Quality Evaluation of Mackerel Fillets Stored under Different Conditions by Hyperspectral Imaging Analysis

This study was designed to compare the quality changes in mackerel fillets stored under different conditions by using hyperspectral imaging (HSI) techniques. Fillets packaged in vacuum were stored for six days under five different conditions: refrigerated at 4°C (R group); iced at 5±3°C (I group); kept at an ambient of 17±2°C (A group); frozen at -18°C for 24 h and thawed in a refrigerator at 4°C for 5 h on the sampling day (FTR group); FTR thawed in tap water instead of thawing in a refrigerator (FTW group). The FTR group had the lowest total bacterial count, drip loss, 2-thiobarbituric acid reactive substances, volatile basic nitrogen, and texture profile analysis values among groups during the entire storage period (p<0.05). Scanning electron microscopy revealed that the FTR group had less damage, while the other groups had shrunken muscle tissues. HSI integrated with the partial least squares model yielded reliable and efficient results, with high R2cv values, for several quality parameters of the mackerel fillets. Overall, the FTR group, involving freezing and thawing in a refrigerator, appears to be the most favorable option for maintaining the quality of mackerel fillets, which could be practically implemented in the industry. HSI is a suitable and effective technique for determining the quality of mackerel fillets stored under different conditions.

Selection of frozen-thawed stallion semen by microfluidic technology

The use of microfluidic technology is increasing in artificial reproduction technologies: With a small amount of semen, it allows for the selection of sperm with the best characteristics of kinetics, morphology and chromatin integrity. The ZyMot Multi (850 μl) is the most popular device of ZyMot Fertility Inc. To date, it was proven to be a valid instrument for sperm selection for in vitro fertilization and intracytoplasmic sperm injection in men. The aim of this study was to test the efficacy of the ZyMot Multi (850 μl) for stallion semen. Frozen-thawed semen from 15 stallions that were previously classified as being of 'good fertility' (GF; n = 8; pregnancy rate ≥ 40%) and 'poor fertility' (PF; n = 7; pregnancy rate < 20%), respectively, was used. Each ejaculate was assessed before and after microfluid recovery for kinetics (CASA), membrane integrity (MI) (SYBR14/PI), membrane functionality (MF) (HOS test), acrosome integrity (Spermac Stain Kit), morphology (Spermac stain kit), mitochondrial membrane potential (MMP) (JC-1) and chromatin integrity (aniline blue staining). Sperm concentration was reduced after sperm recovery in both groups, but more markedly in frozen-thawed semen of PF stallions (p < .05). Microfluid recovery increased total motility, MI, MF and MMP. While there was a significant increase in the percentage of progressively motile sperm after sperm microfluid recovery, there was a decrease in DAP, DSL, VAP, VSL, LIN, WOB and ALH (p < .05). A slight increase (p < .05) was detected in beat-cross frequency. The present results suggest that the ZyMot Multi (850 μl) device selects a specific sperm population from any stallion ejaculate with motile sperm and could therefore be a valid tool for in vitro testing with the aim to predict the fertility of frozen-thawed stallion semen.

Physicochemical Characteristics and Flavor-Related Compounds of Fresh and Frozen-Thawed Thigh Meats from Chickens

The physicochemical characteristics and flavor-related compounds of thigh meat derived from diverse Korean native chickens (KNC), namely Hanhyup No. 3 (HH3), Woorimatdag No 1 (WRMD 1), and Woorimatdag No 2 (WRMD 2), under fresh and frozen-thawed conditions were studied and compared with those of commercial broilers (CB). Regardless of the breed, KNC showed a higher (p < 0.05) percentage of linoleic and arachidonic acid. The highest proportion of docosahexaenoic acid was observed in WRMD 2. Despite having a higher collagen content, thigh meat derived from KNC maintained a similar texture profile in comparison to that of CB. The concentrations of most free amino acids (FAA), except for taurine, tryptophan, and carnosine, were higher in frozen-thawed meat than in fresh meat. Regarding volatile organic compounds (VOC), following freezing, the concentration of favorable VOCs increased in CB, but decreased in WRMD 1, suggesting a loss of pleasant flavor in frozen-thawed meat. This study indicated that changes in VOCs, including hydrocarbons (d-limonene, heptadecane, hexadecane, naphthalene, pentadecane, 3-methyl-, tridecane), esters (arsenous acid, tris(trimethylsilyl) ester, decanoic acid, ethyl ester, hexadecanoic acid, ethyl ester), alcohol (1-hexanol, 2-ethyl-), ketones (5,9-undecadien-2-one, 6,10-dimethyl-), and aldehydes (pentadecanal-, tetradecanal, tridecanal), may be a promising marker for distinguishing between fresh and frozen-thawed chicken thigh meat. These findings are of critical importance as preliminary data for developing high-quality chicken meat products.

