Scielo RSS <![CDATA[Food Science and Technology (Campinas)]]> vol. 37 num. 1 lang. pt <![CDATA[SciELO Logo]]> <![CDATA[Volatile compounds in meat and meat products]]> Abstract Meaty flavor is composed of a few hundreds of volatile compounds, only minor part of which are responsible for the characteristic odor. It is developed as a result of multi-directional reactions proceeding between non-volatile precursors contained in raw meat under the influence of temperature. The volatile compounds are generated upon: Maillard reactions, lipid oxidation, interactions between Maillard reaction products and lipid oxidation products as well as upon thiamine degradation. The developed flavor is determined by many factors associated with: raw material (breed, sex, diet and age of animal, conditions and process of slaughter, duration and conditions of meat storage, type of muscle), additives applied and the course of the technological process. The objective of this review article is to draw attention to the issue of volatile compounds characteristic for meat products and factors that affect their synthesis. <![CDATA[Deoxynivalenol in wheat and wheat products from a harvest affected by fusarium head blight]]> Abstract Fusarium head blight is an important disease occurring in wheat, caused mainly by the fungus Fusarium graminearum. In addition to direct damage to crops, reduced quality and yield losses, the infected grains can accumulate mycotoxins (toxic metabolites originating from prior fungal growth), especially deoxynivalenol (DON). Wheat crops harvested in 2014/2015 in southern Brazil were affected by high levels of Fusarium head blight. In this context, the aim of this study was evaluate the mycotoxicological quality of Brazilian wheat grains and wheat products (wheat flour and wheat bran for DON. DON contamination was evaluated in 1,504 wheat and wheat product samples produced in Brazil during 2014. It was determined by high performance liquid chromatograph fitted to a mass spectrometer (LC-MS / MS). The results showed that 1,000 (66.5%) out of the total samples tested were positive for DON. The mean level of sample contamination was 1047 µ, but only 242 samples (16.1%) had contamination levels above the maximum permissible levels (MPL) - the maximum content allowed by current Brazilian regulation. As of 2017, MPL will be stricter. Thus, research should be conducted on DON contamination of wheat and wheat products, since wheat is a raw material widely used in the food industry, and DON can cause serious harm to public health. <![CDATA[Characterization of chemical and mineral composition of marolo (<em>Annona crassiflora</em> Mart) during physiological development]]> Abstract Maroleiro (Annona crassiflora Mart), belonging to the family of Annonaceae is a typical specie of the Cerrado and has occurred in most states. For fruit characteristics “sui generis”, with significant nutritional value. This study aimed to characterize the marolo (Anonna crasiflora Mart) during fruit development, through the evaluation of its proximal and mineral composition. The fruits 2012/2013 season, were picked to 12Km from the city of Itumirim, southern Minas Gerais, in intervals of 20 days from anthesis to maturity, and the first fruits were harvested 60 days after anthesis. The flowering marolo began in late September 2012, with fruiting initially observed at the end of October, with peak production at the end of February and beginning of March 2013 The fruits were harvested in the morning and carried to the laboratory, where followed up the moisture, ether extract, protein, ash, fiber and high sugar fraction beyond mineral quantification of them. During development reductions in moisture content and protein increments of ether extract, crude fiber and high sugar fraction and an oscillation in the mineral along the developmental stages was observed. <![CDATA[Utilization of residue from cassava starch processing for production of fermentable sugar by enzymatic hydrolysis]]> Abstract The aim of this study was to characterize and perform enzymatic hydrolysis of cassava peeling residue (peel and inner peel), mainly composed of peels and small pieces. Residue was sanitized, dried at 55 °C for 24 hours and ground. The obtained flour showed pH of 4.85; 72.53 g 100 g–1 moisture; 5.18 mL 1M NaOH 100 g–1 acidity; 60.68 g 100 g–1 starch; 1.08 g 100 g–1 reducing sugar; 1.63 g 100g–1 ash; 0.86 g 100 g–1 lipid and 3.97 g 100 g–1 protein. Enzymatic hydrolysis was carried out by means of rotational central composite design, analyzing the effects of concentrations of α-amylase enzyme (10 to 50 U g starch–1), and the amyloglucosidase enzyme (80 to 400 U g starch–1) on variable responses: percent conversion of starch into reducing sugars (RSC) and soluble solid content (SS). Highest values of RSC (110%) and SS (12 °Brix) were observed when using the maximum concentration of amyloglucosidase and throughout the concentration range of α-amylase. Enzymatic hydrolysis of cassava peel is feasible and allows the use of hydrolysate in fermentation processes