scholarly journals Flavor and Other Quality Factors of Enzyme-peeled Oranges Treated with Citric Acid

HortScience ◽  
2007 ◽  
Vol 42 (7) ◽  
pp. 1644-1650 ◽  
Author(s):  
Simona Pinnavaia ◽  
Emilio Senesi ◽  
Anne Plotto ◽  
Jan A. Narciso ◽  
Elizabeth A. Baldwin
Keyword(s):  
Citric Acid ◽  
Bacterial Growth ◽  
Titratable Acidity ◽  
Taste Panel ◽  
Enzyme Treatment ◽  
Quality Factors ◽  
Microbial Counts ◽  
Aroma Volatiles ◽  
Colony Forming Units ◽  
Methyl Butanoate

Oranges can be satisfactorily processed for fresh slices using a process of enzyme infiltration under vacuum. Scored ‘Valencia’ and ‘Hamlin’ oranges were placed under 90 kPa vacuum in water, 1% citric acid (CA), or 1000 ppm pectinase (Ultrazym) at 30 °C for 2 min followed by 30 min incubation in air. After peeling, fruit were washed, cut, and all but CA-infused slices were dipped in water or 1% CA for 2 min. Drained slices were placed in sealed 454-mL deli containers and stored at 5 °C for up to 21 days. All ‘Valencia’ slices had microbial counts less than 1.0 log cfu·g−1 (cfu = colony-forming units) after 7 days storage, and slices from CA-infused fruit had less than 1.0 log cfu·g−1 after 21 days storage. For ‘Hamlin’, CA dips controlled bacterial growth on slices from water-infused oranges, except at 14 days. Enzyme-infused oranges resulted in slices with lower counts for both cultivars. CA-treated sliced (post enzyme treatment or by infusion) oranges had higher titratable acidity initially (‘Hamlin’) and after 14 days (‘Valencia’). When presented to a taste panel, ‘Valencia’ slices from enzyme-peeled fruit were preferred for texture after 2 days and 8 days in storage. In contrast, slices from fruit infused with water or citric acid were least preferred, were firmer, and had thicker segment membranes. Appearance of enzyme-treated fruit was preferred for ‘Hamlin’ oranges. Enzyme treatments increased levels of aroma volatiles, methanol and methyl butanoate, in ‘Hamlin’ slices, but overall sensory flavor data were unaffected.

CHANGES IN THE THERMAL STABILITY AND ACIDIC CHARACTERISTICS OF HYDROXY-Al-MONTMORILLONITE COMPLEXES FORMED IN THE PRESENCE OF CITRIC ACID

1985 ◽  
Vol 65 (3) ◽  
pp. 519-522 ◽  
Author(s):  
TEE BOON GOH ◽  
P. M. HUANG
Keyword(s):  
Thermal Stability ◽  
Citric Acid ◽  
Organic Carbon ◽  
Organic Acid ◽  
Key Words ◽  
Titratable Acidity ◽  
Structural Water ◽  
Molar Ratios ◽  
Gradual Loss

The thermal stability and acidic characteristics of Al interlayered montmorillonite were affected by citric acid which was present during its formation. Perturbation to the formation of Al interlayers by citric acid resulted in more gradual loss of their structural water in the 430 °C to 520 °C region at initial citric acid/Al molar ratios of 0.1 and 0.5. The data clearly reveal that, besides hydroxy-Al polymers, hydroxy-Al-citrate complexes adsorbed on the surfaces of montmorillonite very substantially contribute to the total and third buffer range titratable acidity of the clay. Key words: Hydroxy-Al-citrate interlayers, smectite, organic acid, DTA, third buffer range, organic carbon

Microbiological Quality of Commercial Tofu

1984 ◽  
Vol 47 (3) ◽  
pp. 177-181 ◽  
Author(s):  
T. G. REHBERGER ◽  
L. A. WILSON ◽  
B. A. GLATZ
Keyword(s):  
Microbiological Quality ◽  
Plate Count ◽  
Microbial Counts ◽  
Colony Forming Units ◽  
Low Levels ◽  
Microbial Groups ◽  
Yeasts And Molds ◽  
Processing Techniques

A study was done to investigate the microbiological quality of commercial tofu available in local retail outlets. A sampling method was first developed to obtain accurate and representative microbial counts of individual pieces of tofu. Plate count determination of total aerobic organisms, psychrotrophs, coliforms, sporeformers, yeasts and molds, and staphylococci were made on 60 tofu samples (representing three lots each of four different brands) obtained within 24 h after delivery to the retail store. In addition, for two brands that provided manufacturer's pull dates, the same microbial counts were obtained for samples stored in the laboratory at 10°C until the pull date. Of the tofu sampled immediately after purchase, 83% of the lots tested had total counts greater than 106 colony-forming units (CFU)/g and psychrotrophic counts greater than 104 CFU/g. In addition, 67% of the lots tested had confirmed coliform counts greater than 103 CFU/g. Very low levels (less than 10 CFU/g) of all other microbial groups tested for were found in the majority of lots. Samples held until the manufacturer's pull date contained higher total and psychrotrophic counts but lower or stable counts of other organisms compared with samples tested immediately after purchase. To improve the microbiological quality of tofu, processors need to reduce initial loads by improving sanitation and processing techniques, and retailers should provide more consistent and colder refrigerated storage.

