The changes in the qualities and sweet-substance levels of Junzao jujube during variable-temperature drying (VTD) were investigated. The results showed that VTD retains the original color of jujube, reduces its hardness and chewiness, and decreases its wrinkling while shortening the drying time by 13.2% compared with that of constant temperature drying (CTD). “Electronic-tongue” taste analysis showed that the sweetness of VTD jujube is significantly higher than that for CTD. This is shown to be related to the contents of sucrose, fructose, and glucose, as well as the activities of invertase and sucrose synthase enzymes. In addition, the content trends for sweet amino acids are correlated with the temperature gradient used in VTD. Thus, the present study elucidates the factors governing the transformation of sugar substances in jujube during VTD, as well as providing a practical reference for the application of VTD in the jujube industry.

To investigate the effects of traditional high-temperature cooking and sous-vide cooking on the quality of tilapia fillets, muscle microstructure, texture, lipid oxidation, protein structure, and volatile compounds were analyzed. In comparison with samples subjected to traditional high-temperature cooking, sous-vide-treated samples exhibited less protein denaturation, a secondary structure dominated by α-helices, a stable and compact structure, a significantly higher moisture content, and fewer gaps in muscle fibers. The hardness of the sous-vide-treated samples was higher than that of control samples, and the extent of lipid oxidation was significantly reduced. The sous-vide cooking technique resulted in notable changes in the composition and relative content of volatile compounds, notably leading to an increase in the presence of 1-octen-3-ol, α-pinene, and dimethyl sulfide, and a decrease in the levels of hexanal, D-limonene, and methanethiol. Sous-vide treatment significantly enhanced the structural stability, hardness, and springiness of muscle fibers in tilapia fillets and reduced nutrient loss, enriched flavor, and mitigated effects on taste and fishy odor. [ABSTRACT FROM AUTHOR]

Flos Sophorae (FS), or the dried flower buds of Sophora japonica L., is widely used as a food and medicinal material in China. The quality of S. japonica flowers varies with the developmental stages (S1-S5) of the plant. However, the relationship between FS quality and maturity remains unclear. Inductively coupled plasma optical emission spectrometry (ICP-OES) and ultra-high performance liquid chromatography coupled with electrospray ionization-triple quadrupole-linear ion trap mass spectrometry (UPLC-ESI-Q TRAP-MS/MS) were used to analyze inorganic elements and flavonoid metabolites, respectively. A combined analysis of the inorganic elements and flavonoid metabolites in FS was conducted to determine the patterns of FS quality formation. Sixteen inorganic elements and 173 flavonoid metabolites that accumulated at different developmental stages were identified. Notably, 54 flavonoid metabolites associated with the amelioration of major human diseases were identified, and Ca, P, K, Fe, and Cu were postulated to influence flavonoid metabolism and synthesis. This study offers a novel perspective and foundation for the further exploration of the rules governing the quality of plant materials. [ABSTRACT FROM AUTHOR]

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Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To investigate the effect of Nisin on the storage of roasted shrimp with high water content at room temperature, different concentrations of Nisin (20, 60 and 100 mg/kg) were added to the rosted shrimp samples. Sensory evaluation combined with the total viable count (TVC), the Bacillus cereus count, the total volatile basic nitrogen (TVB-N) and the pH value were used as indicators, to evaluate the quality of rosted shrimp samples. The results showed that the sensory evaluation scores decreased during storage of samples, and the TVC, the Bacillus cereus count, the TVB-N and the pH value of the samples increased gradually. With the increase of added Nisin, the growth of the TVC, the Bacillus cereus count and the TVB-N slowed down. On the 6th day, the TVC of the control group reached the threshold specified in the Chinese industry standard "Seasoned roasted shrimp" (3×104 CFU/g), while the shelf life of samples with 20, 60 and 100 mg/kg Nisin were extended to 8, 12 and 14 days, respectively. This study showed that Nisin had an inhibitory effect on the growth of microorganisms such as Bacillus cereus in the roasted shrimp with high water content, and it could effectively prolong the shelf life of the product.

