Search Results (10)

Stir-frying is an important process for terminating fermentation and improving the flavor of sour shrimp paste. This study investigated the flavor characteristics, volatile profiles, and post-storage microbial community of stir-fried sour shrimp paste. Sensory evaluation demonstrated that it exhibits a well-balanced flavor profile, characterized by fruity, soy sauce, spicy, and salty notes. Based on HS-SPME-GC-MS analysis, a total of 68 volatile compounds were identified, of which 26 made notable contributions to the aroma. Among them, esters were the most diverse group, with ethyl butyrate, ethyl acetate, and ethyl 2-methylbutyrate serving as the main contributors to the fruity aroma. Acids such as butanoic acid, acetic acid, and 2-methylbutanoic acid far exceeded their thresholds, linking to sour and spicy notes. Microbial community analysis revealed that low-abundance fermentative bacteria, such as Vagococcus and Levilactobacillus, remained detectable after storage, whereas Pseudomonas and Acinetobacter were identified as the most probable spoilage organisms. These findings provide a systematic understanding of the unique flavor of stir-fried sour shrimp paste and its potential microbial risks during storage, providing a basis for the application of stir-frying technology. Full article

Terasi, or fermented shrimp paste, is a staple condiment in Indonesian cuisine, produced through spontaneous fermentation of small crustaceans under high-salt conditions. Despite its widespread culinary use, comprehensive studies examining both the microbiota and volatile compounds in commercial terasi remain scarce. This study aimed to characterize the microbial composition and volatile profiles of ten commercial terasi products sourced from different regions of Indonesia, representing both traditional home industries and large-scale manufacturers. Culture-dependent microbial enumeration and 16S rRNA gene sequencing were employed to assess microbial diversity, while volatile compounds were identified and quantified using gas chromatography–mass spectrometry (GC-MS). Results revealed significant differences in microbial load and community composition among samples, with traditional products showing higher viable counts and microbial diversity, dominated by genera such as Tetragenococcus, Bacillus, Weissella, and Halanaerobium. Industrial samples, by contrast, contained no detectable microorganisms, likely due to sterilization practices for extended shelf life. A wide range of volatiles, including sulfur compounds, short-chain fatty acids, and trimethylamine, were identified across all samples, with a total of 48 detected compounds. Notably, correlation analysis revealed strong associations between specific bacterial genera and key volatile compounds, suggesting that microbial activity plays a central role in shaping terasi’s flavor. This integrative analysis provides new insights into the microbial–chemical interactions underlying fermented shrimp paste and offers potential applications for product standardization, starter culture development, and culinary innovation. Full article

The demand for sustainable protein has increased interest in edible insects, and fermentation can improve the sensory and nutritional profiles of novel foods. This study aimed to develop a fermented cricket paste using a method analogous to traditional shrimp paste and evaluate the physiochemical, nutritional, microbiological, and sensory properties. Both pastes were produced via a biphasic fermentation protocol and subsequently analyzed for their physicochemical, nutritional, microbiological, and sensory properties including consumer acceptance testing in a chili paste. The cricket paste showed a comparable protein content, but higher in carbohydrates and lower in fat. It also showed enhanced stability and safety, with a significantly lower level of histamine (2.37 ppm) compared with shrimp paste (50.51 ppm). While the microbial profiles were broadly similar, the cricket paste had a lower lactic acid bacteria community. Sensory analysis revealed distinct profiles, with the cricket paste characterized by a dark color, coarse texture, nutty/earthy aroma, bitter, and less umami. Despite these differences, consumer liking for chili pastes made with either product was statistically identical. Cricket paste is therefore a safe, stable, and nutritionally advantageous alternative that is highly acceptable to consumers when used as a culinary ingredient. Full article

