Effects of smoking and sun-drying on proximate, fatty and amino acids compositions of Southern pink shrimp (Penaeus notialis)

Metagenomic and metabolomic profiling of dried shrimp (Litopenaeus vannamei) prepared by a procedure traditional to the south China coastal area

Sun-drying is a traditional process for preparing dried shrimp in coastal area of South China, but its impacts on nutrition and the formation of flavor-contributory substances in dried shrimp remain largely unknown. This study aimed to examine the effects of the production process on the microbiota and metabolites in dried shrimp. 16S rDNA amplicon sequencing was employed to identify 170 operational taxonomic units (OTUs), with Vibrio, Photobacterium, and Shewanella emerging as the primary pathogenic bacteria in shrimp samples. Lactococcus lactis was identified as the principal potential beneficial microorganism to accrue during the dried shrimp production process and found to contribute significantly to the development of desirable shrimp flavors. LC-MS-based analyses of dried shrimp sample metabolomes revealed a notable increase in compounds associated with unsaturated fatty acid biosynthesis, arachidonic acid metabolism, amino acid biosynthesis, and flavonoid and flavanol biosynthesis throughout the drying process. Subsequent exploration of the relationship between metabolites and bacterial communities highlighted the predominant coexistence of Bifidobacterium, Clostridium, and Photobacterium contributing heterocyclic compounds and metabolites of organic acids and their derivatives. Conversely, Arthrobacter and Staphylococcus were found to inhibit each other, primarily in the presence of heterocyclic compounds. This comprehensive investigation provides valuable insights into the dynamic changes in the microbiota and metabolites of dried shrimps spanning different drying periods, which we expect to contribute to enhancing production techniques and safety measures for dried shrimp processing.

Nutritional Quality and Fatty Acids Composition of Invasive Chinese Mitten Crab from Odra Estuary (Baltic Basin)

The Chinese mitten crab (Eriocheir sinensis) is recognized as an invasive species in Europe but increasing fishing efforts may hold economic benefits and yield positive ecological and nutritional outcomes. The objective of this study was to determine the yield of edible parts and the compositional and nutritional characteristics of this crab, especially as a source of n-3 PUFA. The overall yield of edible parts amounted to 38.09%, with males (27.72%) exhibiting a higher meat content compared to females (25.30%). The gonads displayed the highest protein content (24.12%), while the hepatopancreas (11.67%) showcased the highest fat content. Furthermore, the fatty acid composition varied depending on the distribution within different crab segments and gender and individual size. Notably, the gonad lipids contained the most nutritionally valuable n-3 fatty acids, followed by muscle and hepatopancreas lipids. The determined index of atherogenicity (IA) from 0.2 for gonadal lipids to 0.42 for hepatopancreas lipids, index of thrombogenicity (IT) in the range of 0.10 for gonads to 0.41 for hepatopancreas, and flesh lipid quality (FLQ) from 6.9 for hepatopancreas to 23 for muscle lipids indicate their pro-health properties. The ratio of n-3 to n-6 fatty acids showed Chinese mitten crab as an excellent source of oil that can be used for food fortification and dietary supplement production.

Enhancing the Nutritional Profile of Tenebrio molitor Using the Leaves of Moringa oleifera

Nowadays, more and more research is being carried out on various feeds of Tenebrio molitor larvae, in order to increase their nutritional value and render them a valuable component of the human diet. In this study, Moringa oleifera leaves were used in different proportions (up to 50%) to substitute wheat bran (the usually employed feed), in order to evaluate their effect on the growth and development of the larvae, as well as on their composition in crude protein, fat and fatty acids, ash, vitamins, and antioxidants. It was found that the addition of M. oleifera leaves in the feed had no negative impact on the development and survival of the insects, while an increase in their nutritional value was recorded. More specifically, an increase in the crude protein of up to 22.61% and vitamin C and A contents of up to 40.74% and 491.63%, respectively, was recorded. Therefore, the use of M. oleifera leaves as a feed additive is highly recommended for rearing T. molitor larvae to enhance the nutritional value of the insects.

Effect of lipid oxidation on quality attributes and control technologies in dried aquatic animal products: a critical review

Aquatic animals are viewed as a good source of healthy lipids. Although drying is an effective method for the preservation of aquatic animal products (AAPs), the whole process is accompanied by lipid oxidation. This article reviews the main mechanism of lipid oxidation in the drying process. It also summarizes the effects of lipid oxidation on the quality of dried aquatic animal products (DAAPs), including nutrients, color, flavor, and hazard components, especially for those harmful aldehydes and heterocyclic amines. In addition, it concluded that moderate lipid oxidation contributes to improving the quality of products. Still, excessive lipid oxidation produces hazardous substances and induces health risks. Hence, to obtain high-quality DAAPs, some effective control technologies to promote/prevent lipid oxidation are introduced and deeply discussed, including salting, high-pressure processing, irradiation, non-thermal plasma technology, defatting treatments, antioxidants, and edible coating. A systematic review of the effect of lipid oxidation on quality attributes and control technologies in DAAPs is presented, and some perspectives are made for future research.