for the production of various products, such as alcoholic drinks, vinegar, among others. <![CDATA[The effect of the replacement of fat with carbohydrate-based fat replacers on the dough properties and quality of the baked pogaca: a traditional high-fat bakery product]]> Abstract Pogaca is a traditional high-fat bakery product in Turkey. This study was conducted to evaluate the effect of fat replacement in pogaca formulation by various amounts (5, 10 and 15 g on 100 g wheat flour basis) of inulin, polydextrose and maltodextrin on the properties of dough and quality of pogaca. Dough stickiness values were increased by increasing the amount of fat replacer at the all fat reduction levels (20, 30 and 40%) studied. Extensibility and resistance to extension values of dough were also significantly changed due to the fat replacement. Sensory analysis of pogaca showed that the formulations prepared by maltodextrin and polydextrose generally received higher scores than the formulation prepared by inulin. Overall, it was observed that up to 30% of the fat can be replaced in pogaca formulation without any decrease in the physical, textural and sensory quality of pogaca. <![CDATA[Characterization of bioactive compounds, antioxidant activity and minerals in landraces of pumpkin (<em>Cucurbita moschata</em>) cultivated in Southern Brazil]]> Abstract The objective of this work was to evaluate the genetic variability for the synthesis of bioactive compounds and minerals in pumpkin (Cucurbita moschata) landraces. Total phenolic compounds, carotenoids, antioxidant activity and minerals were evaluated in 10 accessions of Cucurbita moschata landraces from the Genebank of Embrapa Temperate Agriculture (Pelotas - RS, Brazil). Twenty plants of each accession were cultivated in the field during the spring/summer of 2013/2014. After harvesting of mature fruits, the seeds were discarded and opposite longitudinal portions of the pulp were manually prepared for analysis of the bioactive compounds. For the determination of minerals, pumpkin samples were frozen in plastic bags, and after freeze-dried and milled. All analysis were performed in triplicate. The data obtained showed high genetic variability for the synthesis of phenolic compounds, carotenoids, antioxidant activity and minerals. The accessions C52, C81, C267 e C389 showed high levels of antioxidants and minerals, being recommended for use in pumpkin breeding programs. The accessions C52 and C389 are promising, especially because they present the highest levels of total carotenoids. <![CDATA[Occurrence of non-O157 Shiga toxin-encoding <em>Escherichia coli</em> in artisanal mozzarella cheese in Brazil: risk factor associated with food workers]]> Abstract Mozzarella cheese is considered a safe food due to the high temperature treatment used in the traditional process of stretching into hot water; however, a post-process contamination during the cheese manufacture or during the processing (before distribution) could occur. This study investigated the occurrence of Shiga toxin-encoding Escherichia coli (STEC) strains in homemade-mozzarella cheese. In total, 59 raw milk cheese samples collected at a local producer in the Jequitinhonha Valley (Northeast of Minas Gerais, Brazil) were submitted for microbiological analysis, and 38 (64.4%) tested positive for E. coli. Then, 147 strains of E. coli were isolated from positive samples and screened by polymerase chain reaction for the presence of the genes encoding the following virulence factors: stx1 and stx 2 (verotoxin types 1 and 2) and eae (intimin). All the isolates were negative for the stx 2, 14 isolates (9.5%) were positive for the stx1 gene, and 11 of them also harbored the eae gene. A food worker was probably involved in cheese contamination during the manufacture schedule. While the development of STEC infection in humans is not completely understood, all STEC- contaminated food can be considered potentially hazardous. <![CDATA[A study of fortification of lemonade with herbal extracts]]> Abstract The aim of the present work was to design new beverages using lemonade and some herbal extracts (linden, heather, green tea, lemon verbena, clove, peppermint, ginger and mate) rich in vitamin C and flavonoids. The linden-added lemonade showed the highest value (597.9 mg/kg) for ascorbic acid content, whereas the lemon verbena-added lemonade showed the lowest value (486.04 mg/kg). The amount of saccharose was changed by 11.07-11.58%, the glucose by 1.11-1.62% and the fructose between 11.07-11.58% in the beverages. K, Na, Mg and P values in the lemonades were determined in the range of 178.83-210.98 mg/kg, 33.75-39.13 mg/kg, 22.37-27.89 mg/kg and 7.22-10.04 mg/kg, respectively. The total phenolic content in the samples changed between 315.11-397.57 mg GAE/100 g. When the samples were analyzed for antioxidant activity, FRAP (17.13-26.79 µmol trolox/mL) and ABTS (16.91-25.38 µmol trolox/mL) methods gave higher results than the DPPH (14.88-17.72 µmol trolox/mL) method. Linden-, ginger- and peppermint-added lemonades, which had