Higher Sensory Scores Research Articles

Effect of chitosan-coated Ulva intestinalis sulfated polysaccharide nanoliposome on melanosis and quality of Pacific white shrimp during ice storage

This study investigates chitosan coating containing nanoliposome of Ulva intestinalis sulfated polysaccharide, its effect on melanosis, as well as the quality of Pacific white shrimp during 20 days of storage in ice. The sulfated polysaccharide was extracted from Ulva intestinalis (USP), and its impact on the shrimp's polyphenol oxidase (PPO) enzyme inhibition in different concentrations was measured. The optimum concentration of USP with the highest inhibition percentage was selected and used. USPs were loaded in nanoliposome or coated in chitosan then shrimps were immersed in these coatings. 1.5 % USP showed the highest inhibitory effect of PPO enzyme after 1 and 3 min with values of 63.03 % and 48.74 %. The melanosis of shrimps with different types of USP coating was significantly lower than the control. The lowest color change (ΔE), total viable counts (TVC) bacterial, TVN content, and weight loss were achieved in the Ch-USP treatment. The highest sensory score was found in the Ch-N-USP treatment. This coverage delayed the increase of psychrophilic bacteria (PBC) and chemical tests (TBA, FFA, and PV). Therefore, Ch-USP and Ch-N-USP treatments can be used as a natural substitute for sodium metabisulfite to increase the shelf life and shrimp quality during ice storage.

Effects of heat treatment, plant coagulant, and starter culture on sensory characteristics and volatile compounds of goat cheese

The effects of heat treatment, coagulant source, and starter culture addition on the physicochemical, sensory characteristics, and volatile compounds of goat cheese were evaluated. For this purpose, the goat cheese was produced from raw milk or heat-treated milk coagulated with Cynara cardunculus L. protease or calf rennet. The effect of the starter culture addition was also investigated. No significant differences were observed between the cheeses produced using different coagulants in terms of chemical, microbiological and sensory parameters, and proteolysis levels, but the combination of heat treatment and starter culture addition affected most of the attributes. A total of 27 volatile compounds, including acids, alcohols, esters, ketones, and aldehydes, were identified in the cheeses during ripening. Acidic compounds were the most abundant volatiles in cheeses. The raw milk cheeses had the highest sensory scores, while an unpleasantly bitter taste was recorded for the heat-treated and starter-free milk cheeses.

Physicochemical characteristics of meat from capons derived from the crossing of conserved breed hens and meat roosters

The study aimed to determine the effect of castration on physicochemical properties of meat from capons derived from the crossing of Rhode Island Red (R-11) hens and meat roosters. Subjects were 100 crossbred cockerels, which were randomly assigned to 2 groups of 50 each. Group I (control) consisted of intact cockerels and birds from group II were subjected to castration. The castration was performed at 7 wk of age under local anesthesia by a veterinarian. All birds were fed ad libitum with the same feed mixtures and placed on litter under optimal environmental conditions at a stocking density of 5 birds/m2. At the end of fattening (20 wk of age), 10 birds whose body weight was similar to group average, were selected from each group for slaughter. After slaughter, the birds were analyzed for dressing percentage and physicochemical parameters of breast and leg muscles, which were subjected to sensory evaluation. The results demonstrated that compared to intact cockerels, capons were characterized by significantly higher body weight, dressing percentage and carcass muscle content. Both the breast and leg muscles of the capons showed better physicochemical parameters and higher sensory score. It is therefore concluded that the birds derived from the crossing of Rhode Island Red (R-11) hens and meat roosters are good material for capon production, their meat is a product of distinctly higher quality.

Antioxidants and Quality Changes of Thermally Processed Purple Corn (Zea mays L.) Milk Fortified with Low Sucrose Content during Cold Storage.