Safety and quality assessment of street-vended barbecue chicken samples from Faisalabad, Pakistan

The current study was designed to assess the safety and quality status of street-vended barbecue chicken samples. The samples were collected from four regions of Faisalabad city: Ghulam Mohammad Abad (R1), Jhang Road (R2), Sargodha Road (R3), and Satiana Road (R4); and compared with the self-prepared barbecue chicken sample (R0). Purposely, all the collected samples were subjected to assess the quality aspects by physicochemical analyses. The results of the physicochemical analysis showed that moisture content varied from 54% to 60%, crude protein 26.97% to 32.87%, crude fat 7.25% to 9.00%, crude ash 1.61% to 1.72%, pH 5.60 to 6.30, free fatty acid value 1.00% to 1.39%, and peroxide value 0.63 to 0.84 meq/Kg. Results pertaining to the enumeration of total microbial load and total coliform count exhibit 2.39-5.17 and 1.20-3.20 log cfu/g, respectively. The samples were assessed for heavy metals (Pb, Zn, Cd, and Fe) by atomic absorption spectrophotometer (AAS). The concentration of highly toxic metals Pb and Cd was found to be much higher than recommended value as they ranged from 1.90 to 3.70 mg/kg for Pb and 0.10 to 0.90 mg/kg for Cd. However, the level of essential metals (Fe and Zn) in barbecue chicken samples ranged from 67.10 to 180 and 8.30 to 35.80 mg/kg which was much higher than their safe limits for Fe (15 ppm) and Zn (5 ppm), respectively. The study concludes that the consumption of street-vended barbecue chicken possesses to be a serious public health risk for consumers.

Effects of Repeated Heating on Fatty Acid Composition of Plant-Based Cooking Oils

Several polyunsaturated fatty acids are considered to have beneficial health effects, while saturated fatty acids and industrial trans fatty acids (TFAs) are linked to negative health consequences. Given the increased formation of TFAs during heating, many studies already investigated compositional changes in oils after prolonged heating or at extremely high temperatures. In contrast, our aim was to measure changes in fatty acid composition and in some health-related indices in edible oils after short-time heating that resembles the conventional household use. Potatoes were fried in palm, rapeseed, soybean, sunflower and extra virgin olive oils at 180 °C for 5 min, and samples were collected from fresh oils and after 1, 5 and 10 consecutive heating sequences. Regardless of the type of oil, the highest linoleic acid and alpha-linolenic acid values were measured in the fresh samples, whereas significantly lower values were detected in almost all samples following the heating sequences. In contrast, the lowest levels of TFAs were detected in the fresh oils, while their values significantly increased in almost all samples during heating. Indices of atherogenicity and thrombogenicity were also significantly higher in these oils after heating. The present data indicate that prolonged or repeated heating of vegetable oils should be avoided; however, the type of oil has a greater effect on the changes of health-related indices than the number of heating sequences.

Determination of microbial diversities and aroma characteristics of Beitang shrimp paste

Beitang shrimp paste (BSP) is fermented by different parts of shrimp, such as the head (H), meat (M), or the whole shrimp (S and W). Microbial communities of BSP were dominated by Firmicutes and Proteobacteria at the phyla level and Tetragenococcus at the genus level. However, the microbial diversity of M was the lowest than the others. Non-dominant bacterial communities were presented by a mutual symbiotic model in BSP fermentation. Tetragenococcus, Halanaerobium, Streptococcus, and Brevundimonas were positively correlated with the biosynthesis of amino acids, fatty acids, and metabolic cofactors; Marinilactibacillus and Pseudomonas might be the main contributors to inorganic sulfides, nitrogen oxides, and long-chain alkanes in BSP; Psychrobacter was closely related to the ester characteristics of methyl palmitoleate and methyl hexadecanoate in H. Halanaerobium and Streptococcus promoted the production of pyrazines in S. Tetragenococcus was positively correlated with acetic acid, decanoic acid, and palmitic acid that improved the sour aroma of M. The relationship between bacteria and aroma formation under different raw materials was expected to improve the quality of BSP.