been found to be rich in total phenolic compounds and ascorbic acid, showed higher antioxidant activity than the control sample. Overall, the most preferred lemonades were heather- and ginger-added beverages and the control sample. Mate-added lemonade was the least preferred. <![CDATA[Effect of different periods of pre-slaughter stress on the quality of the Nile tilapia meat]]> Abstract The study was carried out with the objective of evaluating the influence of pre-slaughter stress on meat quality of Nile tilapia (O. niloticus) for 10 days of storage in ice. 75 whole fish were used eviscerated, with average weight and length of 825.75 ± 101.59 g and 28.25 ± 0.81 cm, respectively. The treatments consisted of time in which the animals underwent pre-slaughter hypoxia, being 0, 3 and 6 minutes. Rigor mortis and muscle pH were assessed besides the application of the Quality Index Method and analysis of total protein and blood glucose. Rigor mortis did not differ among treatments during the storage period, and after three hours all animals were in rigor stage. The muscle pH values varied widely during the study period, observing higher values on the third day of storage. Sensory analysis showed that after 10 days the tilapia from the different treatments did not differ in the evaluated quality parameters similarly, there was no difference regarding the evaluated blood biochemical parameters Thus, hypoxia of 6 minutes pre-slaughter does not influence the rigor mortis, muscle pH, qualitative perception of the meat quality, total protein and blood glucose of Nile tilapia. <![CDATA[Management of freezing rate and trehalose concentration to improve frozen dough properties and bread quality]]> Abstract Bread is one of the most consumed foods in the world, and alternatives have been sought to extend its shell life, and freezing is one of the most popular methods. The purpose of this study was to evaluate the effect of freezing rate and trehalose concentration on the fermentative and viscoelastic properties of dough and bread quality. Dough was prepared and trehalose was added at three concentrations (0, 400, 800 ppm); dough was pre fermented and frozen at two freezing rates then stored for 42 days. Frozen dough samples were thawed every two weeks. CO2 production and elastic and viscous modulus were determined. In addition, bread was elaborated and specific volume and firmness were evaluated. High trehalose concentrations (400 and 800 ppm) produced dough with the best viscoelastic and fermentative properties. Greater bread volume and less firmness were observed when a slow freezing rate (-.14 °C/min) was employed. <![CDATA[Availability and consumption of fish as convenience food – correlation between market value and nutritional parameters]]> Abstract Fish consumption is low in Brazil and several factors justify this fact, among them the lack of practicality in preparation. Thus, this study aimed to investigate the relation between the price and the nutritional characteristics of the processed fish products. Correlations between price and nutritional value of 18 different processed fish products were established, comparing nutritional parameters between in natura and processed fish. The results showed that protein features moderate positive correlation to price. The processed fish products analyzed showed lower protein content and higher contents of energy, lipids and sodium compared to in natura fish. <![CDATA[Processing potential of jellies from subtropical loquat cultivars]]> Abstract To increase the availability to consumers and add more value to loquat (Eriobotrya japonica Lindl.), which is a very perishable and seasonal fruit, and in order to identify which cultivars grown in subtropical regions are more suitable for jelly processing, the objective of this study was to evaluate the influence of different loquat cultivars (Fukuhara, Kurisaki, Mizumo, Mizuho and Mizauto) grown in subtropical regions of Brazil on the physicochemical characteristics, rheological properties and sensory acceptance of the resulting jelly. Based on sensory acceptance the most suitable loquat cultivars for jelly processing are Kurisaki and Mizuho. In this study it was found that the consumer prefers a more acidic, less sweet, less firm or softer loquat jelly, clearer with a more intense red color. <![CDATA[Histamine production by <em>Enterobacter aerogenes</em> in chub mackerel (<em>Scomber japonicus</em>) at various storage temperatures]]> Abstract Growth of Enterobacter aerogenes and accumulation of histamine in chub mackerel (Scomber japonicus) were investigated through measuring bacterial count, histidine decarboxylase (HDC) activity and histamine content in fish samples stored at various temperatures from 4 to 37 °C. Results showed that bacterial count and HDC activity rapidly increased in chub mackerel inoculated with E. aerogenes at storage temperature above 20 °C and reached the highest values (8.64 log CFU/g and 31.68 U/g) at 37 °C. Meanwhile, fish samples stored at 25 and 37 °C for 18 h, formed histamine at above 50 mg/100 