Detection of previously frozen poultry through plastic lidding film using portable visible spectral imaging (443-726 NM)

The objective of this study is to use a portable visible spectral imaging system (443–726 nm) to detect poultry thawed from frozen at the pixel level using multivariate analysis methods commonly used in machine learning (decision tree, logistic regression, linear discriminant analysis [LDA], k-nearest neighbors [KNN], support vector machines [SVM]). The selection of the most suitable method is based on the amount of data required to build an accurate model, computational speed, and the robustness of the model. The training set consists of pixel spectra from packages of chicken thighs without plastic lidding to evaluate the robustness of the models when implemented on the test set with and without plastic lidding. Data subsets were created by randomly selecting 1, 5, 10, 20, and 50% of the pixel spectra of each sample for both the training and test data sets. The subsets of pixel spectra and the full training set were used to train the machine learning algorithms to evaluate how the amount of data influences computational time. Logistic regression was found to be the best algorithm for detecting poultry thawed from frozen with and without plastic lidding film. Although logistic regression and SVM both performed with the same high accuracy and sensitivity for all training subset sizes, the computational time needed to implement SVM makes it the less suitable algorithm for detecting poultry thawed from frozen with and without plastic lidding film.

Gallic acid improves the viability and mitochondrial membrane potential of post-thawed goat buck semen

The aim of this study was to determine the effects of gallic acid (GA) on frozen-thawed goat spermatozoa. Four Honamli goat bucks were used at their breeding season, and ejaculates were collected by an electroejaculator. Mixed semen was divided into the following four groups: control (0 mM), low (L; 1 mM), medium (M; 2 mM), and high (H; 4 mM) concentration of GA. All the groups were frozen and thawed in a water bath for spermatological evaluation. The lowest motility was observed in the control group (47.60 ± 5.70%) (P < 0.05), while the highest viability (62.45 ± 1.68%), plasma membrane and acrosome integrity (44.81 ± 4.57%), and high mitochondrial membrane potential (35.96 ± 2.50%) were observed in the low GA group (P < 0.05). Also, the lowest hypo-osmotic swelling test (HOS +) value was found in the high GA group (47.60 ± 4.82%) (P < 0.05). In conclusion, supplementing a low concentration (1 mM) of GA to the Tris-based semen extender had a positive effect on spermatological parameters after freeze-thawing of Honamli goat semen. Further studies should be continued in other species with different doses and combinations using commercial and/or homemade semen extenders.

Screening of frozen-thawed conditions for keeping nutritive compositions and physicochemical characteristics of goat milk

Frozen milk can help producers overcome the seasonality of goat milk production, low goat production and short lactation periods, and avoid discarding milk during some special periods. We investigated effects of combination between freezing (cryogenic refrigerator of -16 to -20°C or ultra-cryogenic refrigerator of -76 to -80°C) and thawing (homeothermy of 20 to 25°C or refrigeration of 2 to 4°C) on nutritive compositions and physicochemical characteristics of raw goat milk during storage period (80 d). Compared with fresh goat milk, the frozen-thawed milk decreased contents of fat, protein, and lactose, as well as surface tension and stability coefficient, whereas increased effective diameter and polydispersity index. The average values of color values (L*, a*, and b*) in 4 group samples changed from 83.01 to 82.25, -1.40 to -1.54, 3.51 to 3.81, respectively, and the ΔE of most samples did not exceed 2. In contrast to the other 3 frozen-thawed treatments, goat milk treated with ultra-cryogenic freezing-homeothermic thawing (UFHT) possessed higher fat (5.20 g/100 g), smaller effective particle diameter (0.32 µm), and the lowest polydispersity index value (0.26). The color and confocal laser scanning microscopy images of UFHT were similar to those of fresh goat milk, illustrating UFHT was the optimal approach to maintain the natural quality of goat milk. Our finding provides a theoretical basis for producers to freeze surplus milk.

Testicular sperm retrieval: What should we expect from the fresh and subsequent cryopreserved sperm injection?

We sought to compare ICSI outcomes of cycle using fresh versus thawed TESE spermatozoa obtained during the previous fresh TESE. All consecutive couples undergoing ICSI cycles using fresh TESE spermatozoa, followed by ICSI cycle using cryopreserved sperm remaining from the previous fresh TESE procedure were included. Ovarian stimulation (OS)/laboratory variables and cycle outcome were assessed and compared between those utilising fresh versus thawed TESE spermatozoa. Seventy-five couples were evaluated, with no in-between groups differences in OS nor embryological variables. While implantation and LBR per embryo transfer were nonsignificantly higher in the frozen as compared to the fresh TESE, there was a trend towards higher LBRs per patient in the frozen TESE group. The cumulative miscarriage rate (4% versus 14.7%, p < .022 respectively) was significantly lower and the cumulative LBR (34.7% versus 16%, p < .007 respectively) was significantly higher using frozen TESE spermatozoa. Moreover, significantly higher proportion of frozen TESE sperm samples used pentoxifylline to enhance sperm motility. In conclusion, the results of ICSI cycles using frozen TESE spermatozoa are as good, or even better than using fresh TESE spermatozoa. Further studies are required to explore the factors responsible for the improved ICSI outcome, while using frozen versus fresh TESE sperm samples.

Spermatozoa retrieved by electroejaculation: Should we prefer fresh or cryopreserved spermatozoa for intracytoplasmic sperm injection?