Purple corn kernels were subjected to boiling and steaming times of 5-15 min to extract purple corn milk (PCM). Pasteurized and unpasteurized PCM samples were investigated for changes in anthocyanins, antioxidants, and physicochemical properties. Anthocyanins, total phenolics, antioxidant activity, color and viscosity values showed promising results in pasteurized PCM samples extracted from kernels steamed for 5 min (PPCM-S5) compared to other samples (p ≤ 0.05). Changes in L*, a* and b* values, total phenolics and DPPH activity were lowered in PPCM-S5 samples with higher retention of anthocyanins compared to the PCM extracted from boiled kernels (p ≤ 0.05). PCM extracted from 5 min steamed kernels fortified with 4% sucrose (PCM5-S4) after pasteurization revealed the lowest changes in color, pH, total soluble solid and viscosity during 12 days of storage at 4 °C compared to the unpasteurized PCM without sucrose and pasteurized PCM fortified with 6% sucrose. Additionally, pasteurized PCM5-S4 samples marked the highest anthocyanins, total phenolics and antioxidant activity during storage. Microbial load was lowest in pasteurized PCM5-S4 samples stored at 4 °C for 12 days. However, coliforms, yeast or mold and Escherichia coli were not present in the thermally processed PCM samples. The highest sensory scores were obtained in PCM5-S4 at day 12 of storage compared to PCM without any treatment. Therefore, pasteurized PCM extracted from 5 min steamed purple corn kernels retained bioactivity along with 4% sucrose fortification resulted in higher sensory acceptability. As a consequence the shelf-life of PCM5-S4 sample was extended up to 12 days at 4 °C.

The effect of aged pork fat on the quality and volatile compounds of Chi-aroma Baijiu

This study aimed to explore the effect of aged pork fat on the quality and volatile compounds of Chi-aroma Baijiu during the ageing stage. Result showed that glycerol and total ester contents of CBN, CB1, CB3 and CB5 were significantly higher than that in BL (P < 0.05), but total acid contents did not change significantly (P > 0.05). Moreover, there was a difference in volatile compounds concentration and OAVs among the Chi-aroma Baijiu samples. With the year of aged pork fat increased, concentrations of esters and aldehydes were increased and then decreased, which reached highest in CB1. CB1 had highest OAVs of medium and long-chain ethyl esters and four aldehydes ((E)-2-nonenal, octanal, (E)-2-decanal, (E)-2-octenal) were the characteristic volatile compounds of Chi-aroma Baijiu during ageing process owing to their OAV > 10. Therefore, CB1 had the highest sensory score, with intense Chi-aroma and pleasant aftertaste. OPLS-DA further effectively distinguish different Chi-aroma Baijiu soaking with different years of aged pork fat, and confirmed 31volatile compounds (especial ethyl esters) were the key volatile compounds responsible for significant differences in Chi-aroma Baijiu. Combined with the results of sensory evaluation, GC-MS and OAVs, one-year aged pork fat was the best to product Chi-aroma Baijiu.

Study on the antioxidant properties of Moringa oleifera leaf aqueous extract and its effect on the sensory attributes of raw and cooked Japanese quail meat

The study was conducted to standardise the concentration of Moringa leaf aqueous extract (MLE) as a natural antioxidant for applying on Japanese quail carcasses and its effect on the sensory attribute using semi-trained panellists. The concentration of the extract was selected initially on the basis of phytochemical and antioxidant activities of MLE. The total phenolics and flavonoid content of MLE was 72.16 ± 1.80mg GAE/mL and 12.65 ± 0.83 mg QE/mL of MLE. Analysis of the antioxidant activity of MLE was expressed in terms of IC50 (half maximal inhibitory concentration) value and four best concentrations having antioxidant activity greater than that of the IC50 concentration were selected. IC50 concentration obtained for MLE was 4.60 ±0.20 per cent and 5, 10, 15 and 20 per cents of MLE were selected, having antioxidant activities of 52.22± 1.09, 71.50± 2.23, 82.53± 1.84 and 87.30±1.46 per cents, respectively. Freshly prepared cold MLE solutions were used for dipping of quail carcass for five minutes against cold distilled water as negative control and cold water with synthetic antioxidants (BHA and BHT) as positive control. Sensory evaluation of the raw and cooked quail meat was conducted. No significant difference (p&gt;0.05) was observed. between treatments and controls in the sensory parameters of raw quail carcasses. But there was a significant (p&lt;0.05) difference in sensory attributes of cooked quail carcasses. Carcasses treated with 20 per cent MLE had lower flavour values and overall acceptability scores compared to other treatments and controls. The results indicated that dipping of quail carcasses in MLE (upto 15 per cent) had higher sensory scores and it can be used as a natural antioxidant without affecting the sensory quality.