Highly prized for its unique taste and appearance, pitaya is a tasty, low-calorie fruit. It has a high-water content, a high metabolism, and a high susceptibility to pathogens, resulting in an irreversible process of tissue degeneration or quality degradation and eventual loss of commercial value, leading to economic loss. High quality fruits are a key guarantee for the healthy development of economic advantages. However, the understanding of postharvest conservation technology and the regulation of maturation, and senescence of pitaya are lacking. To better understand the means of postharvest storage of pitaya, extend the shelf life of pitaya fruit and prospect the postharvest storage technology, this paper analyzes and compares the postharvest quality changes of pitaya fruit, preservation technology, and senescence regulation mechanisms. This study provides research directions for the development of postharvest storage and preservation technology.

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to explore the changes in the quality of ready-to-eat peeled shrimp (Solenocera crassicornis) during chilled storage. The cooked shrimp were soaked in hermetically sealed jars, which were treated by three soaking methods: distilled water; 4% NaCl solution; and 4% NaCl, 0.34% citric acid, 4.23% trehalose, and 0.04% VC solution (defined as the control, experimental 1 (E1), and experimental 2 (E2) groups, respectively). The shelf-life of the E2 group was 20 days longer than that of the control group. Sensory scores, color, and textural results confirmed the E2 group exhibited better sensory scores and color, and the degradation of the physical structure of shrimp muscle was delayed during chilled storage. In addition, the total volatile basic nitrogen (TVB-N), total viable count (TVC), and thiobarbituric acid reactive substances (TBARS) of shrimp muscle in each group all showed an increasing trend, but these values were significantly lower in the E2 group than those in the control and E1 groups during chilled storage. The results of gas chromatography–ion mobility spectrometry (GC–IMS) and principal components analysis (PCA) showed that the volatile organic compounds (VOCs) in the three groups of RTE shrimp muscle changed, but small changes in VOCs were observed in E2 during chilled storage. These results provide new ideas and references for peeled shrimp product development and quality assurance technology. [ABSTRACT FROM AUTHOR]

为了对中包装的大豆油棕榈油煎炸专用调和油配方的开发和煎炸稳定性相关理化指标的选择提供参考，分别以一级大豆油、分提18 ℃棕榈油（一次精炼）及同批次的二次精炼18 ℃棕榈油为煎炸油，模拟薯条在180 ℃下高温煎炸32 h，对3种油品在煎炸过程中的酸值、过氧化值、p-茴香胺值、脂肪酸组成、极性组分含量、生育酚含量等理化指标进行了检测，并对18 ℃棕榈油中的风险因子，如PAH4、苯并（a）芘、3-氯丙醇酯（3-MCPDE）、反式脂肪酸含量进行了分析。结果表明：3种油品的酸值、过氧化值在煎炸过程中变化不明显，而p-茴香胺值、脂肪酸组成、极性组分含量在煎炸过程中变化比较明显；3种油品的生育酚氧化速度总体偏差不大；分提18 ℃棕榈油、二次精炼18 ℃棕榈油中的苯并（a）芘、反式脂肪酸含量均随煎炸时间延长呈缓慢升高的趋势；二次精炼18 ℃棕榈油的3-MCPDE在未煎炸时远高于分提18 ℃棕榈油的，3-MCPDE在煎炸初期降解剧烈，最终达到平衡；分提18 ℃棕榈油与二次精炼18 ℃棕榈油在煎炸稳定性方面没有明显区别，二次精炼不仅损失了部分有益的微量营养成分（如生育酚），还伴生出新的风险因子，如增加了3-MCPDE、反式脂肪酸。综上，酸值、过氧化值不能作为评价煎炸稳定性的敏感指标，而p-茴香胺值、脂肪酸组成、极性组分含量可作为敏感指标联合应用于评价煎炸油煎炸稳定性，另外，应倡导适度加工，以降低精炼过程营养成分的损失，同时避免风险因子的生成。 In order to provide a reference for the development of the formulation of a medium-packed special blend oil soybean oil and palm oil for frying and the selection of physicochemical indexes related to the stability of frying, soybean oil, fractionated 18 ℃ palm oil (primary refining) and secondary refined 18 ℃ palm oil from the same batch were used as frying oils to simulate the frying conditions of French fries at a high temperature of 180 ℃ for 32 h, and the physicochemical indexes of the three oils during frying such as acid value, peroxide value, p-anisidine value, fatty acid composition, polar fraction content and tocopherol content were investigated. In addition, risk factors such as PAH4, benzo(a)pyrene, 3-chloropropanol ester (3-MCPDE) and trans fatty acids in the 18 ℃ palm oil were also analyzed. The results showed that the acid value and peroxide value of the three oils did not change significantly during frying, while p-anisidine value, fatty acid composition and polar fraction content changed significantly, and the oxidation rate of tocopherols did not deviate significantly overall. The benzo(a)pyrene and trans fatty acids contents in the fractionated 18 ℃ palm oil and the secondary refined 18 ℃ palm oil showed a slow increase trend. The 3-MCPDE content of the secondary refined 18 ℃ palm oil was much higher than that of the fractionated 18 ℃ palm oil at the time of unfrying, and the 3-MCPDE degraded dramatically at the beginning of frying and eventually reached equilibrium. There was no significant difference in frying stability between fractionated 18 ℃ palm oil and secondary refined 18 ℃ palm oil, and secondary refining not only could lose some beneficial micronutrients (e.g. tocopherols), but also could generate new risk factors, such as an increase in 3-MCPDE and trans fatty acids. In conclusion, the acid value and peroxide value can not be used as sensitive indicators for frying stability of frying oils, while p-anisidine value, fatty acid composition and polar fraction content can be used as sensitive indicators for frying stability of frying oils. In addition, moderate processing should be advocated to reduce the loss of nutrients during refining and to avoid the generation of risk factors.