We aim to evaluate our experience, comparing intracytoplasmic sperm injection (ICSI) outcomes of cycle using fresh versus thawed electroejaculated spermatozoa. All consecutive couples undergoing ICSI cycles using electroejaculated spermatozoa, during a 16-year period, were evaluated. Embryological/laboratory variables of the ICSI cycles were assessed and compared between those utilising fresh (fresh group) versus thawed (thawed group) electroejaculated spermatozoa. Fifty-seven couples were evaluated, 30 used a fresh electroejaculated spermatozoa in 55 ICSI cycles, while 27 used a thawed sperm sample in 41 ICSI cycles. There were no in-between group differences in the mean numbers of oocytes retrieved per oocyte retrieval nor the percentage of MII oocytes. The fresh group demonstrated significantly higher fertilisation (71.5% vs. 64.1%, respectively, p < .05), top-quality embryos (66.5% vs. 54.9%, respectively, p < .02), clinical pregnancy per transfer (41.3% and 21.2%, respectively, p < .05) and cumulative clinical pregnancy (58.2% vs. 26.8%, respectively, p < .001) rates, as compared to the thawed group. Independent of the source of spermatozoa used, no pregnancy was achieved following ICSI utilising immotile spermatozoa. In conclusion, ICSI cycles using ejaculated spermatozoa of patients suffering from neurologic or psychogenic anejaculation are reassuring. The use of fresh ejaculated spermatozoa retrieved on the day of the female spouse oocyte retrieval might improve outcome. Whenever a thawed electroejaculated spermatozoa yield no motile spermatozoa, emergency electroejaculation is mandatory.

Ribose-induced Maillard Reaction as an Analytical Method for Detection of Adulteration and Differentiation of Chilled and Frozen-thawed Minced Veal

Quality control of meat products is one of the main concerns of consumers, governmental control authorities, and retailers. The purpose of this study was to employ ribose-induced Maillard reaction in detection of meat adulteration and differentiation of fresh-chilled from frozen-thawed minced veal. The browning intensity was assessed through measuring the absorbance at 420 nm with a spectrophotometer as well as the direct analysis of the color and pH. The results showed that CIE b*, CIE a*, and A_420* values in the extract of fresh-chilled veal were significantly (p<0.05) higher than frozen-thawed samples. The extract of frozen meat samples stored at −18°C became significantly darker and more yellowish compared to −4°C. The results showed that the A_420* value in the frozen-thawed veal stored at −4°C and −18°C was reduced by approximately 17.22±3.53% and 11.68±2.49%, respectively, compared with fresh-chilled veal. The findings also showed that the storage temperature of minced veal and the heating time in this reaction had a significant effect on all tested variables (p<0.0001). The proposed method can be considered as an easy, quick, and inexpensive test for differentiating between the fresh-chilled and frozen-thawed minced veal.

Treatment of thin endometrium with autologous platelet-rich plasma: a pilot study

Endometrium is one of the main factors in pregnancy. During assisted reproductive technology (ART) treatments, some cycles are cancelled due to inadequate endometrial growth. This study was conducted to evaluate the effectiveness of platelet-rich plasma (PRP) in the treatment of thin endometrium. Ten patients with history of inadequate endometrial growth in frozen-thawed embryo transfer (FET) cycles were recruited into the study. Intrauterine infusion of PRP was performed. Endometrial thickness was assessed. Chemical and clinical pregnancies were reported. In all patients, endometrial thickness increased after PRP and embryo transfer was done in all of them. Five patients were pregnant. According to this study, it seems that PRP was effective for endometrial growth in patient with thin endometrium.

Differentiation of Deboned Fresh Chicken Thigh Meat from the Frozen-Thawed One Processed with Different Deboning Conditions

This study was performed to evaluate the quality characteristics of three deboned categories of chicken thigh meat: one which was slaughtered and deboned in the same plant (fresh); one which was slaughtered, deboned, frozen, and thawed in the same plant (frozen-thawed); and the last which was slaughtered in a plant, deboned in a different plant, but then transferred to the original plant (fresh-outside). Surface color, drip loss, 2-thiobarbituric acid reactive substances (TBARS) value, sensory evaluation, and total aerobic bacterial counts of the chicken samples were determined. Moreover, the torrymeter was used to measure the differences in freshness of the chicken meat. The surface color and the TBARS values did not show significant differences among the three categories. However, the total aerobic bacterial counts of fresh-outside and frozen-thawed chicken meat were significantly higher than the fresh chicken meat on the first storage day, and the drip loss of frozen-thawed chicken meat was significantly higher than the fresh-outside and fresh chicken meat. In addition, the sensory evaluation of frozen-thawed chicken meat was significantly lower than the fresh-outside and fresh chicken meat. Torrymeter values were higher in fresh chicken meat than fresh-outside and frozen-thawed chicken meat during the storage period. These results indicate that the quality of frozen-thawed chicken meat is comparatively lower than the fresh chicken meat, and the torrymeter values can accurately differentiate the fresh-outside and frozen-thawed chicken meat from the fresh ones.