Nutritional Indices for Assessing Fatty Acids: A Mini-Review

Dietary fats are generally fatty acids that may play positive or negative roles in the prevention and treatment of diseases. In nature, fatty acids occur in the form of mixtures of saturated fatty acid (SFA), monounsaturated fatty acid (MUFA), and polyunsaturated fatty acid (PUFA), so their nutritional and/or medicinal values must be determined. Herein, we do not consider the classic indices, such as ∑SFA, ∑MUFA, ∑PUFA, ∑n-6 PUFA, ∑n-3 PUFA, and n-6 PUFA/n-3 PUFA; instead, we summarize and review the definitions, implications, and applications of indices used in recent years, including the PUFA/SFA, index of atherogenicity (IA), the index of thrombogenicity (IT), the hypocholesterolemic/hypercholesterolemic ratio (HH), the health-promoting index (HPI), the unsaturation index (UI), the sum of eicosapentaenoic acid and docosahexaenoic acid (EPA + DHA), fish lipid quality/flesh lipid quality (FLQ), the linoleic acid/α-linolenic acid (LA/ALA) ratio, and trans fatty acid (TFA). Of these nutritional indices, IA and IT are the most commonly used to assess the composition of fatty acids as they outline significant implications and provide clear evidence. EPA + DHA is commonly used to assess the nutritional quality of marine animal products. All indices have their advantages and disadvantages; hence, a rational choice of which to use is critical.

Proximate analysis and fatty acid of Corbicula fluminea (C. fluminea) tissue in Kelantan, Malaysia

Corbicula fluminea (C. fluminea) is one of the mollusc species commonly eaten as a popular snack in Kelantan, Malaysia. This species contributes to the local economic activity. However, the handling process of C. fluminea at different processing stages (raw, smoke and selling stages) is believed to have affected the nutritional value in their soft tissue. Hence, this study aims to provide information about the chemical content (moisture, crude fat, ash, crude protein and carbohydrate) of C. fluminea and fatty acid of smoked C. fluminea at different processing stages. Samples were collected from Pasir Mas and Tumpat, Kelantan, Malaysia. The chemical content analysis was carried out based on the Association of Official Analytical Chemists (AOAC) standard procedures. The results have indicated that moisture (80.93 ± 0.37%) and crude fat (10.82 ± 0.21%) in C. fluminea were significantly higher (p < 0.05) at the raw stage. On the other hand, the ash (2.09 ± 0.03%) and crude protein (9.45 ± 0.42%) were significantly higher (p < 0.05) at smoked stage. Meanwhile, carbohydrate (3.39 ± 0.49%) was significantly higher (p < 0.05) at the selling stage. The fatty acid percentage of smoked C. fluminea indicates that the total saturated fatty acid (SFA) content was higher than the total of both monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA). The obtained data indicates that the composition percentage of omega-6 (n-6) in PUFA is significantly greater than omega-3 (n-3). The n-6/n-3 ratio of smoked C. fluminea is 2.95-3.11 and therefore can be considered as a healthy diet. The findings of this study can improve consumers' health through sufficient nutrient consumption and also provide economic benefits by increasing sellers' income in Kelantan.

Domestic Cooking of Muscle Foods: Impact on Composition of Nutrients and Contaminants

Meat and fish are muscle foods rich in valuable nutrients, such as high-quality proteins, vitamins, and minerals, and, in the case of fish, also unsaturated fatty acids. The escalation of meat and fish production has increased the occurrence of pesticide and antibiotic residues, as result of pest control on feed crops, and antibiotics used to fight infections in animals. Meat and fish are usually cooked to enrich taste, soften texture, increase safety, and improve nutrient digestibility. However, the impact of cooking on nutritional properties and formation of deleterious compounds must be understood. This review summarizes studies, published in the last decade, that have focused on how domestic cooking affects: (i) composition of nutrients (protein, fatty acids, vitamins, and minerals); (ii) antibiotic and pesticide residue contents; and (iii) the formation of cooking-induced contaminants (heterocyclic aromatic amines, polycyclic aromatic hydrocarbons, and thermal degradation products of antibiotics and pesticides). Cooking affects the nutritional composition of meat and fish; frying is the cooking method that causes the greatest impact. Cooking may reduce the pesticide and antibiotic residues present in contaminated raw meat and fish; however, it may result in the formation of degradation products of unknown identity and toxicity. Control of cooking time and temperature, use of antioxidant-rich marinades, and avoiding the dripping of fat during charcoal grilling can reduce the formation of cooking-induced contaminants.

Microbiological and chemical changes of shrimp Acetes vulgaris during Kapi production

Microbiological and chemical changes in shrimp Acetes vulgaris during production of Kapi (salted shrimp paste of Thailand) including salting, drying and fermentation were monitored. Moisture content of samples decreased rapidly after salting and drying steps. The lower water activity was found in the final product (0.694). The pH decreased within the first 10 days of fermentation and continuously increased as fermentation progressed. Protein underwent degradation throughout Kapi production as indicated by increasing TCA-soluble peptides and degree of hydrolysis. The increases in peroxide value as well as thiobarbituric acid reactive substances value revealed that lipid oxidation occurred throughout all processes. Total viable count, halophilic, proteolytic and lipolytic bacteria counts increased continuously during Kapi production, while lactic acid bacteria count slightly decreased at the final stage of fermentation. Thus, proteolysis and lipolysis took place throughout Kapi production, and contributed to the characteristics of finished product. These changes were governed by both endogenous and microbial enzymes.