Free Glutamic Acid Research Articles

Binding of Glutamic Acid to Silver and Gold Nanoparticles Investigated by Surface-Enhanced Raman Spectroscopy

Glutamate is the most important excitatory neurotransmitter, which is relevant for the study of several diseases such as amyotrophic lateral sclerosis and Alzheimer. It is the form L-glutamic acid (Glu) takes at physiologically relevant pHs. The surface-enhanced Raman spectra of Glu obtained at pH values ranging from 3.3 to 12 are collected in the presence of silver and gold colloids and on solid substrates. The observed bands are compared with the positions of calculated normal modes for free neutral glutamic acid, glutamic acid monohydrate, glutamic acid bound to gold and silver atoms, and sodium glutamate. Although gold atoms prefer to bind to the NH2 group as compared to carbonyl groups, silver atoms prefer binding to hydroxyl groups more than binding to the amino group. SERS spectra of glutamic acid solutions with a pH value of 12, in which both carboxylic groups are deprotonated, indicate a complexation of the glutamic acid dianion with the sodium cation, which was introduced into the solution to adjust the pH value. Further research towards an optimal substrate is needed.

Maternal cafeteria diet programs fecal microbiota and modulates serum fatty acid and amino acid levels in adulthood rats

Maternal food environment can program fecal microbiota in offspring mediated by the imprint of intrauterine conditions. Gut bacteria play a role in host fatty acid and amino acid metabolism. This study aimed to determine the effects of maternal diet on fecal microbiota, and the impact on fatty acid and amino acid metabolism in male offspring rats. Ten male pups from dams fed standard diet (C-C, n = 5) and cafeteria diet (Caf-C, n = 5) were fed standard chow diet for twenty-three weeks. Fresh fecal samples were collected at three and twenty-six weeks of age for fecal microbiota analysis by metagenomic sequencing of the V3-V4 region of the 16S rRNA gene. At the end of the study, serum samples were collected to analyse fatty acids from phospholipid and cholesterol ester fractions by gas chromatography and free amino acids by liquid chromatography. The bacterial abundance from the Actinobacteria and Proteobacteria phyla significantly decreased over time for both groups. Additionally, significant differences were found between C-C and Caf-C groups in these bacterial phyla. In the Caf-C group, Firmicutes and Elusimicrobia phyla increased, while Bacteroidetes decreases in adulthood samples. At the genus level, the abundance of Bacteroides decreased, while Elusimicrobium, Lactobacillus, Turicibacter, Blautia, and Veillonella increased in the Caf-C group. Several metabolites including PL-MCFAs (caprylic acid and capric acid), CE-MUFAs (palmitoleic acid and heptadecenoic acid), and free amino acids aspartate, glutamic acid, and cysteine were significantly higher in Caf-C group. This study underscores the putative programming of offspring fecal microbiota by maternal diet impact. These changes led to alterations fatty acids and amino acids metabolism in adult male offspring rats.

Valorization of Saithe (Pollachius virens) Residuals into Protein Hydrolysates-Silaging as Preservation Technology.

Silaging can be used as preservation technology to valorize currently discarded raw material into protein hydrolysate on board deep-sea vessels. The aim of this study was to investigate the effect of sorting and raw material freshness on the quality and yield of protein hydrolysates obtained through silaging of saithe (Pollachius virens) viscera. Additionally, the effect of using acid-containing antioxidants was tested. Out sorting of the liver prior to silaging resulted in slightly higher hydrolysate yields. The hydrolysates with the highest protein contents were obtained from silages made from fresh raw materials (day 0), and the content decreased significantly after longer storage of the raw material (2-3 days at 4 °C). Storage of the raw material for 1 day did not affect the quality. However, a significantly higher degree of hydrolysis (DH), content of free amino acids (FAA), and total volatile basic nitrogen (TVB-N) were obtained when raw materials were stored for 3 days. The FAA composition was influenced by the raw material's freshness, with increases in free glutamic acid and lysine and a decrease in free glutamine after longer storage. None of the studied parameters were significantly affected by out sorting of liver or the addition of antioxidants. Overall, the results indicate that the whole fraction of the viscera can be utilized without reducing the quality of the hydrolysate and that the raw material should be stored for a maximum of 1 day prior to preservation to optimize the quality.