Chestnuts in Fermented Rice Beverages Increase Metabolite Diversity and Antioxidant Activity While Reducing Cellular Oxidative Damage

Foods containing chestnuts (Castanea mollissima Blume) are relatively uncommon, despite the high nutrient and starch contents and purported health benefits. In this study, we examine the flavor-related metabolites, volatile compounds, and amino acids in a traditional glutinous rice fermented beverage supplemented with chestnuts as a fermentation substrate for lactic acid bacteria (LAB). Changes in antioxidant activity towards free radicals and effects on cellular oxidative stress are compared between beverages with or without chestnuts. The fermented chestnut-rice beverage (FCRB) has higher sensory scores and a wider range of volatiles and flavor-related compounds (74 vs. 38 species compounds), but lower amino acid contents, than the traditional fermented glutinous rice beverage (TFRB). In free radical scavenging assays, the FCRB exhibits higher activity than the TFRB in vitro. Furthermore, while neither beverage induces cytotoxity in Caco-2 cells at concentrations up to 2 mg/mL, pretreatment with the FCRB results in lower rates of apoptosis and necrosis and higher overall viability in cells with H2O2-induced oxidative stress compared to pretreatment with the TFRB. The enhanced reactive oxygen species neutralization in vitro and protection against oxidative damage in cells, coupled with increased diversity of volatiles and flavor-related metabolites of LAB, support the addition of chestnuts to enhance flavor profile and antioxidant properties of fermented functional foods.

Kappa-carrageenan-poly(vinyl alcohol) electrospun fiber mats encapsulated with Prunus domestica anthocyanins and epigallocatechin gallate to monitor the freshness and enhance the shelf-life quality of minced beef meat

The current study was conducted with the aim of fabricating k-carrageenan-poly(vinyl alcohol) (KC-PVA) electrospun fiber mats containing Prunus domestica extract (PDE; 3%) and epigallocatechin gallate (EGCG; 5 and 10 µg/ml) to monitor the spoilage and enhance the shelf-life quality of raw minced beef meat during prolonged chilled storage. The anthocyanin-rich electrospun fibers displayed color change when subjected to the different pH buffer solutions as follows: pH 1 = light pink; pH 2-5 = red; pH 6-8 = purplish-red; pH 9-10 = green; and pH 11-12 = brown. By incorporating PDE and PDE + EGCG into the KC-PVA electrospun fibers, tensile strength, water vapor permeability, moisture content, and water solubility decreased significantly, while thickness and elongation at break increased significantly compared to the control group (P < 0.05). Among different treatments, the lowest microbial and chemical changes and the highest sensory scores were found in the minced beef meat packaged with KC-PVA-EGCG 5 µg/ml-PDE 3% and KC-PVA-EGCG 10 µg/ml-PDE 3% electrospun fibers. At the end of the study (day 15), the total viable count, pH, and total volatile basic nitrogen of samples packaged with KC-PVA-PDE 3% electrospun fibers reached 7.21 log CFU/g, 6.63, and 28.07 mg N/100 g, respectively. In this group, the color of the electrospun fiber mats changed from white to purplish-red. Our findings indicate that the fabricated electrospun fibers with antimicrobial and antioxidant activities can be utilized as a smart packaging material for minced beef meat during refrigerated storage.

Effect of Nanoemulsion Containing Enterocin GR17 and Cinnamaldehyde on Microbiological, Physicochemical and Sensory Properties and Shelf Life of Liquid-Smoked Salmon Fillets.

