葛根解酒含片的开发研制

概述了葛根的保健功效及其开发价值,研究以葛根提取物和茶多酚为主要原料的解酒含片的配方和生产工艺,通过口感优化试验和正交试验,确定含片的最佳配方。     

甘蔗渣纤维表面Zeta电位变化特性及其对酶水解效果的影响

将纤维素原料降解为可发酵糖是木质纤维素生物质生物转化乙醇过程中的重要环节,通过对原料的预处理可以提高纤维素酶的催化效率.本文通过改变甘蔗渣纤维的尺寸、添加多聚磷酸盐等方法,发现均能改变蔗渣纤维的表面Zeta电位.初步研究了其Zeta电位变化规律及Zeta电位的变化对纤维素酶水解效果的影响,并对Zeta电位的变化影响纤维...     

Photodegradation of Aflatoxin B<Subscript>1</Subscript> in peanut oil

A photodegradation study of aflatoxin B₁ (AFB₁) in peanut oil was performed under UV irradiation at different AFB₁ initial concentrations and UV irradiation intensities. The UV intensity and the irradiation duration on the AFB₁ photodegradation ratio is more effective, when compared with AFB₁ initial concentration, and AFB₁ with initial concentration of 2 mg/kg can be degraded thoroughly within 30 min under the intensity of 800 μw/cm². The photodegradation of AFB₁ between the selected ranges of concentrations was proved to follow first-order reaction kinetics well (R ² ≥ 0.99). The Ames test, employing Salmonella typhimurium tester strains TA98 and TA100, was employed to evaluate the residual toxicity of the AFB₁ subproducts in peanut oil, and the results indicated that the mutagenic activity of UV-treated samples (800 μw/cm² × 30 min) was completely lost compared with that of untreated samples, providing clues to the assessment of safety issues of UV method applied in AFB₁ decontamination.     

Rapid physicochemical characterization of innovative fucoidan/fructan powders by ATR–FTIR

Functional food has been highly demanded lately because of its benefits in counteracting diseases. Fucoidan and agave fructan are ingredients that enhance the growth of beneficial bacteria in the gut (prebiotics). This mixture has great potential to develop innovative products but it has never been explored before. Because of fucoidan is more expensive than agave fructan, the innovative proposed mixture is vulnerable to adulteration. This research was aimed to assess the accuracy of Fourier transform infrared spectroscopy with attenuated total reflectance (ATR–FTIR) coupled with chemometrics to identify and predict concentration of both polysaccharides in powder mixtures (0–100%). Absorption bands at 1240–1255 and 836–840 cm^?1 were attributed to fucoidan and a strong peak at ~ 936 cm^?1 confirmed the fructan presence. Peak areas were best fitted into linear models (\({\text{R}}_{\text{adj}}^{2}\) ≥ 0.92, RMSE ≤ 3.54%). This achievement may be useful to certificate ingredients contained in fucoidan–fructan mixtures, preventing adulteration.     

Optimization of ultrasonic-assisted extraction of phenolic compounds from <Emphasis Type="Italic">Justicia spicigera</Emphasis> leaves

A Box–Behnken design (Extraction-time, pulse-cycle, sonication-amplitude) was employed to extract phenolic compounds from Justicia spicigera leaves by ultrasonic-assisted extraction. The muicle leaves extracts were analyzed measuring total phenolic compounds and antioxidant capacity. According to response surface methodology the optimal conditions of ultrasonic-assisted extraction to obtain the highest soluble phenolic content were 2 min (extraction time) for 0.7 s (pulse cycle) at 55% of sonication amplitude. Under these optimal conditions, the total phenolic content was higher when was used ultrasonic-assisted extraction (54.02 mg/g) than stirring (46.46 mg/g) and thermal decoction (47.76 mg/g); however, the antioxidant capacity from J. spicigera extracts did not increase by ultrasonic-assisted extraction. The extracts or aqueous infusions from J. spicigera leaves are used for therapeutic proposes, therefore the ultrasonic-assisted extraction is a useful technology to improve the extraction of phytochemicals from J. spicigera leaves.     