The study aimed to identify potential sources of novel probiotic yeasts exhibiting health-promoting properties. A combination of metabarcoding analysis and cultural methods was employed to investigate and isolate yeasts from various sources, including rice wine, palm wine, fermented shrimp paste at different stages of natural fermentation, and lychee peels. The two analytical methods revealed distinct yeast profiles, and each source exhibited a unique composition of yeast species. Through metabarcoding and cultural methods, it was demonstrated that lychee peels harbored a greater diversity of genera compared to other sources. The evaluation of the probiotic properties of yeasts revealed that lychee peel yielded the highest proportion of isolates with potential probiotic activity (53.33%), followed by palm wine (25%), fermented shrimp paste (10%), and rice wine (9.09%). Moreover, yeast isolates with health-promoting properties as evaluated in this study, including Starmerella meliponinorum L12 and Pichia terricola L9 from lychee peels, demonstrated notable antioxidant activity and cholesterol-reducing properties, respectively. These findings represent the first report providing initial insights into the influence of yeast sources and serve as a guideline for the targeted selection of yeasts with specific probiotic and health-promoting attributes. Full article

This study was conducted to investigate the effect of inoculation with Exiguobacterium profundum FELA1 isolated from traditional shrimp paste and koji on the taste, flavor characteristics, and bacterial community of rapidly fermented shrimp paste. E-nose and e-tongue results showed higher levels of alcohols, aldehydes, and ketones, enhanced umami and richness, and reduced bitterness and astringency in samples of shrimp paste inoculated with fermentation (p < 0.05). Eighty-two volatile compounds were determined using headspace solid-phase microextraction and gas chromatography–mass spectrometry (HS-SPEM-GC-MS). The contents of 3-methyl-1-butanol, phenylethanol, isovaleraldehyde, and 2-nonanone in the inoculated samples were significantly increased (p < 0.05), resulting in pleasant odors such as almond, floral, and fruity. High-throughput sequencing results showed that the addition of koji and FELA1 changed the composition and abundance of bacteria and reduced the abundance of harmful bacteria. Spearman’s correlation coefficient indicated that the alcohols, aldehydes, and ketones of the inoculated fermented samples showed a strong correlation (|ρ| > 0.6) with Virgibacillus and Exiguobacterium, which contributed to the formation of good flavor in the fast fermented shrimp paste. This study may offer new insights into the production of rapidly fermented shrimp paste with better taste and flavor. Full article

Fermented shrimp paste is a popular food in Asian countries. However, biogenic amines (BAs) are a typically associated hazard commonly found during the fermentation of shrimp paste and pose a food-safety danger. In this work, an autochthonic salt-tolerant Tetragenococcus muriaticus TS (T. muriaticus TS) strain was used as a starter culture for grasshopper sub shrimp paste fermentation. It was found that with the starter culture, putrescine, cadaverine, and histamine concentrations were significantly lower (p < 0.05) with a maximal reduction of 19.20%, 14.01%, and 28.62%, respectively. According to high-throughput sequencing data, T. muriaticus TS could change the interactions between species and reduce the abundance of bacterial genera positively associated with BAs, therefore inhibiting the BA accumulation during shrimp paste fermentation. Moreover, the volatile compounds during the fermentation process were also assessed by HS-SPME-GC-MS. With the starter added, the content of pyrazines increased, while the off-odor amines decreased. The odor of the shrimp paste was successfully improved. These results indicate that T. muriaticus TS can be used as an appropriate starter culture for improving the safety and quality of grasshopper sub shrimp paste. Full article

This study aimed to evaluate Bacillus subtilis K-C3 as a potential starter to improve shrimp paste quality, particularly in terms of nutritional profiles. The quality/characteristic changes of shrimp paste with and without inoculation during storage for 18 months when stored at low (4 °C) and room (28 °C) temperature were also investigated. The results found that this B. strain increased essential amino acids (EAAs) and polyunsaturated fatty acids (PUFAs), as well as antioxidant properties including 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging activities, ferric reducing antioxidant power (FRAP) and metal chelating activity in the experimental shrimp paste compared to traditional shrimp paste (p < 0.05). The faster development of some characteristics of inoculated samples were also noted, as indicated by the higher total viable count (TVC), formal and amino nitrogen content, pH, and browning index, as well as biogenic amines, indicating different quality which may be further responsible for different product acceptability. The changes in quality/characteristics of shrimp paste were observed throughout the 18 months of storage. Shrimp paste stored at room temperature accelerated those changes faster than samples stored at low temperature (p < 0.05); however, the quality of them still meets the product’s standard even storage for 18 months. Meanwhile, shrimp paste stored at a low temperature had an amount of yeast and mold over the limitation (>3.00 log CFU/g), indicating food spoilage. Thus, storage at room temperature can extend this product’s shelf-life better than storage at low temperature. Overall, inoculation with B. subtilis K-C3, in conjunction with storage at room temperature, resulted in quality improvement and maintenance in shrimp paste, particularly in the aspects of nutritional profiles and safety concern, as the shrimp paste should have a shelf-life of at least 18 months. Full article