To investigate the effect of different packaging methods on the quality characteristics of buffalo meat during refrigerated storage, buffalo meat was used as raw material, and meat samples were packaged with pallet packaging, film-coating with pallet packaging, vacuum packaging, respectively, and then stored at 4 ℃. The quality indicators, including the color, pH, centrifugal loss, cooking loss, volatile basic nitrogen (TVB-N), carbonyl content, total number of colonies and the number of coliforms, etc. were analyzed. The results showed that with the extension of the refrigeration time，the L* and a* values of buffalo meat with three packaging methods continued to decrease, but the cooking loss, b* value, volatile basic nitrogen, carbonyl content, total number of colonies and number of coliforms continued to increase, and the pH and centrifugal loss showed a dynamic change trend of first decline and then rise. The TVB-N value of the pallet packaging group reached 17.56 mg/100 g at the 6th day of cold storage, the TVB-N value of the film-coating with pallet packaging group reached 19.17 mg/100 g at the 10th day of cold storage, and the TVB-N value of the vacuum packaging group reached 16.20 mg/100 g at the 15th day of cold storage, exceeding the national standard limit (15 mg/100 g). Among the three packaging methods, vacuum packaging could not only maintain the color and water holding capacity of buffalo meat, decrease TVB-N, the total number of colonies and the number of coliforms, but also effectively inhibit the protein oxidation. Therefore, vacuum packaging had the best effect on maintaining the quality of buffalo meat, and its fresh-keeping effect was better than that of pallet packaging and film-coating with pallet packaging.

The effects of NaCl concentrations (0%, 2%, 4% and 6%) on the changes in muscle quality of ready-to-eat shrimp (Solenocera crassicornis) were investigated during 50 days of chilled storage. During 0~50 day of chilled storage, the color, texture, moisture content, water-holding capacity, pH, total volatile base nitrogen (TVB-N) content, total bacterial count, TBA values, and histological changes were determined in the shrimp muscle tissues pre-treated with different NaCl solutions. The results showed that 4% and 6% NaCl treatments significant (P

In order to explore the quality changes of grass carp visceral fish oil under different storage temperatures, the grass carp visceral fish oil was extracted by enzymatic method. The visceral fish oil of grass carp was stored at cold storage (4 ℃), normal temperature (25 ℃) and 37 ℃ for 60 days at constant temperature, and its acid value and peroxide value were determined regularly. Fingerprint characteristic analysis, principal component analysis (PCA) and linear discriminant analysis (LDA) and load analysis and other electronic nose technologies regularly were used to analyze the changes of volatile components. The results showed that the changes of acid value, peroxide value and volatile odor components of grass carp viscera were not obvious during storage at low temperature (4 ℃); The acid value and peroxide value of grass carp visceral crude oil increased significantly at room temperature (25 ℃) and 37 ℃, and the volatile odor components changed significantly, especially at 37 ℃; Taking the acid value and peroxide value as the criteria for judging whether the fish oil was deteriorated, the shelf life was about 55 days at 4 ℃, 40 days at 25 ℃ and 30 days at 37 ℃; The volatile components of fish oil during storage were mainly nitrogen oxides, sulfides and aromatic components. This study provides a theoretical basis for the effective utilization of grass carp viscera.