Characterization of aromatic compounds and biological activities of essential oils from Tunisian aromatic plants

The aromatic compounds and biological activities of essential oils from six Tunisian aromatic plants including Artemisia herba-alba, Rosmarinus officinalis, Thymus capitatus, Mentha piperita, Ocimum basilicum and Artemisia absinthium were investigated. Hydro-distillation was used to extract essential oil from these plants. The identification of compounds from essential oils was performed using GC–MS analysis. Camphor (28.47%) was the major compound of A. absinthium essential oil. High contents of verbenone (20.99%) and camphor (19.72%) were found in R. officinalis. In the case of T. capitatus, carvacrol (81.09%), gamma terpinene (6.61%) and caryophyllene (4.87%) were identified as the major compounds. While eugenol (24.69%), linalool (18.00%) were characteristic compounds of O. basilicum essential oil, camphor (39.10%) and farnesol (14.25%) together with bornyl acetate (12.31%) were the main constituents of A. absinthium. These oils were also subjected to a screening for their antioxidant activity and essential oil from A. absinthium showed a greater antioxidant activity (IC₅₀?=?0.0063 mg/mL) compared to the standard Vitamin E (IC₅₀?=?0.019 mg/mL). The antibacterial activities of the oils against seven pathogenic strains, Pseudomonas aeruginosa, Bacillus cereus, Salmonella, Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, Enterococcus faecalis and Micrococcus luteus, were tested. The highest and broadest activity was shown by M. piperita; however, Ocimum basilicum was inactive against all strains. Essential oils were also evaluated for antidiabetic and anti-acetylcholinesterase activities. The IC₅₀ values of A. herba-alba and O. basilicum against α-amylase were respectively 17.76 and 16.32 µg/mL suggesting a powerful anti-diabetic effect comparable to that of acarbose (IC₅₀?=?14.88 µg/mL). R. officinalis, M. piperita and A. absinthium exhibited an interesting acetylcholinesterase inhibition with IC₅₀ equal to 22, 24 and 58 µg/mL respectively.     

Rosemary (<Emphasis Type="Italic">Rosmarinus officinalis</Emphasis>) oil: composition and functionality of the cold-pressed extract

The aim of this work was to investigate cold-pressed rosemary oil (RO) for its lipid classes, subclasses, fatty acid composition, tocochromanols and total phenolics amount. Antiradical activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH^?) and galvinoxyl radicals, antioxidant activity, as measured by the Rancimat test, as well as antimicrobial activity against food-borne bacteria, and dermatophytic fungi of RO were evaluated. In RO, the amount of neutral lipids was highest (ca. 86%), followed by phospholipids (0.92%) and glycolipids (0.88%). The percentages of monounsaturated, polyunsaturated, and saturated fatty acids were 41.7, 42.3, and 15.8%, respectively. Linoleic acid (41.7%) and oleic acid (41.2%) were the major fatty acids while linolenic acid accounted for 1.3% of total fatty acids. The following tocochromanols were detected: α-, β-, γ- and δ-tocopherols, which accounted for 291, 22, 1145, and 41 mg/100 g oil, respectively, as well as α-, β-, γ- and δ-tocotrienols, which accounted for 18, 12, 29, and 158 mg/100 g oil, respectively. RO also contained high levels of phenolic compounds (7.2 mg GAE/g). After 60 min of reaction with free radicals, 67% of DPPH^? and 55% of galvinoxyl radicals were quenched by RO. Rancimat test showed that blending RO with sunflower oil increased the induction period (IP) for blends. The IP of the RO: sunflower oil blend (1:9, v/v) was 390 min, and RO: sunflower oil blend (2:8, v/v) was longer (540 min). RO exhibited high antimicrobial potential against food-borne pathogenic bacteria (E. coli, S. enteritidis, and L. monocytogenes) and high antifungal potential against dermatophyte fungi (T. mentagrophytes, and T. rubrum). RO had unique high level of γ-tocopherol, which is a scavenger of reactive nitrogen species making it a promising material in the food, cosmetic and pharmaceutical applications.     