The present study focused on the determination of color, flavor, taste, and volatile organic compounds (VOCs) changes of shrimp paste fermented for 1, 2, 3, and 8 years by E-nose, E-tongue, and headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS). During fermentation, the color of shrimp paste turned dark brown with decreases in L*, a*, and b* values. Inorganic sulfide odor was dominant in all fermented samples. The umami, richness, and aftertaste-B reached a maximum in year 3 of fermentation. A total of 182 volatiles, including long-chain alkanes, esters, aldehydes, olefins, ketones, acids, furans, and pyrazines, were detected. Sixteen VOCs including dimethyl disulfide, methional, trimethyl-pyrazine, (E,E)-2,4-heptadienal, benzeneacetaldehyde were selected as flavor markers. Correlation analysis showed that 94 VOCs were related to saltiness while 40, 17, 21, 22, and 24 VOCs contributed to richness, umami, aftertase-B, sourness, and bitterness, respectively. These novel data may help in optimizing fermentation duration to achieve target flavor indicators in opossum shrimp paste production. Full article

Quality changes of salted shrimp paste, one of the most popular traditional Thai fermented food ingredients, stored in different packaging containers including polypropylene containers (PP), polyethylene terephthalate containers (PET), glass jar containers (GJ) as well as LLDPE/Nylon vacuum bags (VB) at room temperature (28 ± 1 °C) for 15 months were studied. The relationship between quality attributes (i.e., volatiles, browning index (A₄₂₀), biogenic amines, TBARS) and consumer acceptability as indicated by sensory scores were also investigated using principal component analysis (PCA). During storage, some desirable quality characteristics of shrimp paste were improved as indicated by the higher sensory scores of all samples when stored for 6 months, compared with the sample at day 0 (p ≤ 0.05). However, further changes in all compositions when extended storage time can conversely diminish those desirable characteristics and led to lowering consumers’ acceptability. In this study, GJ seem to be the most potential packaging for preserving original products’ quality during storage for this product since it exhibited the lower rate of quality changing than others throughout the storage. Conversely, VB exhibited unique volatiles and microbial profiles, compared with others, which led to the lowest sensory scores at all period test (p ≤ 0.05), implying that vacuum conditions may not be suitable for the storage of this product. Moreover, based on PCA results, the intensity of nitrogen-containing compounds correlated well with sensory acceptability, particularly flavor-likeness. Our study provides useful knowledge for understanding the different quality characteristics, particularly flavors, associated with different packaging containers during prolonged storage of salted shrimp paste. Full article

Low-salt shrimp paste, or terasi, is an Indonesian fermented food made from planktonic shrimp mixed with a low concentration of salt. Since high daily intake of sodium is deemed unhealthy, reduction of salt content in shrimp paste production is desired. Until now, there is no reported investigation on the bacterial population and metabolite composition of terasi during fermentation. In this study, the bacterial community of terasi was assessed using high-throughput sequencing of the 16S rRNA V3–V4 region. From this analysis, Tetragenococcus, Aloicoccus, Alkalibacillus, Atopostipes, and Alkalibacterium were found to be the dominant bacterial genus in low-salt shrimp paste. GC/MS-based metabolite profiling was also conducted to monitor the metabolite changes during shrimp paste fermentation. Results showed that acetylated amino acids increased, while glutamine levels decreased, during the fermentation of low-salt shrimp paste. At the start of shrimp paste fermentation, Tetragenococcus predominated with histamine and cadaverine accumulation. At the end of fermentation, there was an increase in 4-hydroxyphenyl acetic acid and indole-3-acetic acid levels, as well as the predominance of Atopostipes. Moreover, we found that aspartic acid increased during fermentation. Based on our findings, we recommend that fermentation of low-salt shrimp paste be done for 7 to 21 days, in order to produce shrimp paste that has high nutritional content and reduced health risk. Full article