In this study, electrolyzed water (EW), which is being used for disinfection in various food production applications, is discussed. Today, research on green production has intensified, aiming to preserve food for a longer time, using fewer chemicals or none, in order to preserve the initial nutritional properties of the food and deliver it to the consumer. In this context, it is an undeniable fact that there is a need to improve existing methods and practices and develop new technologies for the long-term storage of foods without quality losses and health concerns. One of the methods developed for this purpose is the use of electrolyzed water in food disinfection. While the use of electrolyzed water in various stages of the food processing industry creates a relatively new field of application, many studies have focused on its antimicrobial and antioxidant activity. However, studies on the use of this method in the fish processing industry are very limited and need to be developed. Previous studies are mainly related to the antimicrobial properties of electrolyzed water and there are limited studies on the effects of seafood products on storage times (shelf life). However, in light of the studies, it is seen that electrolyzed water has potential uses for the seafood processing industry.

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Copyright of Chinese Journal of Oil Crop Sciences is the property of Oil Crops Research Institute of Chinese Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The nutritional composition, physicochemical indexes and harmful substance contents of flaxseed oil during frying process under conventional frying condition were studied in this paper, and its frying performance was comprehensively analyzed by principal component analysis. The results showed that the unsaturation of flaxseed oil without frying was 81.77%. The content of α-linolenic acid was 47.50%, which was a kind of high nutritional value edible oil. During the 60 h (5 d)170 ℃ continuous frying, the color, acid value, peroxide value, refractive index, carbonyl value, polar components, tocopherol content and fatty acid composition of flaxseed oil changed significantly (P

Taking large yellow croaker roe fermented fish sauce as the research object, analyzed the influence of the amount of koji, the amount of salt added, and the temperature in the fermentation process on the pH of fish sauce, total acid, amino acid nitrogen, volatile base nitrogen, fat, thiobarbituric acid and other physical and chemical indicators. And the content of amino acids at the 30th day of fermentation was analyzed. The results showed that during the fermentation process of large yellow croaker roe and fish sauce, the pH fluctuated during fermentation, and the change of total acid content was consistent with it. The amino acid nitrogen content in the fermentation process showed an upward trend, and the amino acid nitrogen content in the 15% fermented koji was higher than the 10% and 20% koji. The volatile base nitrogen showed an upward trend. Moreover, the volatile base nitrogen of fermented fish sauce under 15% salt content and 35 ℃ was much lower than that of 10% salt content and 40 ℃ fermentation conditions. The fat content showed a downward trend. The thiobarbituric acid content fluctuated slightly in the early stage and raised in the final stage. The contents of free amino acids under different fermentation conditions were compared. Therefore, 15% salt addition, 15% koji addition, and 35 °C were the best fermentation process conditions for large yellow croaker roe and fish sauce.

The quality changes of rose low-nitrate semi-dry fermented sausage (M) and traditional semi-dry fermented sausage (P) during storage at 3 temperatures (4, 25, 35 °C) were evaluated in this study. Then, the kinetic and the Arrhenius equation were used to establish the prediction models for the shelf life of fermented sausages. Studies had shown that temperature had a greater impact on the redness value and texture characteristics of the two groups of sausages. During storage, the acid value, total volatile basic nitrogen (TVB-N) value and total viable count (TVC) at each storage temperature increased with the storage time, and the higher temperature, the more obvious the change trend. The kinetic model was established with TVB-N value and TVC as the key factors, and combined with the Arrhenius equation, the shelf life prediction models of two fermented sausages were constructed. In the TVB-N and TVC prediction models of fermented sausage P, the activation energy Ea was 52.37 kJ/mol and 43.39 kJ/mol, respectively, and the pre-explicit factor K0 was 69859734.72 and 8800494.34, respectively. In the TVB-N and TVC prediction models of fermented sausage M, the activation energy Ea was 46.46 kJ/mol and 43.53 kJ/mol, respectively, and the pre-exponential factor K0 was 5373553.61 and 8016399.99, respectively. 4 ℃ and 30 ℃ were selected as the verification temperature to test the reliability of the shelf life prediction model. The results showed that the relative error between the theoretical and measured shelf life of the two fermented intestines was within 11.18%, and could be used for shelf life prediction in the temperature range of 4 to 35 ℃. In addition, the quality of fermented sausage M was better than that of fermented sausage P, and had a longer shelf life.

