scholarly journals Effects of UV-C Irradiation and Thermal Processing on the Microbial and Physicochemical Properties of Agave tequilana Weber var. azul Extracts at Various pH Values

Processes ◽  
2020 ◽  
Vol 8 (7) ◽  
pp. 841
Author(s):  
Aracely Z. Santana-Jiménez ◽  
Armando Quintero-Ramos ◽  
Miguel Á. Sánchez-Madrigal ◽  
Carmen O. Meléndez-Pizarro ◽  
María del Cielo Valdez-Cárdenas ◽  
...  
Keyword(s):  
Physicochemical Properties ◽  
Sugar Content ◽  
Color Difference ◽  
Agave Tequilana ◽  
Total Polyphenols ◽  
Ph Values ◽  
Yeasts And Molds ◽  
Uv C ◽  
Total Color Difference ◽  
Microbiological Properties

The effects of UV-C irradiation (at doses of 8.16, 10.93, 16.17, and 33.29 mJ/cm2) on the physicochemical and microbiological properties of Agave tequilana Weber extracts at various pH values (4.5, 5.5, and 6.5) were evaluated. Thermal treatment (TT) was used as a control (85 °C for 30 s). Both processed (UV-C or TT) and unprocessed (UP) extracts were investigated. The UV-C dose and the pH significantly (p < 0.05) affected the inactivation of total coliforms (TC), total aerobic mesophiles (TAM), and yeasts and molds (YM). UV-C doses of 10.93 mJ/cm2 at pH 4.5 and 33.29 mJ/cm2 at any agave extract pH completely inactivated the native microbial load compared to TT. The total polyphenols (TP), antioxidant activity (AA), and sugar content did not change in the agave extracts at any dose, but the total flavonoid (TF) content decreased at doses > 16.17 mJ/cm2 at the evaluated pH values. Although the color of the agave extracts (L*, a*, and b*) was significantly affected, the total color difference (∆E) did not change after processing compared to the ∆E in the UP extracts. TT further reduced all the physicochemical properties of the agave extracts compared to UV-C processing. The results suggest that UV-C continuous flow technology can be used to stabilize agave extracts at doses of 10.93 mJ/cm2 and pH 4.5, while preserving their functional properties.

scholarly journals Physicochemical properties of extruded ready-to-eat snack from unripe plantain blends, pineapple by-products and stevia

Nova Scientia ◽  
2021 ◽  
Vol 13 (27) ◽  
Author(s):  
Betsabé Hernández-Santos ◽  
José Manuel Juárez-Barrientos ◽  
Juan Gabriel Torruco-Uco ◽  
Enrique Ramírez-Figueroa ◽  
Emmanuel de Jesús Ramírez-Rivera ◽  
...  
Keyword(s):  
Physicochemical Properties ◽  
Water Solubility ◽  
Color Difference ◽  
Screw Extruder ◽  
Compression Screw ◽  
Sensory Acceptance ◽  
Single Screw Extruder ◽  
Feed Moisture ◽  
By Products ◽  
Total Color Difference

The aim of this research was to evaluate the effect of extrusion temperature (ET 120 – 180 °C), feed moisture content (FMC 16 - 25 g/100 g), pineapple by-products proportion (PBP) (0 - 30 g/100 g) in the unripe plantain flour, and the stevia content (STC 0 - 5 g/100 g) on the physicochemical properties and sensory acceptance of ready-to-eat extruded snacks, through a central compound design, using a single-screw extruder with a compression screw ratio of 3:1. The results were analyzed by response surface. The increase in FMC, PBP and STC decreased (p < 0.05) the expansion index (EI). The increase in ET decreased (p < 0.05) the apparent density (AD), water absorption index (WAI), water solubility index (WSI) and total color difference (ΔE). The increase in FMC decreases EI, WAI, and increase AD and WSI (p < 0.05). The Increase in PBP decreased EI, WSI, and increase AD, hardness (H) and ΔE (p < 0.05). The increase in STC decreased (p < 0.05) EI, and increase AD and H. The treatments with greater general acceptability were those that contained 15 and 30 g/100 g of PBP and STC 2.5 g/100 g, and they were obtained at ET 150ºC and 20.5 g/100 g of FMC, without affecting the physicochemical properties.

scholarly journals Physicochemical properties, sensory attributes and consumer preference of soursop leather