The spoilage of liquid-smoked salmon represented a serious restriction for shelf life, due to the loss of taste, smell, color and consistency in product quality. The objective of this study was to investigate the feasibility of applying a nanoemulsion delivery system co-encapsulated enterocin Gr17 and essential oils (EOs) to the refrigerated storage of liquid-smoked salmon. The synergistic inhibiting effects of enterocin Gr17 and EOs were evaluated, a nanoemulsion delivery system with the optimal combination was developed, and the evolution of the microbiological, physicochemical, and sensory properties of liquid-smoked salmon fillets were analyzed during a 49-day period of refrigerated storage. The results showed that the combination of enterocin Gr17 and cinnamaldehyde essential oil (CEO) displayed the strongest synergistic inhibiting effect on foodborne pathogens. A nanoemulsion system incorporating enterocin Gr17 and CEO was successfully developed and presented a broad spectrum of activity against most of the tested bacteria. A nanoemulsion system incorporating enterocin Gr17 and CEO (CO-NE) could significantly inhibit the growth of microflora, suppress the accumulation of total volatile basic nitrogen (TVB-N) and thiobarbituric acid reactive substance (TBARS), and maintain better color, texture, and sensory profiles during smoked salmon storage at 4 °C. Overall, from a microbiological, physicochemical, and sensory point of view, the CO-NE treatment could extend the shelf life to 42 days and maintain the relatively low TVB-N value (≤15.38 mg/100 g), TBARS value (≤2.51 mg MDA/kg), as well as a relatively high sensory score (≥5.83) during the whole storage period. Hence, a nanoemulsion system incorporating enterocin Gr17 and CEO could be a promising bio-preservative technology and alternative to the conventional processes used for improving the safety and quality of chilled liquid-smoked salmon.

Development of mung bean (Vigna radiate L.)‐based next‐generation vegan milk: Processing, nutritional composition and quality attributes

SummaryLegume proteins are a potential source of functional ingredients to create good quality plant‐based milk substitutes. However, the design of high‐quality plant‐based milk substitutes depends on ingredients and processing operations. Thus, the objectives of the study were to investigate the effect of soaking, soaking and blanching, germination and germination and blanching in the development of high‐quality mung bean (Vigna radiate L.)‐based vegan milk. Also, studied the effect of processing methods on nutritional, physico‐chemical, sensory and microbiological analyses of the developed product. The sample with the germination method showed the highest protein (4.39%), carbohydrates (5.52%) and energy (39.93%) compared to other processing methods. The germination and blanching method reported a higher viscosity, sucrose content and TSS compared to other methods. All the samples showed a presence of 12 amino acids (e.g. glutamic acid, phenylalanine, serine) and absence of cystine and methionine. All the samples showed a decrease in pH and acidity, while no clot formation during the storage period. The presence of microbiological count was noticed from days 7 and 10, which remain under the acceptable standard limits. Germination &amp; blanching received a high sensory score and overall acceptability and provided the good quality attributes of mung bean‐based vegan milk. Thus, these processing technologies can be used to develop higher quality, healthiness and more sustainable vegan beverages that can substitute animal‐based milk.

Sensory characteristics of meat from rabbits fed concentrate diets containing Brassica oleracea outer leaves and Musa paradisiaca leaves

Two separate experiments were conducted to investigate the effect of incorporating levels of Brassica oleracea outer leaves and Musa paradisiaca leaves on sensory characteristics of rabbit meat. In each experiment, forty-eight (48) eight-week-old rabbits were randomly allotted to four treatments of concentrate diets with 0, 10, 20 and 30% inclusion levels of Brassica oleracea outer leaves and Musa paradisiaca leaves. Six rabbits were randomly selected from each treatment group and used for sensory evaluation at the end of a 12-week feeding period. Muscle samples were collected from the longissimus dorsi of the carcasses, pan-fried using 300 ml of Frytol® vegetable oil at 170ºC for 10 minutes. Thirty evaluators conducted the sensory evaluation according to the consumer acceptance and preference testing technique on a nine-point hedonic scale comprising appearance, flavour, colour, mouth-feel, taste, texture and overall acceptability. Generally, the sensory characteristic scores for the meat samples support the evaluators’ acceptability of the meat from rabbits fed the various diets. However, in specific terms, meat from rabbits fed diets containing 10 and 30% Brassica oleracea outer leaves and 20% Musa paradisiaca leaves tended to have higher sensory scores over meat from rabbits fed diets of the other inclusion levels of the leaves in the sensory attributes measured. The results of the study also suggest that feeding concentrate diets containing Brassica oleracea outer leaves and Musa paradisiaca leaves at 30% inclusion level resulted in the production of rabbit meat at a lower cost than feeding concentrate diets alone and acceptable to consumers.