Effect of different processing steps in the production of beer fish on volatile flavor profile and their precursors determined by HS-GC-IMS, HPLC, E-nose, and E-tongue

Beer fish is characterized by its distinctive spicy flavor and strong beer aroma. Currently, there is a lack of comprehensive research analyzing the changes in taste and volatile compounds that occur during the processing of beer fish. Thus, this study used HS-GC-IMS, electronic tongue, and electronic nose to investigate the changes in flavor components during various processing stages of beer fish. The obtained results were subsequently analyzed using multivariate statistical analysis. The results showed that the final beer fish product (SF) had the greatest amount of free amino acids (888.28 mg/100 g), with alanine, glutamic acid, and glycine contributing to the taste of SF. The inosine monophosphate (IMP) content of beer fish meat varied noticeably depending on processing stages, with deep-fried fish (FF) having the greatest IMP content (61.93 mg/100 g), followed by the final product (SF) and ultrasonic-cured fish (UF). A total of 67 volatiles were detected by GC-IMS, mainly consisting of aldehydes, ketones, and alcohols, of which aldehydes accounted for >37%, which had a great influence on the volatile flavor of beer fish. The flavor components' composition varied noticeably depending on the stage of processing. PLS-DA model screened 35 volatile flavor components (VIP > 1) as markers; the most significant differences were 1-propanethiol, isoamyl alcohol, ethanol, and eucalyptol. Ultrasonic processing, frying, and soaking sauce can significantly improve the formation of flavor compounds, resulting in a notable enhancement of the final beer fish's umami taste and overall flavor quality.

Correlation between microbial community succession and flavor substances during fermentation of Yongchuan Douchi

Yongchuan douchi (YCDC) is a traditional Chinese condiment famous for its distinct flavor and texture. This study utilized high-throughput sequencing to analyze the microbial community changes during YCDC fermentation and investigate the relationship between its physicochemical properties, flavor compounds, and microorganisms. The sequencing results revealed that Staphylococcus, Bacillus, Leuconostoc, Weissella, Streptophyta, Nocardiopsis, Aspergillus, Penicillium, Starmerella, and Zygosaccharomyces were the dominant bacteria during the YCDC fermentation process. The free amino acid (FAAs), glutamic acid (Glu), asparagine (Asp), and organic acid (citric and succinic acid) levels increased gradually throughout fermentation. Additionally, 29 key flavor compounds were identified, with lipids, alcohols, aldehydes, and acids significantly affecting the flavor profile. Network graph analysis demonstrated positive correlations between Staphylococcus, Escherichia_Shigella, Brevibacterium, and 1-octene-3-ol, ethyl isobutyrate, and benzaldehyde, respectively, contributing to light, fruity, and floral aromas. Moreover, bacterial genera exhibited stronger potential correlations with flavor compounds than fungal genera. These findings enhance the understanding of microbial community succession in YCDC and offer a theoretical basis for flavor strain selection.

Fine-tuning the flavor of Tetraselmis chuii by modifying nitrogen supply

Dried Tetraselmis chuii biomass has potential as flavoring agent for the development of plant-based seafood alternatives because of its seafood-like aroma and strong umami taste. Depending on the cultivation conditions, microalgae can adapt their metabolism, resulting in a change in biochemical composition. The aim of this study was to assess if the flavor of T. chuii could be modified by changing the nitrogen (N) supply in the cultivation medium in order to maximize the potential of T. chuii as flavoring agent. The sensory evaluation by a trained panel showed that the T. chuii biomass obtained from N starved cultivation conditions (N-deplete) is characterized by a significantly stronger odor intensity and earthy-like off-odor compared to T. chuii biomass obtained from N sufficient cultivation conditions (N-replete). The analysis of volatile organic compounds (VOCs) using SPME-GC–MS showed that these odor features of N-deplete biomass are attributed to an increased formation of odor-active VOCs including 2,3-butanedione, 3-methylbutanal, 3-methylbutanol and sulfur-containing dimethyl sulfide and dimethyl disulfide. In contrast, the T. chuii N-replete biomass possessed a significantly stronger taste intensity, umami and salty taste compared to the T. chuii N-deplete biomass. The higher umami is attributed to the significantly higher free glutamic acid (Glu) and adenosine monophosphate (AMP) concentrations in N-replete biomass compared to N-deplete biomass. This study illustrates that flavor and palatability of microalgae biomass is strongly affected by cultivating conditions and modifying these conditions can be an important tool in the development of plant-based seafood alternatives.