g of the potential hazard level. In contrast, bacterial growth and histamine formation were controlled for 36 h by cold storage at low temperature (4 °C). Therefore, strict temperature control was necessary for preservation and processing of chub mackerel in order to assure this marine fish safety. <![CDATA[Characterization of Turkish honeys regarding of physicochemical properties, and their adulteration analysis]]> Abstract This work was conducted to evaluate the quality of 54 honey samples from eighteen different origins from Turkey. Physicochemical properties were examined according to AOAC methods, total phenolic and flavonoid contents by a spectrophotometric method and authenticity of honeys by Combustion Module - Cavity Ring-Down Spectroscopy (CM-CRDS). The microscopic analysis of honey sediment (mellissopalynology) was carried out to identify and count the pollen to provide qualitative indicators to confirm botanical origin. The moisture, electrical conductivity and free acidity of honeys ranged from 15.56 to 18.39%, 0.143 to 2.006, 16.05 and 34.10, respectively. Diastase activity of sideritis honey was found highest. Honeys showed HMF level below 40 The highest proline was determined in thyme honey. The results showed that honeys contained eminent amounts of phenolics and flavonoids. δ13C values of honeys were more negative than -23.5‰. The C4% sugar ratios were lower than 7% value. The lowest glucose-fructose content was observed in eucalyptus, cedar and pine honey samples. The results obtained for physicochemical characteristics, total phenolic and flavonoid contents an authenticity analysis of Turkish honeys indicate a good quality level, adequate processing, good maturity and freshness. The discrimination between honey types was achieved by PCA. <![CDATA[Biochemical assessment of oxidative stress by the use of açai (Euterpe oleracea Martius) gel in physically active individuals]]> Abstract The relation between oxidative stress and inflammation induced by diseases and exercise has increased the interest in the benefits of antioxidant supplements in the improvement of health and physical and mental performance. The aim of this study was to evaluate the effectiveness of açai gel in reducing oxidative stress in individuals engaged in physical activities as well as their acceptance. Sensory evaluation was performed to determine its acceptability and the biochemical parameters related to immune profile and biomarkers of muscle, liver and oxidative stress, with and without the use of gel were evaluated. The appearance, sweetness and overall impression of the açai gel were considered good. It was observed a significant increase in CK enzyme, without the gel as well as the oxidative stress biomarkers, it was observed that the MDA (with and without gel) a significant increase (p &lt; 0.05). Through biochemical evaluation, it is concluded that the gel provided protection for some of parameters studied, since it modulated the immunological parameter reducing the lymphocyte activity and muscular stress. However, more studies must be carried out with a larger number of individuals to confirm the gel functionality. <![CDATA[Retrogradation of heat-gelatinized rice grain in sealed packaging: investigation of moisture relocation]]> Abstract The aggregation of water molecules inside heat-gelatinized rice grain due to retrogradation of the grain was investigated by textural change and scanning electron microscopy (SEM) analysis of cooked grains after storage at 11 °C in a sealed package. Relaxation tests using a disc-type tip showed an increase in hardness (strength) of the cooked grain as the degree of retrogradation increased with increasing storage time, measured by the α-amylase–iodine method. SEM analysis of the vacuum-dried cooked rice grain showed a gradual increase in crevices, which further developed into holes at the center of the granule with increasing storage time. The results suggest that the disruption of hydrogen bonds between water and starch molecules is the first step for the retrogradation of gelatinized rice grain stored in a hermetic environment to avoid drying, resulting in its increased hardness, followed by the aggregation of starch molecules with subsequent water extrusion. <![CDATA[Occurrence of toxigenic <em>Aspergillus flavus</em> in commercial Bulgur wheat]]> Abstract Aflatoxins are mutagenic, carcinogenic, and teratogenic mycotoxins. The objective of this work was to study the presence of aflatoxigenic Aspergillus in commercial Bulgur wheat in the city of Maringá, Paraná, Brazil. Thirty samples of commercial Bulgur wheat, acquired in the period of August 2011 to January 2012, were evaluated. The enumeration analysis showed that samples had up to 273.3 CFU of molds and 133.3 CFU of aflatoxigenic Aspergillus per gram of wheat. Forty-two monosporic isolates were obtained and identified as Aspergillus flavus. The isolates were analyzed regarding their aflatoxigenic potential by culture in coconut milk agar; hydroxide vapor exposure; chromatography; and polymerase chain reaction (PCR) targeting genes that code enzymes of the aflatoxins synthesis pathway. Some of the isolates were confirmed to be aflatoxin producers and several of them presented a genetic profile of aflatoxin synthesis. The obtained results demonstrated that Bulgur wheat A. flavus contamination is concerning. <![CDATA[Modelling the effect of temperature on the water sorption isotherms of chitosan films]]> Abstract The interaction of the water molecules from the environment with foods and other materials can be evaluated using sorption isotherms. Films and biodegradable films are susceptible to changes in their functional characteristics due to adsorbed water. The amount of moisture that biodegradable films can adsorb depends on the temperature, relative humidity of the storage area and chemical composition. Several mathematical models can be used to describe the behavior of sorption isotherms in biodegradable films and some of them have been modified to include the temperature parameter into the equation. In this research, the original and modified BET, GAB, Halsey, Henderson and Oswin models were assessed to determine their suitability describing the behavior of moisture adsorption isotherms of chitosan films at 15, 20, 25 and 30 °C. The modified models of GAB, Oswin and Halsey gave the best fit to the experimental sorption data of the chitosan films, with R2 values higher than 0.97 demonstrating that those models describe better the sorption isotherms at the temperatures studied. <![CDATA[Kinetics of color change of osmotically dehydrated chub mackerel (<em>Scomber japonicus)</em> during storage at different temperatures]]> Abstract The aim of this study was to determine the effect of storage temperature on the kinetics of color change of chub mackerel dehydrated in a ternary solution (water, glycerol and salt) and vacuum packaged in films. The color of processed fish can change because of lipids and protein oxidation during storage. Samples were stored at 7, 25 and 35 °C for seven months and kinetic models of 0, 1 and 2 order were applied to describe the color changes. It was observed that an increase in the storage temperature improved the changes in the CIE color values (L*, a* and b*). First-order reaction had the best statistical parameters for a* at the three temperatures tested. The temperature dependence of parameter a* indicated an Arrhenius relationship and the activation energy (Ea) was 44.33 kJ/mol. The parameter b* fitted to the proposed models only in samples stored at 35 °C. The L* value decreased during storage at 25 and 35 °C (pale to dark). Storage at refrigeration temperature (7 °C) minimized the color changes. <![CDATA[Extraction of β-glucan from <em>Saccharomyces cerevisiae</em>: Comparison of different extraction methods and <em>in vivo</em> assessment of immunomodulatory effect in mice]]> Abstract Beta-glucan (BG) is a conserved cell wall components of bacteria, fungi, and yeast. BG is an immunomodulator and stimulates the host immune system. This study was performed to screen Saccharomyces cerevisiae strain with high BG, extraction of BG using different chemical extraction methods, composition analysis of BG, and evaluation of the immunomodulatory effect of high-quality BG using mice model. Ten yeast strains were screened for high BG content using total glucan extraction kit and were subjected to FT-IR analysis. The kit based extraction revealed that HII31 showed a high content of total glucan and BG. HII31 cells were subjected to four different acid/base extractions, which indicated that combination of a strong base (NaOH) and weak acid (CH3COOH) extraction recovered high BG and a high ratio of polysaccharide, protein, and lipid. Further, the immunomodulatory effect of the selected BG was evaluated using mice, which suggested that low dose of HII31-BG induces the expression of selected pro-inflammatory (IL-17, IFN-γ) and anti-inflammatory cytokine (IL-10) significantly, whereas relatively high dose was required to alter the IL-6 and TGF-β expression. Overall, the present study revealed that BG extracted from HII31 cells alters the expression of studied cytokines, which can be used as a potent immunomodulator in pharmaceutical products. <![CDATA[Physicochemical characterization and label comparison among diet yogurts sold in the city of Limoeiro do Norte – CE]]> Abstract This work aimed at analyzing labels (based on the current legislation) and confirm the nutritional information given on the label of five brands of diet yogurt. The physicochemical analyses carried out were: moisture, minerals, proteins, lipids, reducing carbohydrates in lactose, non-reducing carbohydrates in sucrose, total carbohydrates, acidity and pH. All brands of diet yogurt had mandatory nutritional information on their label. As for content, only brands B and C are compliant with the current legal demands. The numbers found in the analyses for protein and carbohydrates were higher than the percentages shown on the labels in all brands. There were no numbers for lipids. Despite the differences found on the