2020 ◽  
Vol 73 (2) ◽  
pp. 9189-9199
Author(s):  
Rita M. Avila de Hernandez ◽  
María V. Mujica de Soto ◽  
Edwin A. Hernández Caraballo ◽  
Aracelis J. Giménez Machado ◽  
Marie T. González de Rangel ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Consumer Preference ◽  
Titratable Acidity ◽  
Color Difference ◽  
Soluble Solids ◽  
Total Polyphenols ◽  
Total Polyphenol ◽  
Browning Index ◽  
Hue Angle ◽  
Total Color Difference

A soursop leather was prepared, and its physicochemical and sensory properties were assessed. The preparation of the leather was carried out based on an experimental mix design. The combination of soursop pulp (79-100%), sugar (0-20%), and citric acid (0-1%) produced five treatments. The optimum mixture, viz., TII (80:20:0), and the midpoint mixture, viz., TV (89.5:10:0.5), were finally selected, using an acceptability test (taste and color) with an untrained panel. These two treatments were evaluated, recording the variation of total soluble solids (TSS), pH, titratable acidity, ascorbic acid, total polyphenols, and color (chroma, hue angle, browning index and total color difference) every 15 days over for a 45-day period. It was determined that it can be prepared from the soursop pulp, a leather with high acceptability (taste; color): TIV (8.68; 7.90) and TII (8.51; 7.72) on a 12-point scale. Significant changes in TSS, pH, titratable acidity, total polyphenols, and color (chroma, browning index, and total color difference) were observed during the 45 days of storage at room temperature. Both ascorbic acid and total polyphenol content make the soursop leather a product with potentially healthy characteristics.

scholarly journals Continuous Flow UV-C Irradiation Effects on the Physicochemical Properties of Aloe vera Gel and Pitaya (Stenocereus spp.) Blend

Foods ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 1068
Author(s):  
Carmen O. Meléndez-Pizarro ◽  
Arlet Calva-Quintana ◽  
José C. Espinoza-Hicks ◽  
Miguel Á. Sánchez-Madrigal ◽  
Armando Quintero-Ramos
Keyword(s):  
Physicochemical Properties ◽  
Continuous Flow ◽  
Sugar Content ◽  
Aloe Vera ◽  
Color Parameter ◽  
Irradiation Effects ◽  
Total Sugar Content ◽  
Aloe Vera Gel ◽  
Simple Sugar ◽  
Uv C

Physicochemical properties of a blend of 10% Aloe vera gel with 5% pitaya juice subjected to UV-C doses of 16.5, 27.7, and 40 mJ/cm2 were evaluated at pH 3.5 and 5.5. Unprocessed treatments were used as the control. The a* color parameter decreased and luminosity increased at pH 3.5. The decrease in the reddish color was consistent with the decrease in total betalains content and stabilized at pH 5.5. The NMR analyses of UV-C treatments showed changes in betalains signal patterns. Polyphenolics content was significantly reduced in the UV-C treatments at pH 5.5. UV-C processing decreased the antioxidant activity 1.25 times compared to unprocessed treatments. Total sugar content was reduced as the UV-C dose increased. Doses above 16.5 mJ/cm2 resulted in a higher simple sugar content at a pH 3.5. The UV-C continuous flow technology can be applied to stabilize betalains in Aloe vera–pitaya blends at a UV-C dose of 16.5 mJ/cm2 and pH 5.5.

scholarly journals Physicochemical properties of vacuum packaged snake fruits in the presence of olive leave extract

Food Research ◽  
2020 ◽  
Vol 4 (S1) ◽  
pp. 250-255
Author(s):  
A.N. Al-Baarri ◽  
F.P. Lestari ◽  
H.M. Wahda ◽  
Widayat ◽  
A.M. Legowo
Keyword(s):  
Physicochemical Properties ◽  
Room Temperature ◽  
Color Difference ◽  
Vacuum Packaging ◽  
Ambient Conditions ◽  
Olive Leaves ◽  
Color Changes ◽  
Fresh Cut ◽  
Total Dissolved Solid ◽  
Total Color Difference

This research was done to investigate the effectiveness of the presence of olive leaf extract in vacuum packaging in maintaining the physicochemical properties of fresh-cut snake fruit under ambient temperature. The snake fruits were vacuum packaged in the presence of 3% (v/w) olive leave extract (OLE) and stored in room temperature for 8 days of storage. The physicochemical properties including color changes, firmness, and total dissolved solid (TDS) were observed. The results indicated that addition olive leaves extract in vacuum packaging gave the best result by inhibiting color changes by declining in total color difference by 10.88, BI 5.08, absorbance 2.750 Ǻ declining in hardness by 14.61% and lowest TDS level. As an alternative method of storing fresh-cut snake fruit under ambient conditions, vacuum packaging containing olive leave extract can be used.

scholarly journals Correlating Capsaicinoid Levels and Physicochemical Proper-ties of Kimchi and Its Perceived Spiciness