Formulation of healthy cookies incorporated with orange peel powder and Moringa oleifera leaf powder

Studies were conducted for the incorporation of OPP (Orange peel powder) and MLP (Moringa leaves powder) in cookies. The OPP and MLP were analyzed and used in whole WF 100gm (0.5 gm, 1 gm, 1.5 gm, 2 gm, 2.5 gm, 3 gm, 3.5 gm, 4 gm) and MLP (0.5 gm, 1 gm, 1.5 gm 2 gm, 2.5 gm, 3 gm, 3.5 gm, 4 gm) proportion respectively. Based on sensory evaluation, 3% of OPP and 1% of MLP were selected for the preparation of healthy cookies. In the present work, OPP and MLP were prepared by using the tray dryer method. Jaggery and whole wheat flour were used instead of sugar and maida. The final formulation of the cookie mixture containing wheat flour (WF), OPP, and MLP was in the 96:3:1 ratio and resulted in the highest sensory score. The cookies were analyzed for various nutrients and phytochemical compounds. The utilization of waste orange peel and Moringa leaves was the most significant aspect of this study.

Comparison of potential Wickerhamomyces anomalus to improve the quality of Cabernet Sauvignon wines by mixed fermentation with Saccharomyces cerevisiae

Wine produced by mixed-yeast-starters of non-Saccharomyces strains and Saccharomyces cerevisiae proved to have distinctive aroma. To find more potential mixed-yeast-starters which can enhance sensory characteristics, five Wickerhamomyces anomalus strains were isolated in this paper. They were combined with S. cerevisiae respectively to co-ferment five wines. The aroma diversity and taste characteristics (intensity, astringency, complexity, and persistence) of three co-fermented wines were improved. Sc-WaG5 and Sc-WaG26 wines had higher concentrations of esters (acetate esters, ethyl esters and other esters). Sc-WaG27 wine showed highest contents of titratable acidity, total phenolic, total tannin and total anthocyanin. Additionally, it had higher level of norisoprenoids (ionone and damascenone), carbonyl compounds (2-octanone and nonanal), higher alcohols (isopentanol) and esters. Therefore, Sc-WaG27 wine possessed more complex aroma and highest sensory score. Our results highlighted that co-fermentation of the three W. anomalus strains with S. cerevisiae is a potential strategy to improve wine flavor and aroma, and enrich wine styles.

Molecular, Chemical, and Sensory Attributes Fingerprinting of Self-Induced Anaerobic Fermented Coffees from Different Altitudes and Processing Methods.

Coffee quality is achieved by performing good practices. This study aimed to evaluate coffees from different altitudes fermented with the self-induced anaerobic method (SIAF) and processed via natural (N) and pulped natural (PN). Molecular (PCR-DGGE), chemical (HPLC, ABTS, DPPH, ATR-FTIR, and GC-MS), and sensory analyses were performed. Leuconostoc predominated both processes and all altitudes. Hanseniaspora and Pichia predominated both processes at 800 and 1200 m. Acids were higher in N coffees for all altitudes. Acetic, malic acid and alcohols were the most abundant. Higher sensory scores were obtained in N (mainly at 1400 m-88.13). Floral and spices were perceived in all samples. ABTS capacity in roasted coffee increased with altitude in PN (2685.71, 2724.03, and 3847.14 µM trolox/g); meanwhile, the opposite was observed in N. High sensory scores were obtained in high altitudes. Alcohols and acids in roasted beans increase with altitude. Leuconostoc and Pichia showed potential as future coffee starters.