Amino acids profile of 56 species of microalgae reveals that free amino acids allow to distinguish between phylogenetic groups

Microalgae represent a phototrophic resource with a high protein content, whose nutritional value is very high as a result of its amino acid profile. Although the total amino acid profile has been repeatedly described to change little among phylogenetic groups of microalgae, some variability has occasionally been reported. Part of this uncertainty is associated with the low phylogenetic diversity encompassed in the work to date and the high methodological variability between studies. Among these studies, very few have differentiated between total and free amino acid content for common microalgae samples. Thus, in the present work, the profile of total and free amino acids has been determined in a diverse group composed of 56 species of microalgae belonging to 7 phyla. A multivariate analysis of the total amino acid profile in the studied microalgae group revealed close amino acid patterns throughout microalgae phylogeny and agreed with results obtained from similar analysis performed with published data. Conversely, the free amino acid profile strongly differentiated between phylogenetic groups. On the one hand, species of Cyanobacteria, Plantae, Cryptophyta, and Bacillariophyta showed close free amino acid patterns, characterized by the highest abundance of free glutamic acid. Ochrophyta species were particularly rich in free proline, while the free amino acid profile of Miozoa and Haptophyta species stood out from the rest of the phylogenetic groups for their outstanding levels of the two essential amino acids phenylalanine and lysine. Haptophyta species were also characterized by their much higher free tyrosine content.

Optimal temperature for culturing chicken satellite cells to enhance production yield and umami intensity of cultured meat

To investigate the optimal temperature at which to culture chicken muscle satellite cells (MSCs), to improve the production yield and umami intensity of cultured meat, chicken MSCs were cultured at 37, 39, 41, and 43 °C. The most active proliferation and greatest differentiation of MSCs was observed at 41 °C. A significantly shorter doubling time of MSCs and higher area percentage of differentiated myotubes and myofibers were observed at a culture temperature of 41 °C (p < 0.05). Consequently, the total amino acid content and free glutamic acid in cultured muscle tissue (CMT) at 41 °C was significantly higher than at other temperatures (p < 0.05). In addition, the umami and richness intensity of CMT was significantly higher at 41 °C than at other culture temperatures (p < 0.05). Results suggest that chicken MSCs proliferated more actively and differentiated optimally at 41 °C, resulting in a higher amino acid content and umami intensity of CMT.

Isolation of Debaryomyces hansenii and selection of an optimal strain to improve the quality of low-grade beef rump (middle gluteal) during dry aging.

The objective of this study was to evaluate the effect of Debaryomyces hansenii isolated from dry-aged beef on the tenderness and flavor attributes of low-grade beef during dry aging. Five D. hansenii strains were isolated from dry-aged beef samples. The rump of low-grade beef was inoculated with individual D. hansenii isolates and subjected to dry aging for 4 weeks at 5°C and 75% relative humidity. Microbial contamination levels, meat quality attributes, and flavor attributes in the dry-aged beef were measured. Of the five isolates, the shear force of dry-aged beef inoculated with SMFM201812-3 and SMFM201905-5 was lower than that of control samples. Meanwhile, all five isolates increased the total free amino acid, glutamic acid, serine, glycine, alanine, and leucine contents in dry-aged beef. In particular, the total fatty acid, palmitic acid, and oleic acid contents in samples inoculated with D. hansenii SMFM201905-5 were higher than those in control samples. These results indicate that D. hansenii SMFM201905-5 might be used to improve the quality of beef during dry aging.

Human milk nutritional composition across lactational stages in Central Africa.

The African region encompasses the highest undernutrition burden with the highest neonatal and infant mortality rates globally. Under these circumstances, breastfeeding is one of the most effective ways to ensure child health and development. However, evidence on human milk (HM) composition from African women is scarce. This is of special concern, as we have no reference data from HM composition in the context of food insecurity in Africa. Furthermore, data on the evolution of HM across lactational stages in this setting lack as well. In the MITICA study, we conducted a cohort study among 48 Central-African women and their 50 infants to analyze the emergence of gut dysbiosis in infants and describe the mother-infant transmission of microbiota between birth and 6 months of age. In this context, we assessed nutritional components in HM of 48 lactating women in Central Africa through five sampling times from week 1 after birth until week 25. Unexpectedly, HM-type III (Secretor + and Lewis genes -) was predominant in HM from Central African women, and some nutrients differed significantly among HM-types. While lactose concentration increased across lactation periods, fatty acid concentration did not vary significantly. The overall median level of 16 detected individual human milk oligosaccharides (HMOs; core structures as well as fucosylated and sialylated ones) decreased from 7.3 g/l at week 1 to 3.5 g/l at week 25. The median levels of total amino acids in HM dropped from 12.8 mg/ml at week 1 to 7.4 mg/ml at week 25. In contrast, specific free amino acids increased between months 1 and 3 of lactation, e.g., free glutamic acid, glutamine, aspartic acid, and serine. In conclusion, HM-type distribution and certain nutrients differed from Western mother HM.