Foods ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 86
Author(s):  
So-Ra Yoon ◽  
Yun-Mi Dang ◽  
Su-Yeon Kim ◽  
Su-Yeon You ◽  
Mina K. Kim ◽  
...  
Keyword(s):  
Correlation Analysis ◽  
Physicochemical Properties ◽  
Correlation Coefficient ◽  
Partial Correlation ◽  
Sugar Content ◽  
Amino Acid Content ◽  
Titratable Acidity ◽  
Free Sugar ◽  
Partial Correlation Analysis ◽  
The Relationship

Capsaicinoid content, among other factors, affects the perception of spiciness of commercial kimchi. Here, we investigated whether the physicochemical properties of kimchi affect the spicy taste of capsaicinoids perceived by the tasting. High-performance liquid chromatography (HPLC) was used to evaluate the capsaicinoid content (mg/kg) of thirteen types of commercial kimchi. The physicochemical properties such as pH, titratable acidity, salinity, free sugar content, and free amino acid content were evaluated, and the spicy strength grade was determined by selected panel to analyze the correlation between these properties. Panels were trained for 48 h prior to actual evaluation by panel leaders trained for over 1000 h according to the SpectrumTM method. Partial correlation analysis was performed to examine other candidate parameters that interfere with the sensory evaluation of spiciness and capsaicinoid content. To express the specific variance after eliminating the effects of other variables, partial correlations were used to estimate the relationships between two variables. We observed a strong correlation between spiciness intensity ratings and capsaicinoid content, with a Pearson’s correlation coefficient of 0.78 at p ≤ 0.001. However, other specific variables may have influenced the relationship between spiciness intensity and total capsaicinoid content. Partial correlation analysis indicated that the free sugar content most strongly affected the relationship between spiciness intensity and capsaicinoid content, showing the largest first-order partial correlation coefficient (rxy/z: 0.091, p ≤ 0.01).

scholarly journals Effect of holding period prior to storage on the chemical attributes of Starking Delicious apples during refrigerated storage

2012 ◽  
Vol 32 (2) ◽  
pp. 223-227
Author(s):  
Aynur Batkan ◽  
Akif Kundakçi ◽  
Bülent Ergönül
Keyword(s):  
Ascorbic Acid ◽  
Dry Matter ◽  
Sugar Content ◽  
Titratable Acidity ◽  
Quality Attributes ◽  
Reducing Sugar ◽  
Refrigerated Storage ◽  
Holding Period ◽  
Ph Values ◽  
Chemical Attributes

In this research, the effects of three different holding periods (6, 12 and 24 hours) prior to storage on the quality attributes of Starking Delicious apples were investigated during storage of 8 months at 0.5 ± 1.0 ºC. Changes in weight loss, flesh firmness, pH values, soluble dry matter amount, titratable acidity values, ascorbic acid contents, and total and reducing sugar content were determined. According to the results, the holding period showed statistically significant changes in the quality attributes of the apples (p < 0.05).

scholarly journals Quality stability and sensory attributes of apple juice processed by thermosonication, pulsed electric field and thermal processing

2016 ◽  
Vol 23 (3) ◽  
pp. 265-276 ◽  
Author(s):  
Alifdalino Sulaiman ◽  
Mohammed Farid ◽  
Filipa VM Silva
Keyword(s):  
Antioxidant Activity ◽  
Electric Field ◽  
Sensory Analysis ◽  
Thermal Processing ◽  
Apple Juice ◽  
Treatment Time ◽  
Pulsed Electric Field ◽  
Color Difference ◽  
Soluble Solids ◽  
Total Color Difference

Worldwide, apple juice is the second most popular juice, after orange juice. It is susceptible to enzymatic browning spoilage by polyphenoloxidase, an endogenous enzyme. In this study, Royal Gala apple juice was treated by thermosonication (TS: 1.3 W/mL, 58 ℃, 10 min), pulsed electric field (PEF: 24.8 kV/cm, 60 pulses, 169 µs treatment time, 53.8 ℃) and heat (75 ℃, 20 min) and stored at 3.0 ℃ and 20.0 ℃ for 30 days. A sensory analysis was carried out after processing. The polyphenoloxidase activity, antioxidant activity and total color difference of the apple juice were determined before and after processing and during storage. The sensory analysis revealed that thermosonication and pulsed electric field juices tasted differently from the thermally treated juice. Apart from the pulsed electric field apple juice stored at room temperature, the processed juice was stable during storage, since the pH and soluble solids remained constant and fermentation was not observed. Polyphenoloxidase did not reactivate during storage. Along storage, the juices’ antioxidant activity decreased and total color difference increased (up to 6.8). While the antioxidant activity increased from 86 to 103% with thermosonication and was retained after pulsed electric field, thermal processing reduced it to 67%. The processing increased the total color difference slightly. No differences in the total color difference of the juices processed by the three methods were registered after storage. Thermosonication and pulsed electric field could possibly be a better alternative to thermal preservation of apple juice, but refrigerated storage is recommended for pulsed electric field apple juice.

