Correlations between the levels of the bioactive compounds and quality traits in beef loin and round during cold storage

Acoustic Characterization Study of Beef Loins Using Ultrasonic Transducers

The objective of this study was to non-destructively characterize samples of fresh beef loin by low-intensity ultrasound inspection at various frequencies and to correlate the acoustic parameters of these inspections with quality parameters. In this regard, ultrasonic parameters such as ultrasound pulse velocity (UPV) and variables related to attenuation and frequency components obtained from fast Fourier transform (FFT) were considered. For this, pulsed ultrasonic signal transducers with a frequency of 0.5 and 1.0 MHz were used. Acoustic parameters and those obtained through traditional instrumental analyses (physicochemical and texture) underwent a Pearson correlation analysis. The acoustic determinations revealed numerous significant correlations with the rest of the studied parameters. The results demonstrate that ultrasonic inspection has the ability to characterize samples with a non-destructive nature, and likewise, this methodology can be postulated as a promising predictive tool for determining quality parameters in beef loin samples.

Dandelion (Taraxacum mongolicum) Extract Alleviated H2O2-Induced Oxidative Damage: The Underlying Mechanism Revealed by Metabolomics and Lipidomics

Dandelion has received wide attention in food and medicine fields due to its excellent antioxidant properties. Nonetheless, the underlying mechanism of this action has not yet been fully clarified, particularly at the metabolic level. Herein, the effects of dandelion extract (DE) on H2O2-induced oxidative damage was investigated. The results indicate that the DE alleviated H2O2-induced cell damage (increased by 14.5% compared to H2O2 group), reduced the reactive oxygen species (ROS) level (decreased by 80.1% compared to H2O2 group), maintained the mitochondrial membrane potential (MMP) level, and increased antioxidant-related enzyme activities. Importantly, the metabolic response of PC12 cells indicates that H2O2 disturbed phospholipid metabolism and damaged cell membrane integrity. In addition, energy metabolism, the central nervous system, and the antioxidant-related metabolism pathway were perturbed. In contrast, DE rescued the H2O2-induced metabolic disorder and further alleviated oxidative damage. Collectively, these findings provide valuable stepping stones for a discussion of the mechanism and show the promise of DE as a suitable additive for functional food products.

Physicochemical Properties and Volatile Organic Compounds of Dairy Beef Round Subjected to Various Cooking Methods

To evaluate the effect of different cooking methods on the physicochemical quality and volatile organic compounds (VOC) of dairy beef round, twelve beef round pieces were divided into four groups: raw, boiling, microwave, and sous-vide. The sous-vide group had a higher pH than the boiling or microwave groups. The boiling group exhibited the highest shear force and CIE L*, followed by the microwave and sous-vide groups (p<0.05). The sous-vide group received higher taste and tenderness scores from panelists (p<0.05) and showed significantly higher levels of aspartic and glutamic acids than the other groups. The sous-vide and microwave groups had the highest oleic acid and polyunsaturated fatty acid levels, respectively. The sous-vide group had significantly higher hypoxanthine and inosine levels than the other groups. However, the microwave group had higher inosine monophosphate levels than the other groups. The sous-vide group had a higher alcohol content, including 1-octen-3-ol, than the other groups. Octanal and nonanal were the most abundant aldehydes in all groups. (R)-(-)-14-methyl-8-hexadecyn-1-ol, p-cresol, and 1-tridecyne were used to distinguish the VOC for each group in the multivariate analysis. Sous-vide could be effective in increasing meat tenderness as well as taste-related free amino acid (aspartic acid and glutamic acid) and fatty acid (oleic acid) levels. Furthermore, specific VOC, including 1-octen-3-ol, 2-ethylhexanal ethylene glycol acetal, and 2-octen-1-ol, (E)-, could be potential markers for distinguishing sous-vide from other cooking methods. Further studies are required to understand the mechanisms underlying the predominant association of these VOC with the sous-vide cooking method.

Effect of Feeding Alfalfa and Concentrate on Meat Quality and Bioactive Compounds in Korean Native Black Goat Loin during Storage at 4°C

The primary aim of this study was to evaluate the effect of feeding alfalfa: Concentrate at different ratios (8:2 or 2:8) to Korean native black goats (KNBG) for 90 days on meat quality and bioactive compound content. Feeding KNBG alfalfa and concentrate at different ratios did not impact meat pH, color, microorganism composition, volatile basic nitrogen levels, or lipid oxidation. The low alfalfa (KLA) group exhibited increased oleic acid and monosaturated fatty acid levels, both of which impact the palatability traits of meat. The abundance of bioactive compounds increased in the loin meat of the KLA group, leading to an increase in antioxidant activities. Our results suggest that feeding alfalfa and concentrate at a 2:8 ratio to KNBG can increase taste-related fatty acids and bioactive compounds in loin meat, relative to that achieved by feeding at an 8:2 ratio. Further investigation is required to evaluate the quality and the metabolites of bioactive compounds in KNBG meat and the effect of the different dietary ratios of forage and concentrate.