Post-harvest quality changes and shelf-life determination of washed and blanched sugar kelp (Saccharina latissima)

Sugar kelp (Saccharina latissima) is a native European brown macroalga with the potential to become a vital part of the green transition of the food industry. Knowledge of the sugar kelp shelf-life is essential to designing the food supply chain to ensure safe and high-quality food. Establishing a single-compound quality index (SCQI) of freshness would be useful for the industry. However, information is currently lacking on how different post-harvest treatments affect the shelf-life of sugar kelp, even though it is important knowledge for manufacturers, authorities and consumers. The objective of this study was to establish the shelf-life of refrigerated sugar kelp following five post-harvest treatments and evaluate the effect of these treatments on changes in quality attributes (sensory, microbial, chemical and physical) during storage to select the SCQI. The post-harvest treatments included washing in sea water, washing in potable water, blanching for 2 min in sea water or potable water and untreated sugar kelp. Based on sensory analysis, the refrigerated (+ 2.8°C) shelf-lives for sugar kelp from all treatments were seven to 9 days. The end of the sensory shelf-life correlated with the development of &amp;gt;7 log (CFU g−1) aerobic viable counts, suggesting this attribute can be used as a SCQI to evaluate the shelf-life of sugar kelp. The microbiota was dominated by putative spoilage organisms from the Pseudoalteromonadaceae and Psychromonadaceae families. Untreated and washed sugar kelp continued to respire and consume carbohydrates up to 5 days post-harvest, indicating respiration rates may be used to determine freshness of non-blanched kelp. Favorable organoleptic properties, e.g., sweetness and umami, decreased during storage and coincided with a reduction in water-soluble mannitol and free glutamic acid. Both blanching treatments changed texture and color and reduced iodine and vitamin C contents while retaining components such as fucoxanthin, chlorophyll a and β-carotene. This study provides crucial documentation of quality changes during the post-harvest storage period of sugar kelp, including information about sugar kelp spoilage and nutrient changes, which would facilitate the development of best practices for manufacturers using sugar kelp in their production of food.

Determination of flavor-potentiating compounds in different Italian tomato varieties.

Umami taste, known as appetizing sensation, is mainly imparted by monosodium glutamate (MSG, the first identified umami factor) in synergistic combination with some 5' ribonucleotides such as inosine 5'-monophosphate, IMP, guanosine 5'-monophosphate, GMP, and adenosine 5'-monophoshate, AMP. The level of free glutamic acid in tomatoes is higher than in other vegetables or fruits and increases with ripening and industrial processing. In addition, due to the presence of bioactive metabolites, tomatoes and tomato-based products are among the most consumed healthy food items. The levels of the major umami compounds of tomato, that is, glutamate and 5'-ribonucleotides (GMP and AMP) were assessed in different parts (skin, outer flesh, and inner pulp) of known tomato varieties from southern Italy: San Marzano Originale, San Marzano 245, Black Tomato, Corbarino Corbara, Corbarino Nocera, and Superpomodoro (tomato hybrid). Such varieties were also investigated for their antioxidant properties through DMPD, DPPH, and ABTS assays, with San Marzano Originale showing the highest antioxidant power both in lipophilic and methanolic fractions. The concentration of umami compounds in tomato differs with the part of the fruit analyzed and is greatly dependent on the variety, being Corbarino Nocera the cultivar richest in glutamate and Superpomodoro in ribonucleotides. As for nutritional aspect, results confirm the great nutraceutical feature of San Marzano tomato, the most known variety used in industrial processes. PRACTICAL APPLICATIONS: This study was planned to develop a method to quantify the major umami compounds that strongly influence the organoleptic properties of many different tomato varieties. It is known that the sensory quality of fruits and vegetables is an important factor in consumer's choice. The analytical methods described here enabled the evaluation of the glutamate and 5'-ribonucleotides contents in six selected varieties of tomato from Campania region, and can be easily used to determine the sensory profile of commercial varieties, for example, those perceived as not very tasteful by consumers.