To investigate the effects of traditional high-temperature cooking and sous-vide cooking on the quality of tilapia fillets, muscle microstructure, texture, lipid oxidation, protein structure, and volatile compounds were analyzed. In comparison with samples subjected to traditional high-temperature cooking, sous-vide-treated samples exhibited less protein denaturation, a secondary structure dominated by α-helices, a stable and compact structure, a significantly higher moisture content, and fewer gaps in muscle fibers. The hardness of the sous-vide-treated samples was higher than that of control samples, and the extent of lipid oxidation was significantly reduced. The sous-vide cooking technique resulted in notable changes in the composition and relative content of volatile compounds, notably leading to an increase in the presence of 1-octen-3-ol, α-pinene, and dimethyl sulfide, and a decrease in the levels of hexanal, D-limonene, and methanethiol. Sous-vide treatment significantly enhanced the structural stability, hardness, and springiness of muscle fibers in tilapia fillets and reduced nutrient loss, enriched flavor, and mitigated effects on taste and fishy odor.

In order to deeply study the quality change characteristics of different tissues of boiled mutton during low-temperature storage, the lean meat, fat lean phase and fat meat part of boiled mutton were used as the main raw materials. The changes of pH, texture characteristics, color difference, total volatile base-nitrogen (TVB-N), total number of colonies and sensory evaluation were studied during its storage at 4 ℃ or low temperature for 28 days (samples were taken every 1 week) by vacuum packaging. The results showed that the pH value of different tissues of cooked mutton decreased first and then increased when stored at 4 ℃. The texture characteristics of fat meat were higher than those of lean meat and fat lean meat. During storage, the L* value and a* value of different tissues of mutton decreased gradually (P

After-ripening is one of the characteristics of grain, physiological and biochemical activities will exist in grain during this period. Its processing quality and edible quality will generally be improved after the completion of ripening. However, there are few studies on after-ripening of rice, one of the main grain crops in China. The physiological and biochemical indexes (germination rate, conductivity, roughness and fatty acid value), gelatinization characteristics and different enzyme activities (peroxidase, catalase, α-amylase) of six types of high-quality indica rice (Longliangyou 534, Huanghuazhan, Yingxiangsimiao, Yuenongsimiao, Xiadao 1 and Ayou 442) were measured regularly during after-ripening period to investigate the after-ripening duration of indica rice, the specific activity state during the after-ripening period and the quality change rules during after-ripening period of indica rice. The results showed that six kinds of high quality indica rice had different after-ripening duration, 6 varieties at ripening time of germination rate rose on the whole, the conductivity was fluctuating downward trend after rising first, out of the roughness increased volatility, the fatty acid value decreased firstly then increased, peroxidase varieties had differences in trends but volatility declined on the whole, the activity of catalase showed a fluctuating upward trend except Ayou 442, the activity of α-amylase showed a fluctuating downward trend except Huanghuazhan, and the peak viscosity showed a fluctuating upward trend at first and then a decreasing trend. The quality evaluation was carried out by principal component analysis, and the scores from high to low were Ayou 442, Longliangyou 534, Xiadao 1, Yuenongsimiao, Yingxiangsimiao, Huanghuazhan.

This paper aimed to explore the effect of Lactobacillus plantarum microcapsules fermentation on the quality of carrot chips, and the change of viable cell count under freeze-drying and simulated gastric juice conditions. In this study, Lactobacillus plantarum microcapsules were prepared by extrusion method using sodium alginate and isolated whey protein as wall materials. The carrot chips fermented with Lactobacillus plantarum microcapsules were used as experimental group and the carrot chips fermented without microcapsules were used as control group. The results showed that there were no significant differences in texture, color, total sugar content, carotene content and ascorbic acid content between test group and control group (P>0.05). In freeze-drying and simulated gastric juice environment, the number of viable bacteria in the test group was significantly higher than that in the control group, which remained (8.47±0.02) and (8.31±0.01) lg(CFU/g), respectively. Microencapsulated Lactobacillus plantarum fermentation had no prominent effect on the quality of carrot chips and could improve the resistance of Lactobacillus plantarum to adverse environments (such as freeze-drying and gastric juice).