EFFECTS OF CASTRATION, SIRE AND HORMONE TREATMENTS ON THE QUALITY OF RIB ROASTS FROM HOLSTEIN-FRIESIAN MALES

1975 ◽  
Vol 55 (3) ◽  
pp. 287-290 ◽  
Author(s):  
R. J. FORREST
Keyword(s):  
Hormone Treatment ◽  
Fat Deposition ◽  
Taste Panel ◽  
Quality Factors ◽  
Treatment Groups ◽  
Holstein Friesian ◽  
Panel Evaluation

A total of 72 Holstein-Friesian males from 11 sire groups were reared from birth on a concentrate ration. At 136 kg, one-half of the calves were castrated (Burdizzo) and at 340 kg, one-half of the bulls and steers were implanted with hormones (200 mg progesterone plus 20 mg estradiol-17-β-benzoate). Following slaughter at 475 kg, the 9th–11th rib sections were removed from the left sides of the carcass and frozen. Later, the four treatment and 11 sire groups were compared by taste panel evaluation of these rib roasts. No significant differences in quality factors (tenderness, juiciness, and flavor) due to pre-slaughter hormone treatment were evident in rib roasts from either bulls or steers. Hormone treatment significantly decreased (P < 0.05) fat deposition in steers and tended to increase fat levels in bulls. Rib roasts from bulls were significantly less desirable than roasts from steers in both treatment groups, for all quality factors. Significant sire effects for all taste panel evaluations were also noted.

scholarly journals Evaluation of production conditions of tomato grafted with different tobacco rootstocks and determining nicotine content and quality of fruit

2020 ◽  
Vol 115 (2) ◽  
pp. 297
Author(s):  
Seda TUNÇAY ÇAĞATAY ◽  
Gülşah ÇALIK KOÇ ◽  
Fereshteh REZAEİ ◽  
Özlem DARCANSOY İŞERI ◽  
Feride İffet ŞAHIN ◽  
...  
Keyword(s):  
Fruit Size ◽  
Titratable Acidity ◽  
Solid Content ◽  
Soluble Solid Content ◽  
Quality Factors ◽  
Nicotine Content ◽  
Positive Effects ◽  
Tomato Yield ◽  
Significant Difference ◽  
Soluble Solid

<p>This study aimed to investigate the effects of grafting tomato on different tobacco rootstocks on quality factors and nicotine content. The commercial variety (Solanum lycopersicum ‘H2274’) (BIOTECH) of the tomato was used as the scion plant, and six different tobacco (Nicotiana tabacum L.) rootstocks were used: Taşova, Tekel, Muş, Samsun, Dişbudak, Hasankeyf cultivars. Cleft grafting method was used in all plants. Yield of non-grafted and grafted plants grown in open-field conditions was calculated, and there was a significant increase in yield in grafted tomatoes compared to non-grafted tomatoes. There was significantly increased lycopene and β-carotene levels (mg kg-1), especially in ‘Tekel’, ‘Taşova’, ‘Samsun’, and ‘Hasankeyf’ tobacco grafts. There was a statistically significant difference between grafted and non-grafted plants according to 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical retention capacities and total phenol (TP) values. Evaluation of quality determinants including pH values, titratable acidity values (citric acid %), soluble solid content (SSC)(oBrix) , fruit size ratios, showed that tomatoes grafted with ‘Muş’ tobacco rootstock were of higher quality. There was no significant difference between grafted and non-grafted plants according to nicotine analysis of the tobacco-grafted tomatoes, and due to acceptable ranges of nicotin level on tobacco grafted tomato plants were considered to be suitable for consumption. It could be concluded that grafting practices have significantly positive effects on tomato yield and quality.<br /><br /></p>

scholarly journals Compositional Changes during the Fruit Development of Two Peach Cultivars Differing in Juice Acidity

1998 ◽  
Vol 123 (5) ◽  
pp. 770-775 ◽  
Author(s):  
Annick Moing ◽  
Laurence Svanella ◽  
Dominique Rolin ◽  
Monique Gaudillère ◽  
Jean-Pierre Gaudillère ◽  
...  
Keyword(s):  
Citric Acid ◽  
Fruit Development ◽  
Prunus Persica ◽  
Sucrose Concentration ◽  
Titratable Acidity ◽  
The Difference ◽  
Normal Acidity ◽  
Vacuolar Ph ◽  
C Nmr