scholarly journals Pengaruh Lokasi Geografis dan Vegetasi terhadap Sifat Fisikokimia Madu dari Ciwidey dan Bogor

2020 ◽  
Vol 1 (2) ◽  
pp. 71
Author(s):  
Emanuela Rae Alodia ◽  
Anas Bunyamin ◽  
Efri Mardawati
Keyword(s):  
Physicochemical Properties ◽  
Water Content ◽  
Sugar Content ◽  
Geographical Location ◽  
B Value ◽  
Reducing Sugar ◽  
National Standard ◽  
Color Analysis ◽  
A Value ◽  
C Value

<p><em>Physicochemical properties are one of the parameters of honey quality that impacts the sales of honey as well as the economy condition of the society in Ciwidey and Bogor. The physicochemical properties of honey are significantly influenced by the origin of the honey, including its geographical location and vegetation. This study aims to determine the physicochemical properties between multiflora honey from Ciwidey and Bogor with different source of nectar where Ciwidey honey is dominated by calliandra nectar while Bogor honey is dominated by kapok nectar. Data were analyzed with descriptive and quantitative method using independent t test for data with normal distribution (water content and reducing sugar content). Data that were not normally distributed (color analysis and acidity value) were tested non-parametrically with the Mann Whitney-U. The results showed that Bogor honey has the better physicochemical properties and meets Indonesian National Standard (Standar Nasional Indonesia, SNI) 8664:2018, with a water content of 15.15% w/w, L* values of 35.26, a* value of 28.66, b* value of 59.46, c* value of 66.01, h* value of 64.27°, reducing sugar content of 78.78% and acidity value of 35.56 mL NaOH kg-1. Phytochemical screening showed positive results on alkaloid, flavonoid, phenol and tannin, and the results of GC-MS analysis showed three significant compounds which are hydroxymethylfurfural of 48.26%, levoglucosan of 13.58% and ammonium carbamate of 9.18%.</em></p>

Packaging of Beef Loin Steaks in 75% O2 Plus 25% CO2. II. Microbiological Properties

1981 ◽  
Vol 44 (12) ◽  
pp. 928-933 ◽  
Author(s):  
M. O. HANNA ◽  
C. VANDERZANT ◽  
G. C. SMITH ◽  
J. W. SAVELL
Keyword(s):  
Microbial Population ◽  
Microbial Flora ◽  
Refrigerated Storage ◽  
Ph Values ◽  
Acinetobacter Sp ◽  
Retail Conditions ◽  
Microbiological Properties

Numbers and types of bacteria were determined on steaks after refrigerated storage (1 ± 1 C) in 75% O2 plus 25% CO2 for 9 days in the dark plus display at 2 ± 2 C for 4 days under simulated retail conditions. Steaks were prepared from strip loins (IMPS #180) as received from the supplier (trial 1) and also from the same or similar loins that were vacuum-packaged at day 0 (trial 1) and then stored under refrigeration for 14 (trial 2) or 28 days (trial 3). Initially (day 0, trial 1), the microflora of steaks consisted primarily of Micrococcus and Moraxella-Acinetobacter sp. Following refrigerated storage in vacuum packages for either 14 or 28 days, Lactobacillus and Leuconostoc sp. became dominant. Refrigerated storage and display of steaks in 75%O2 plus 25% CO2 shifted the microbial population in favor of Leuconostoc sp. Initial log counts of steaks (day 0, trial 1) ranged from 0.88 to 2.02. Counts of steaks stored for 9 or 13 days in 75% O2 plus 25% CO2 nearly always exceeded 106 per cm2 when steaks were prepared from loins which had been stored in vacuum packages for either 14 or 28 days. The pH values of steaks prepared from loins which had been stored under refrigeration for 14 days were lower (0.27–0.56) than those of steaks prepared from comparable loins as they were received from the supplier (day 0, trial 1). Refrigerated storage of vacuum-packaged loins for an additional 14 days did not cause marked changes in pH of the steaks. No consistent differences in microbial flora were detected between green- and normal-pigmented areas of steaks prepared from vacuum-packaged loins which had been stored refrigerated for 14–28 days.

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