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Hot air drying is the most common processing method to extend shrimp's shelf life. Real-time monitoring of moisture content, color, and texture during the drying process is important to ensure product quality. In this study, hyperspectral imaging technology was employed to acquire images of 104 shrimp samples at different drying levels. The water distribution and migration were monitored by low field magnetic resonance and the correlation between water distribution and other quality indicators were determined by Pearson correlation analysis. Then, spectra were extracted and competitive adaptive reweighting sampling was used to optimize characteristic variables. The grey-scale co-occurrence matrix and color moments were used to extract the textural and color information from the images. Subsequently, partial least squares regression and least squares support vector machine (LSSVM) models were established based on full-band spectra, characteristic spectra, image information, and fused information. For moisture, the LSSVM model based on full-band spectra performed the best, with residual predictive deviation (RPD) of 2.814. For L*, a*, b*, hardness, and elasticity, the optimal models were established by LSSVM based on fused information, with RPD of 3.292, 2.753, 3.211, 2.807, and 2.842. The study provided an in situ and real-time alternative to monitor quality changes of dried shrimps. [ABSTRACT FROM AUTHOR]

Gardenia erubscens fruits have been identified as a valuable source of nutrients and antioxidants, which are beneficial for human health. To preserve the nutritional properties of fruits after drying, appropriate packaging material should be considered. The objective of this study was to explore the effects of different packaging materials namely high-density polyethylene, low-density polyethylene, single-layer polyethylene, double-layer polyethylene and laminated paper bags on moisture content (MC), water activity (aw), pH, color, ß-carotene, vitamins A and C, and microbial load of dried G. erubscens fruit and powder. The samples were stored under ambient conditions for 12-weeks. The results showed that MC and aw of the dried fruits and powder increased while pH decreased as the storage progressed irrespective of the packaging material type. The redness (a*), yellowness (b*) and total color change (ΔE*) values of both dried fruits and powder were significantly (p

Objective: This study aimed to investigate the effects of different concentrations of preservatives on storage quality of orah fruits, so as to reduce the use of preservatives during its planting. Methods: The weight loss rate, vitamin C content, soluble solid content and titratable acid content of fruits were determined under different storage conditions, by using different concentrations of preservative. Results: At 4 ℃ and room temperature, the weight loss rate of fruits treated with preservatives was lower than that of the control group, and preservative treatment had different fresh-keeping effects on orah fruits. At 4 ℃, significant differences in vitamin C content among different treatments at 5, 28 and 42 days of storage were found, but no significant differences in other storage time. No significant difference in soluble solids and titratable acid contents among different treatments appeared. Among the treatment groups (treatment 1, treatment 2 and treatment 3), the weight loss rate, vitamin C content, soluble solid content and titratable acid content of orah fruit in treatment 2 were better than those in treatment 1 and 3. At room temperature, vitamin C content was significantly different among different treatments on the third day of storage. After 14 days of storage, the soluble solid content of treatment groups 1 and 2 was significantly different. On the 14th day of storage time, titratable acid content in treatment group 2 was significantly higher than that in treatment group 3. The contents of vitamin C, soluble solids and titratable acid in treatment group 2 were higher than those in other treatment groups, during most storage time. Conclusion: At 4 ℃, each preservative treatment has different degrees of preservation effect on orah fruits. 450 g/L midazamine +500 g/kg statin +100 g/kg 2,4-D+400 g/kg bellkute has better preservation effect on orah fruit.

This study aimed to explore the changes in the quality of ready-to-eat peeled shrimp (Solenocera crassicornis) during chilled storage. The cooked shrimp were soaked in hermetically sealed jars, which were treated by three soaking methods: distilled water; 4% NaCl solution; and 4% NaCl, 0.34% citric acid, 4.23% trehalose, and 0.04% VC solution (defined as the control, experimental 1 (E1), and experimental 2 (E2) groups, respectively). The shelf-life of the E2 group was 20 days longer than that of the control group. Sensory scores, color, and textural results confirmed the E2 group exhibited better sensory scores and color, and the degradation of the physical structure of shrimp muscle was delayed during chilled storage. In addition, the total volatile basic nitrogen (TVB-N), total viable count (TVC), and thiobarbituric acid reactive substances (TBARS) of shrimp muscle in each group all showed an increasing trend, but these values were significantly lower in the E2 group than those in the control and E1 groups during chilled storage. The results of gas chromatography–ion mobility spectrometry (GC–IMS) and principal components analysis (PCA) showed that the volatile organic compounds (VOCs) in the three groups of RTE shrimp muscle changed, but small changes in VOCs were observed in E2 during chilled storage. These results provide new ideas and references for peeled shrimp product development and quality assurance technology.