labels, all brands of diet yogurt are in accordance with the Identity and Quality Standards for Fermented Milk as for protein, acidity and fat content. There was a significant difference in the complementary analyses for moisture, minerals and acidity. Nevertheless, the numbers assigned to carbohydrates and protein were lower than the actual values determined in lab and, in some brands, carbohydrates were three times higher. Thus, despite presenting all the necessary information on the label, the companies are not concerned about showing the correct nutritional data to consumers. <![CDATA[A comparative study on antioxidant activity of different parts of lotus (<em>Nelumbo nuficera</em> Gaertn) rhizome]]> Abstract In this study, the antioxidant activities of different parts of lotus (Nelumbo nuficera Gaertn) rhizome were compared. The total phenolic content of lotus rhizome was determined, and Ferric reducing antioxidant power (FRAP) assay, 1,1-diphenyl-2-picrylhydrazyl hydrate (DPPH) radical-scavenging assay and β-carotene-linoleic acid assay were performed to assess the antioxidant activity of lotus rhizome. Results showed that there was a significant difference in total phenolic content and antioxidant activity between any two of four parts of lotus rhizome. The order of total phenolic content and antioxidant activity in different parts of lotus rhizome was as follows: peel of old lotus rhizome &gt; peel of young lotus rhizome &gt; flesh of old lotus rhizome &gt; flesh of young lotus rhizome. The total phenol content is significantly positive correlated with the antioxidant activity in different parts of lotus rhizome. This study has provided a basis for further exploring the antioxidant components in lotus rhizome. <![CDATA[Total phenolics, antioxidant capacity, colour and drying characteristics of date fruit dried with different methods]]> Abstract Date slices were dried with the three drying methods convective (60, 70 and 80 °C), microwave (120 W) and freeze drying to determine drying characteristics and to compare the dried fruit quality. All colour parameters changed depending on the drying method and colours closest to the fresh sample were obtained with freeze drying. It is interesting to note that the total phenolic content and antioxidant capacity in each sample rose when looked at in relation to the fresh sample. In particular, microwave-dried samples were recorded as having the highest total phenolic content and the highest antioxidant capacity. To explain the drying kinetics of the date slices, nine thin-layer drying models were also attempted. Based on statistical tests, the model developed by Midilli et al. model was found to be the best model for convective and microwave drying, but the Two Term model was the best for freeze drying. This study shows that microwave drying can produce high quality date slices with the additional advantage of reduced drying times compared to convective and freeze drying. <![CDATA[Effect of black cumin oil (<em>Nigella sativa</em> L.) on fresh fish (<em>Barbus grypus</em>) fillets during storage at 2 ± 1 °C]]> Abstract It is important that the methods and materials used for to lengthen the shelf-life of food are simple, inexpensive and safe. For these reasons, herbal additives like cumin oil (Nigella sativa L.) have been preferred recently. Thus, the present study focuses on the influence of black cumin oil on chemical, microbiological and sensory quality of fish (Barbus grypus) fillets during storage at 2 ± 1 °C. Acceptability scores for sensory quality of all described treatment groups decreased with storage time. Defined limits for mesophilic bacteria and Total volatile basic nitrogen (TVB-N) were reached after 21st days for the control group, after 24th days for with 0.2% black cumin oil treated group and after 28th days for with 0.4% and 0.6% black cumin oil treated groups. No difference was found among groups during storage in terms of defined thiobarbituric acid (TBA) values. Consequently, it was found that black cumin oil treated groups had longer shelf-life and higher sensory quality than the untreated control group. <![CDATA[Optimization of culture medium for production of melanin by <em>Auricularia auricula</em>]]> Abstract Melanin is a natural high molecular weight pigment with the huge application value and development potential in food industry. In the present study, medium composition for melanin production by fungus Auricularia auricula was investigated. Wheat bran extract, l-tyrosine, and CuSO4 were determined to optimize medium composition by response surface methodology with Box–Behnken design. Results indicated that the optimal medium composition was 26.80% (v/v) wheat bran extract, 1.59 g/L l-tyrosine, and 0.11 g/L CuSO4, and the maximum melanin yield was 519.54 mg/L. Melanin production through A. auricula fermentation avoided expensive enzymatic or complicated chemical methods for melanin extraction from tissues of plant or animal, which had the huge application value and development potential for efficient production of melanin.