Growth kinetics, metabolomics changes, and antioxidant activity of probiotics in fermented highland barley-based yogurt

Fermenting yogurt with plant-based ingredients for nutritional and health benefits is an emerging trend. The growth kinetics, metabolomics changes, and antioxidant activity of probiotics in fermented highland barley-based yogurt were investigated in this study. Highland barley (HB) (Hordeum vulgare, Poaceae) enzyme hydrolyte was mixed with soy protein concentrate as ingredients for preparation of HB-based yogurt fermented by Lactobacillus bulgaricus VHProbi R03 and Streptococcus thermophilus VHProbi R08. After 4 h of fermentation, both strains grew to the stationary phase with the viable counts of 1.9 × 108 CFU/mL for each strain. The viable bacterial count in HB-based yogurt was approximately 9.3 × 107 CFU/mL after 21 days of storage at 4 °C. Compared with the control yogurt made using white sugar (as a substitute for HB enzyme hydrolyte) and soy protein concentrate, HB-based yogurt had higher concentrations of cyclic adenosine monophosphate, glycerophosphocholine, hypoxanthine and arginyl-proline, total phenolic compounds, and flavonoids, greater antioxidant activity, and higher sensory scores. In conclusion, HB-based yogurt is a potential novel food product that provides a good source of probiotics and antioxidants.

Manipulating the severe shoot topping delays the harvest date and modifies the flavor composition of Cabernet Sauvignon wines in a semi-arid climate

This study aimed to mitigate the adverse effects of global warming by applying severe shoot topping (SST) to grapevines in a semi-arid climate. A three-year study (2018–2020) was performed to investigate the impact of SST on wine flavor composition. Results showed that SST effectively delayed the grape harvest date, which was more evident in the dry and warm vintage (7–11 d). SST significantly increased the concentration of myricetin-based flavonols in wines which were 18% higher than in untreated wines. Through orthogonal partial least squares discriminant analysis (OPLS-DA), SST wines were characterized by more abundant phenolic compounds and higher sensory scores. The carry-over effect of applying SST in consecutive years in the same vines could be reflected in wine color. The correlations among wine metabolites, color and aroma parameters, and sensory parameters were evaluated through multiple analyses. This study provided an idea for delaying grape ripening in a semi-arid climate.

Effect of germination on the quality characteristics and volatile compounds of fermented brown rice cake

The objective of this study was to investigate the effect of different germination times (0–48 h) on the quality characteristics, especially the volatile compounds, of fermented brown rice cake (FBRC). Post-germination treatment, the viscoelasticity of the rice pulp decreased, also the hardness of FBRC steadily decreased. The 24 h germination time FBRC is considered to have the best quality including the smallest pore average area on the sliced surface and highest sensory score. In addition, the germination treatment also positively impacted the flavor of FBRC. Compared with the non-germination, the germinated groups had higher contents of alcohols, ketones, and heterocyclic compounds. The flavor volatile compounds could be generated via the amino acid metabolism and lipid oxidation pathways. A close correlation was found between the free amino acids, the free fatty acids and the main flavor volatile compounds. Principal component analysis indicated that the germination treatment improved the yeast flavor of brown rice cake; a short germination time was found best to provide a richer flavor. Overall, this study proved that moderate germination treatment effectively could improve the whole quality of FBRC.