Changes in metabolites were studied during the fruit development of two greenhouse grown peach [Prunus persica (L.) Batsch] cultivars with low acidity (`Jalousia') or normal acidity (`Fantasia'). Both cultivars had the same sucrose concentration in fruit mesocarp at maturity. In the fruit juice, pH was higher and titratable acidity was lower for `Jalousia' than for `Fantasia' from 80 days after bloom to maturity. At four different times during fruit development, in vivo 13C NMR spectroscopy was used to measure the vacuolar pH of fruit mesocarp. At 55 days after bloom, the vacuolar pH of fruit mesocarp was not significantly different between `Jalousia' and `Fantasia', whereas the juice pH was different between cultivars. The three major organic acids in fruit mesocarp were malic, citric, and quinic acids for both cultivars. Citric acid concentrations were similar in both cultivars until ≈85 days after bloom and then became significantly higher in `Fantasia'. A significantly higher concentration in malic acid in `Fantasia' than in `Jalousia' was observed from the end of the first growth phase to maturity. At maturity, `Fantasia' fruit had two and five times more malic and citric acid, respectively, than `Jalousia' fruit. The differences observed between `Jalousia' and `Fantasia' fruit for malic and citric acid concentrations accounted for the difference in titratable acidity. The differences in acid concentration appeared during the plateau between the two rapid growth phases of the fruit, i.e., far before the onset of maturation. The three major amino acids were asparagine, glutamic acid, and proline for both cultivars. Their concentration followed similar patterns in acid and low-acid fruit.

scholarly journals Potential of Postharvest Coatings to Maintain Freshness of Red-Fleshed Pitaya (Hylocereus costaricensis)

Agriculture ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 892
Author(s):  
Nur Azlin Razali ◽  
Steven A. Sargent ◽  
Charles A. Sims ◽  
Jeffrey K. Brecht ◽  
Adrian D. Berry ◽  
...  
Keyword(s):  
Weight Loss ◽  
Tap Water ◽  
Titratable Acidity ◽  
Quality Parameters ◽  
The Other ◽  
Soluble Solids ◽  
Postharvest Quality ◽  
Quality Factors ◽  
Climacteric Fruit

Pitaya is a non-climacteric fruit that has white or red flesh with numerous small, black seeds. It has a high moisture content; however, water loss during handling and storage negatively affects the fresh weight, firmness and appearance of the fruit, decreasing market value. Application of compatible postharvest coatings has been shown to benefit postharvest quality of many crops. The objective of this study was to evaluate the effect of two commercial coatings on weight loss and quality of pitaya during storage. Pitaya fruit were commercially harvested and sorted for uniformity of size and freedom from defects. Fruit were briefly immersed in either a vegetable oil-based coating (VOC; Sta-Fresh® 2981) or a carnauba-based coating (CC; Endura-Fresh™ 6100) according to manufacturer’s recommendations. Fruit immersed in tap water served as a control. Fruit were fan-dried at room temperature for 20 min, then stored at 7 °C with 85% relative humidity (RH) and evaluated for selected physical quality parameters each 5 days during 20 days. After each evaluation, fruit were peeled and frozen for later analysis of soluble solids content (SSC), total titratable acidity (TTA); on day 15 fresh samples were evaluated by an untrained consumer sensory panel. CC prevented exocarp shriveling for 15 days of storage, compared to uncoated pitaya (16.3% area affected); shriveling in VOC was intermediate and not significantly different from the other treatments. Mesocarp firmness remained constant throughout 15 days of storage regardless of treatment. Fruit exocarp h* angle increased slightly by day 20, becoming slightly less red, and there were no negative treatment effects for the other quality factors measured: SSC (11.33%), TTA (0.25%), weight loss (5.5%) or sensory evaluations (appearance, flavor, texture, firmness, and juiciness). After 20 days storage, appearance for fruit from all treatments was rated unacceptable due to development of anthracnose lesions. It was concluded that both CC and VOC maintained quality of pitaya for 15 days at 7 °C and 85% RH by delaying exocarp shriveling.

scholarly journals Anthocyanin Incorporated Dental Copolymer: Bacterial Growth Inhibition, Mechanical Properties, and Compound Release Rates and Stability by1H NMR

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Halyna Hrynash ◽  
Vinay Kumar Pilly ◽  
Alexandra Mankovskaia ◽  
Yaoyang Xiong ◽  
Getulio Nogueira Filho ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Growth Inhibition ◽  
Bacterial Growth ◽  
Testing Machine ◽  
Control Group ◽  
Uv Spectrophotometry ◽  
Release Rates ◽  
H Nmr ◽  
Colony Forming Units ◽  
Bacterial Growth Inhibition