Effect of Marination with Black Currant Juice on the Formation of Biogenic Amines in Pork Belly during Refrigerated Storage

The effect of marination with black currant juice (BCJ) was investigated for their effects on meat quality and content of biogenic amines (BAs) [putrescine (PUT), cadaverine (CAD), histamine (HIM), tyramine (TYM), and spermidine (SPD)] in pork belly during storage at 9°C. BCJ was shown to have antibacterial activities against Escherichia coli and Pseudomonas aeruginosa. Additionally, the pH of pork belly marinated with BCJ (PBB) was significantly lower than that of raw pork belly (RPB) during storage. No significant difference in microorganisms between RPB and PBB was observed at day 0 of storage. However, at days 5 and 10 of storage, volatile basic nitrogen (VBN) was significantly decreased in PBB compared to RPB, and PBB also demonstrated significantly lower numbers of bacteria associated with spoilage (Enterobacteriaceae and Pseudomonas spp.) at these time-points. PBB was also associated with significantly reduced formation of BAs (PUT, CAD, TYM, and total BAs) compared to RPB at days 5 and 10 of storage. These results indicated that BCJ can be regarded as a natural additive for improving meat quality by preventing increased pH, VBN, bacterial spoilage, and inhibiting BAs formation during refrigerated storage.

Effects of Gochujang (Korean Red Pepper Paste) Marinade on Polycyclic Aromatic Hydrocarbon Formation in Charcoal-Grilled Pork Belly

Charcoal-grilling is a popular cooking method but causes the formation of polycyclic aromatic hydrocarbons (PAHs), which can be harmful to human health. Gochujang marinade is commonly used for flavoring meats during charcoal-grilling. However, the effects of this marinade on PAHs formation during charcoal-grilling are unclear. Here, we evaluated the effects of Gochujang marinade on the formation of 16 PAHs and inhibition rate of major PAHs (benzo[a]anthracene, benzo[b]fluoranthene, and benzo[a]pyrene) in charcoal-grilled pork belly. Pork belly without marinade (PBW) and marinated with Gochujang (PBG) were stored for 10 days at 9°C under vacuum conditions and then charcoal-grilled to different doneness (internal temperatures of 71°C and 81°C). Among 16 PAHs evaluated in this study, 14 PAHs were detected in charcoal-grilled pork belly, regardless of doneness. PAH formation in charcoal-grilled pork belly was higher at an internal temperature of 81°C than at 71°C (p<0.05). Initially, PBG showed reduced total PAH formation and lower percentages of three major PAHs compared with PBW. Storage increased the inhibitory effects of PBG on the 16 PAHs, and the maximum reduction in total 16 PAHs (63.06%) was observed with moderate cooking (71°C) on day 10 (p<0.05). Moreover, marinade and doneness showed a high interaction with regard to PAH contents in charcoal-grilled pork belly (p<0.05-p<0.0001). Therefore, our findings suggested that marinating pork belly with Gochujang and grilling at 71°C could reduce the formation of 16 PAHs in charcoal-grilled pork belly.

Utilization of Electrical Impedance Spectroscopy and Image Classification for Non-Invasive Early Assessment of Meat Freshness

This study presents a system for assessing the freshness of meat with electrical impedance spectroscopy (EIS) in the frequency range of 125 Hz to 128 kHz combined with an image classifier for non-destructive and low-cost applications. The freshness standard is established by measuring the aerobic plate count (APC), 2-thiobarbituric acid reactive substances (TBARS), and composition analysis (crude fat, crude protein, and moisture) values of the microbiological detection to represent the correlation between EIS and meat freshness. The EIS and images of meat are combined to predict the freshness with the Adaboost classification and gradient boosting regression algorithms. As a result, when the elapsed time of beef storage for 48 h is classified into three classes, the time prediction accuracy is up to 85% compared to prediction accuracy of 56.7% when only images are used without EIS information. Significantly, the relative standard deviation (RSD) of APC and TBARS value predictions with EIS and images datum achieves 0.890 and 0.678, respectively.