Development of white finger millet probiotic beverage using Lactocaseibacillus rhamnosus (LGG): Process optimization and study of physicochemical and nutritional properties

AbstractWhite finger millet (WFM) is a repository of vital nutrients and minerals. This study aims to develop the white finger probiotic beverage, optimize the ingredients level for the formulation, and study the physiochemical and nutritional properties of the formulated vegan WFM probiotic beverage (WFMPB). The optimum condition for the development of WFMPB was obtained by Box–Behnken design. The independent variable like WFM flour (10–14% w/v), microbial inoculum (1–5% v/v), and sugar (5–15% w/v), and their impact on the response variables like total solid content (TSS), pH, microbial count, and viscosity were studied for optimization. Increment in the amounts of WFM flour and inoculum levels had a significant impact on the microbial load and pH. However, sugar levels affected viscosity and TSS. The combination of 14% WFM, 1% microbial inoculum, and 5% sugar showed maximum desirability of 0.975, with the highest sensory score (8.34), TSS of 15.4 °Brix, pH of 4.33, the microbial load of 9.45 log (cfu/ml) and viscosity of 43.32 cP. WFMPB consists of 11.91% carbohydrates, 1.46% protein, 0.89% fat, and 0.632% crude fiber. The rheological studies showed that WFMPB is a shear‐thinning fluid (n ˂ 0.1). The study revealed that WFM is the better carrier matrix for the LGG growth and can be an alternative for the strict vegan and lactose‐intolerant consumers.

Slightly acidic electrolyzed water-slurry ice: shelf-life extension and quality maintenance of mackerel (Pneumatophorus japonicus) during chilled storage.

Different ice treatments were applied for the preservation of mackerel (Pneumatophorus japonicus). The quality changes of samples treated with flake ice (Control), slurry ice (SI) and slightly acidic electrolyzed water-slurry ice (SAEW-SI) in microbiological, physicochemical, protein characteristic, and sensory evaluation were investigated during chilled storage. SAEW-SI showed a significant advantage for the inhibition of microbial growth, which could extend the shelf-life for another 144 h at least, compared with Control group. SAEW-SI treatment also showed a strong inhibition for the increase in pH, total volatile basic nitrogen (TVB-N), K-value, histamine and metmyoglobin (MetMb) content. Results of texture profile analysis (TPA) and water holding capacity (WHC) indicated that SAEW-SI can obviously suppress the decrease of hardness value, and have a better protective effect on muscle structure compared to flake ice and SI (P < 0.05). During the whole experiment, the highest sensory scores and a* were obtained in the SAEW-SI group, which indicated that SAEW-SI treatment could maintain better sensory characteristics. According to the results of thiobarbituric acid reactive substances (TBARS) and fluorescence spectroscopy analysis, SAEW-SI treatment could effectively retard protein degradation and lipid oxidation compared with Control and SI group. In maintaining the quality of mackerel, SAEW-SI shows a better effect than SI due to the synergistic effect of fence factors. The results demonstrated that the shelf-life of mackerel could be extended and the quality of mackerel could be maintained effectively with SAEW-SI treatment during chilled storage. © 2022 Society of Chemical Industry.

Effects of lactic acid bacteria fermentation on chemical compounds, antioxidant capacities and hypoglycemic properties of pumpkin juice

The purpose of this research was to screen strains to ferment pumpkin juice with excellent flavor and biological activities by the comparison of 5 species of lactic acid bacteria (LAB) strains, namely Lacticaseibacillus casei (Lc), Lactiplantibacillus plantarum (Lp), Lactobacillus acidophilus (La), Lactobacillus helveticus (Lh) and Lacticaseibacillus paracasei (Lpc). The pumpkin juice inoculated with LAB was fermented at 37 °C for 48 h. Viable cell counts were all above 7.92 log CFU/mL, implicating that pumpkin juice was a favorable matrix for LAB. The contents of reducing sugars and total sugars contents obviously declined at the end of fermentation. LAB strains utilized mainly fructose, surcose and glucose for fermentation. Lpc fermented pumpkin juice showed the most abundant organic acid. Furthermore, the strongest DPPH and hydroxyl radical scavenging capacities were observed in Lp, La and Lh, which were positively associated with vanillic acid and sinapic acid contents. There were 30 new volatile compounds that appeared after fermentation, including 8 of ketones and alcohols, 5 esters and so on. The highest sensory scores could be found in La and Lh primarily due to their rich volatile compounds. LAB fermentation was beneficial to inhibiting α-glucosidase and α-amylase activities. In conclusion, La and Lh were more suitable to develop into a functional beverage with pleasant flavor.