Molecular characterization of a novel aspartyl aminopeptidase that contributes to the increase in glutamic acid content in chicken meat during cooking

The enzyme involved in the increase in glutamic acid content in chicken meat during cooking was identified and characterized. Chicken homogenate produced significantly more free glutamic acid and exhibited higher glutamyl p-nitroanilide (Glu-pNA) hydrolyzing activity than beef when heat cooked. Amino acid sequencing revealed the presence of aspartyl aminopeptidase (DNPEP) in chicken meat. Using RT-PCR, DNPEP gene expression was detected in chicken breast and thigh muscles, liver, and small intestine, together with various other peptidase genes. Full-length DNPEP cDNA was cloned, and recombinant chicken DNPEP (cDNPEP) was expressed in Escherichia coli. cDNPEP showed five-fold higher activity against Glu-pNA than against aspartyl-pNA, which represents a different substrate specificity than observed for recombinant bovine DNPEP (bDNPEP). The Km values of both DNPEPs with Glu p-NA substrates indicated a higher affinity of cDNPEP for glutamyl residues. This unique substrate specificity of cDNPEP contributes to efficient glutamic acid production in chickens.

Evaluation of using a combination of enzymatic hydrolysis and lactic acid fermentation for γ-aminobutyric acid production from soymilk

The production of fermented foods enriched with γ-aminobutyric acid (GABA) is a current trend in the food industry. In this study, the release of free glutamic acid (Glu) and its conversion to GABA in soymilk were conducted through enzymatic hydrolysis using Alcalase (Al) and Flavourzyme (Fl), following by the fermentation using Lb. plantarum LMG6907 (at 30 °C for 96 h). Results showed that a degree of hydrolysis of 90% was achieved when soymilk was treated with a mixture of Al:Fl in a ratio 1:1 (final enzyme concentration of 2 mL/100 mL). Both the free Glu and the GABA content were significantly increased in soymilk hydrolysate, which is a product obtained after enzymatic hydrolysis of soymilk. After 72 h of fermentation, the GABA content in soymilk hydrolysate reached 859 mg/L while the remaining Glu was 2467 mg/L. Fermentation of soymilk hydrolysate at the optimal conditions for glutamate decarboxylase activity (initial pH 4.7, 50 °C), the enzyme catalyzing the conversion of Glu to GABA, also did not show a higher GABA production.

Could Free Glutamic Acid in Processed Food be the Surprise Ingredient in Mood Disorders?

Keywords glutamate, excitotoxicity, mood disorders, manufactured free glutamate, glutamate neurotransmitters

The Effects of Total Mixed Ration Feeding with High Roughage Content on Growth Performance, Carcass Characteristics, and Meat Quality of Hanwoo Steers.

This study investigated the dietary effect of total mixed ration (TMR) based on high roughage content on the growth performance, carcass characteristics, and meat quality of Hanwoo steers. Twenty-four Hanwoo steers (average body weight, 195.3±4.7 kg; age, 8.5 mon) were randomly allocated to three experimental groups according to forage and concentrate ratio (DM basis): 25:75 (control), 50:50 (T50), and 70:30 (T70). Productivity in the fattening period and final body weight were significantly higher in the control. Average daily gain and feed conversion ratio were the same among treatments. Serum parameters, cholesterol, blood urea nitrogen, and total protein were higher in the control. Carcass weight was comparable in the control and T50 but feeding more roughage was significantly correlated with a higher intramuscular fat. Shear strength and drip loss were higher while n-6/n-3 was lower in T70 compared to the other groups. However, meat color was not significantly different among treatments. In terms of free amino acid contents, glutamic acid and glycine were higher in the control than T50 and T70. Overall, feeding Hanwoo steers with high forage content TMR had the lowest n-6/n-3 ratio of fatty acid content but highest intramuscular fat, shear strength, and drip loss. High forage content TMR is the best feed for Hanwoo steers that gives more benefits for human health and consumption but also provides the best meat grade and quality, which is important in the beef market in Korea.