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Official rentals for housing (rent) price inflation statistics are of considerable public interest. Matched-sample estimators, such as that used for nearly two-decades in New Zealand (2000–2019), require an unrealistic assumption of a static universe of rental properties. This article investigates (1) a property fixed-effects estimator that better reflects the dynamic universe of rental properties by implicitly imputing for price change associated with new and disappearing rental properties; (2) length-alignment simulations and property life-cycle metrics to inform the choice of data window length (eight years) and preferred splice methodology (mean-splice); and (3) stock-imputation to convert administrative data from a 'flow' (new tenancy price) to 'stock' (currently paid rent) concept. The derived window-length sensitivity findings have important implications for inflation measurement. It was found that the longer the data window used to fit the model, the greater the estimated rate of inflation. Using administrative data, a range of estimates from 55% (window length: three-quarters) to 127% (window of 90-quarters) were found for total inflation, over the 25-years to 2017 Q4. [ABSTRACT FROM AUTHOR]

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The effects of modified atmosphere packaging (MAP) and transportation conditions on the quality of fresh-cut (FC) purple cabbage during cold-chain transportation at 4°C for 20 days were investigated. The weight loss and respiratory intensity of FC purple cabbage were found to be significantly prevented and inhibited, measuring from 0% and 5.92 mg CO2 kg−1 h−1 to 3.47% and 5.05 mg CO2 kg−1 h−1, respectively, at the end of storage, through the use of argon-MAP and shock-absorbing packing material during transportation. Furthermore, the contents of vitamin C (VC) and total soluble solids (TSS) also decreased in the FC cabbage, to 21.6 mg 100g−1 FW and 13.88%, respectively. Additionally, the polyphenol oxidase (PPO) activity and total phenol (TP) content of the treated purple cabbage were inhibited effectively. After storage for 20 days, the sensory comprehensive score, L*, a*, and b* values of the processing group 10 were 8.5, 6.82, 5.55 and 1.54, respectively. These results demonstrate that the combined treatment of argon-MAP and shock-absorbing transportation can be considered efficient in preserving the quality of FC purple cabbage during storage.

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hot air drying is the most common processing method to extend shrimp’s shelf life. Real-time monitoring of moisture content, color, and texture during the drying process is important to ensure product quality. In this study, hyperspectral imaging technology was employed to acquire images of 104 shrimp samples at different drying levels. The water distribution and migration were monitored by low field magnetic resonance and the correlation between water distribution and other quality indicators were determined by Pearson correlation analysis. Then, spectra were extracted and competitive adaptive reweighting sampling was used to optimize characteristic variables. The grey-scale co-occurrence matrix and color moments were used to extract the textural and color information from the images. Subsequently, partial least squares regression and least squares support vector machine (LSSVM) models were established based on full-band spectra, characteristic spectra, image information, and fused information. For moisture, the LSSVM model based on full-band spectra performed the best, with residual predictive deviation (RPD) of 2.814. For L*, a*, b*, hardness, and elasticity, the optimal models were established by LSSVM based on fused information, with RPD of 3.292, 2.753, 3.211, 2.807, and 2.842. The study provided an in situ and real-time alternative to monitor quality changes of dried shrimps.

Five thawing methods such as flow water thawing, ultrasonic flowing water thawing, air thawing, microwave thawing and low temperature thawing were used, and the physical, chemical properties and structure of mackerels after thawing were assessed. The results showed that the low temperature thawing had the best water retention, lower protein and fat oxidation. The microwave thawing had the shortest thawing time, but uneven heating leads to partial maturation. Air thawing prolonged exposure to air leads to high levels of protein and fat oxidation. The flow water thawing had better water retention than that of the ultrasonic flowing water thawing, only the thawing time was slightly longer than that of the ultrasonic flowing water thawing. In general, the low temperature thawing performed well after thawing. The flow water thawing used only 1/43 of the low temperature thawing's elapsed time after sacrificing some acceptable qualities. Thus, flow water thawing is more suitable for thawing frozen mackerel. [ABSTRACT FROM AUTHOR]