Bioactive properties of Kilka (<Emphasis Type="Italic">Clupeonella cultriventris caspi</Emphasis>) fish protein hydrolysates

Whole common Kilka fish was hydrolyzed separately using four commercial enzymes, Alcalase, Neutrase, Protamex at 50 °C and Pepsin at 37 °C for 30, 60 and 90 min. Degree of hydrolysis, angiotensin-I-converting enzyme (ACE) inhibitory activity and antimicrobial activity of each hydrolysate against Gram-negative (Escherichia coli, Salmonella enteritidis) and Gram-positive (Staphylococcus aureus, Listeria innocua) bacteria were studied. Results showed that the degree of hydrolysis for all enzymes was in the range of 2.63–3.36%. Electrophoresis profiles of the Kilka protein hydrolysates showed that most of produced peptides were in the range of 30 D but Alcalase and Neutrase had a better performance in the production of low molecular weight peptides in the range of 10 D. This led to increase the antimicrobial activity against the examined bacteria at the concentration of 200 µg/mL peptide solution. The Neutrase enzyme produced hydrolysate with the highest ACE inhibitory activity (53%?±?1.8 at 500 µg/mL). Antimicrobial activity of Kilka protein hydrolysates using Protamex and Pepsin was lower than the others due to lack of considerable amount of small peptides. The current research has demonstrated that the peptides derived from the enzymatic hydrolysis of Kilka fish protein in optimum conditions are capable of being converted to antimicrobial and antihypertensive agents to be used in functional foods.     

Impact of Temperature Cycling and Isothermal Storage on the Quality of Acidic and Neutral Shelf-Stable Dairy Desserts Packaged in Flexible Pouches

The aims of the present study were, first, to identify the quality changes occurring in sterilized vanilla and strawberry pudding during storage at 20 °C; second, to understand the effect of storage temperature on aging; and, third, to determine if temperature could be used as an accelerating factor for shelf life or stability studies. Shelf-stable pudding was produced industrially and packaged in flexible pouches. Different ingredients were used to produce strawberry and vanilla pudding, and the resulting pH was 4.1 and 6.5, respectively. Pudding pouches were kept for 7 days at 20 °C and stored for up to 112 days at ??18, 4, 20, and 30 °C, or cycled repeatedly between ??18 and 20 °C, 4 and 20 °C, and 30 and 20 °C with a frequency of two cycles per week. Color, pH, apparent viscosity, flow behavior, and fluorescence spectra measurements were conducted up to 112 days of storage. The most relevant indicators to monitor quality changes in vanilla pudding were η, pH, b*, and tryptophan emission spectra, and in strawberry pudding, a*, b*, and riboflavin, tryptophan, and vitamin A emission spectra. Indeed, the temperature of 30 °C was identified as the most suitable accelerating factor for accelerated aging tests regarding changes in pH, color, riboflavin, and tryptophan fluorescence spectra of pudding, while cycles of 4/20 °C and isothermal storage at 4 °C were the most appropriate tests to accelerate changes in apparent viscosity of pudding.     

Clarification of <Emphasis Type="Italic">Jerusalem Artichoke</Emphasis> Extract Using Ultra-filtration: Effect of Membrane Pore Size and Operation Conditions

Jerusalem artichoke is an important plant for industrial inulin production. Jerusalem artichoke extract was clarified by ultra-filtration. Tests were performed to investigate effects of membrane pore size and operation conditions (trans-membrane pressure and rotation speed) on filtration kinetics and membrane-fouling mechanism. Membrane fouling was proved the main filtration resistance for a 20-kDa membrane, while concentration polarization-induced resistance was dominant for 30-, 50-, and 100-kDa membranes. Despite their similar filtration behavior, the 50-kDa membrane, compared to the 100-kDa membrane, led to less protein content (impurity) in the filtrate. Studies with the rotation speed varied from 0 to 1600 rpm and trans-membrane pressure from 0.2 to 0.4 MPa demonstrated that stirring was essential for elimination of membrane fouling. Competition of driving force and fouling was justified when trans-membrane pressure increased from 0.3 to 0.4 MPa. Filtrate analysis including protein removal, turbidity, and inulin purity revealed that ultra-filtration using the 50-kDa membrane with a trans-membrane pressure of 0.3 MPa and a rotation speed of 800 rpm was able to clarify the Jerusalem artichoke extract, removing 99% protein, and obtain a filtrate with inulin purity of 98%.