Biogenic amine formation in fish roe in under the effect of drying methods and coating materials

The effects of drying methods (freeze-drying, fluidized bed-drying) and coating materials (gelatin, alginate, pectin) on the formation of biogenic amines (BAs) in fish roe were determined. The relationship between BAs content and free amino acid (FAA) profiles were monitored for 6 months. Lysine (282.5–385.0 mg/kg), leucine (258.5–319.1 mg/kg), phenylalanine (211.9–316.0 mg/kg) and isoleucine (208.8–312.8 mg/kg) were the most abundant free essential amino acids, whereas aspartic acid (498.3–742.6 mg/kg) and glutamic acid (420.9–620.7 mg/kg) constitute a big amount of nonessential FAAs in dried roes. High amino acid content was obtained in gelatin coated samples. The main BAs were putrescine, spermine and spermidine and all increased significantly (p < .01) with the storage time. High positive correlation was observed between free glutamic acid content and putrescine (0.91) and spermine (0.94) formation. Freeze-drying was successful in suppression the formation of BAs. Alginate and gelatin were better coating materials in terms of inhibiting microbiological growth. Practical applications The formation of BAs is a problem in seafood, especially during storage. Fish roe has abundant free amino acids such as lysine, leucine and phenylalanine that enables to form BAs. The main biogenic amines of trout roe were putrescine, spermine and spermidine. The formation of biogenic amines was hindered by freeze-drying method. Moreover, alginate and gelatin coatings were successful in suppression the microbial growth.

Comparison of γ‐aminobutyric acid accumulation capability in different mung bean (Vigna radiata L.) varieties under heat and relative humidity treatment, and its correlation with endogenous amino acids and polyamines

SummaryIn this study, the accumulation of GABA and its inherent factors across different varieties of mung bean (Vigna radiata L.) in response to heat and relative humidity (HRH) were investigated. Results showed the average GABA content in mung bean varieties was increased 7.52 times following HRH treatment, and the black mung bean variety (A8) exhibited the highest GABA accumulation capability (1.76–84.57 mg per 100 g DW). From the perspective of GABA shunt metabolites, the free glutamic acid content of mung beans significantly decreased (P &lt; 0.05) after HRH treatment and presented a significant correlation (P &lt; 0.05) with GABA content. In polyamine degradation pathway, although the average levels of spermine and spermidine of mung bean varieties significantly decreased (P &lt; 0.05) after HRH treatment, no significant correlation with GABA content was identified. Hence, the GABA accumulation was predominantly attributed to GABA shunt. Besides, free amino acids including glutamic acid, serine, ornithine, arginine and glycine in mung beans showed a significant positive correlation (P &lt; 0.05) with GABA content and increment following HRH treatment, which suggested that mung beans enriched in these free amino acids might accumulate higher amounts of GABA after HRH treatment and be useful for industrial applications.

Effect of long-term dietary probiotic Lactobacillus reuteri 1 or antibiotics on meat quality, muscular amino acids and fatty acids in pigs

This study investigated effects of 175-d dietary treatment with Lactobacillus reuteri 1 (LR1) or antibiotics (olaquindox and aureomycin) on the longissimus thoracis (LT) of pigs. Results showed that antibiotics decreased pork quality by increasing drip loss, shear force, and altering myofiber characteristics including diameter, cross-sectional area and myosin heavy chain isoforms compared to LR1. Pigs fed antibiotics had lower muscle contents of free glutamic acid, inosinic acid, and higher glutamine compared to pigs fed the controls and LR1 diets (P ≤ .05). Furthermore, antibiotics decreased free isoleucine, leucine, methionine in LT compared to the control (P ≤ .05). Compared to antibiotics, LR1 likely improved protein synthesis by modulating expression of amino acid transport and ribosomal protein S6 kinase 1 (S6K1) genes, and altered fatty acid profile by regulating metabolic pathways. Overall, LR1 improved pork quality compared to antibiotics by decreasing drip loss and shear force, increasing inosinic acid and glutamic acid that may improve flavor, and altering muscle fiber characteristics.

Effect of Inlet Air Temperature on the Properties of Spray Dried San-sakng (Albertisia papuana Becc.) Leaf

Free glutamic acid is a flavor enhancer compound that provided umami taste. San-sakng (Albertisia papuana Becc.) leaf has been used as a seasoning in the Dayaks tribe, West Kalimantan, Indonesia. The aim of this study was evaluated the effect of different drying inlet air temperature on physico-chemical of the spray dried san-sakng leaf. San-sakng leaf powders was produced using spray drying and maltodextrin as raw material. Completely randomized design was used with one factor, namely drying inlet air temperature on the spray drying process (130°C, 140°C, and 150°C). The results showed that moisture, solubility, bulk density, particle size, and encapsulation efficiency on the San-sakng leaf powders presented significantly affected by the drying inlet air temperature. Increasing inlet air temperature led to reduced moisture, bulk density, and particle size, whereas enhancing the solubility and encapsulation efficiency.