Objective.To evaluate bacterial growth inhibition, mechanical properties, and compound release rate and stability of copolymers incorporated with anthocyanin (ACY;Vaccinium macrocarpon).Methods.Resin samples were prepared (Bis-GMA/TEGDMA at 70/30 mol%) and incorporated with 2 w/w% of either ACY or chlorhexidine (CHX), except for the control group. Samples were individually immersed in a bacterial culture (Streptococcus mutans) for 24 h. Cell viability (n=3) was assessed by counting the number of colony forming units on replica agar plates. Flexural strength (FS) and elastic modulus (E) were tested on a universal testing machine (n=8). Compound release and chemical stability were evaluated by UV spectrophotometry and1H NMR (n=3). Data were analyzed by one-way ANOVA and Tukey’s test (α= 0.05).Results.Both compounds inhibited S. mutans growth, with CHX being most effective (P<0.05). Control resin had the lowest FS and E values, followed by ACY and CHX, with statistical difference between control and CHX groups for both mechanical properties (P<0.05). The 24 h compound release rates were ACY: 1.33 μg/mL and CHX: 1.92 μg/mL.1H NMR spectra suggests that both compounds remained stable after being released in water.Conclusion.The present findings indicate that anthocyanins might be used as a natural antibacterial agent in resin based materials.

Povidone Iodine Sterilization of Contaminated CAPD-Exchange Spikes

1985 ◽  
Vol 5 (1) ◽  
pp. 24-26 ◽  
Author(s):  
Thomas A. Golper ◽  
David L. Sewell ◽  
Linda West ◽  
Marge Trinklein
Keyword(s):  
Bacterial Growth ◽  
Povidone Iodine ◽  
Bacterial Suspension ◽  
Limiting Factor ◽  
Group I ◽  
Dialysis Solution ◽  
Colony Forming Units ◽  
Physiologic Saline ◽  
Group 3 ◽  
Group 2

Thirty routine CAPD exchange spikes (Travenol) were dipped in a Staphylococcus aureus suspension and then divided into three equal groups. Group I (G1) spikes were advanced from the bacterial suspension to a povidone-iodine solution for a five-minute soak; Group 2 (G2) spikes were advanced into a sterile, non-bacteriostatic, physiologic saline solution for a five-minute soak. Then G1 and G2 spikes were attached in the usual sterile fashion to dialysis bags pretreated with tryptic soy broth to enhance bacterial growth. Group 3 (G3) spikes were advanced immediately to pretreated dialysate bags. Cultures of the dialysis solution were obtained immediately after the spikes were connected to the dialysis bags, 48 hours later, and at weekly intervals for three weeks. All 10 of the G3 bags connected to spikes without soaking grew greater than 10 colony forming units/mi of S. aureus by 48 hours. All 10 of the saline soaked G2 bags also demonstrated growth at 48 hours. Only one of the 10 Gl povidone-iodine soaked spike bags grew detectable colonies of bacteria at 48 hours. We conclude that a five-minute povidone-iodine soaking of spikes contaminated with S. aureus usually will prevent bacterial growth but is not a perfect solution to the problems of spike contamination. The frequent occurrence of peritonitis remains the limiting factor to the widespread acceptance of CAPD. Oreopoulos et al proposed that 36.5% of episodes of peritonitis are secondary to contaminations at the connection site during the a CAPD bag exchange (1). Although the exact frequency is unknown, we agree that the likelihood is high that contamination at the time of the exchange is a common mode of bacterial access to the peritoneal cavity. When we established our CAPD programs we instructed our patients to change the tubing if the spike became contaminated. Patients only rarely notified us of this necessity, despite our suspicion that known contamination was occurring. Two of us asked the Bulletin's editors if one could manage spike contamination simply by soaking the spike in povidone-iodine (2). Vas recommended that the tubing be changed because simple soaking would not deal with contamination inside the lumen (3). We decided to study this issue further because we believed that patients would not comply with this recommendation.

Effect of citric acid on the radiation resistance of Listeria monocytogenes and frankfurter quality factors

Meat Science ◽  
2003 ◽  
Vol 63 (3) ◽  
pp. 407-415 ◽  
Author(s):  
Christopher H Sommers ◽  
Xuetong Fan ◽  
A.Phillip Handel ◽  
Kimberly Baxendale Sokorai
Keyword(s):  
Listeria Monocytogenes ◽  
Citric Acid ◽  
Radiation Resistance ◽  
Quality Factors

scholarly journals Antimicrobial potential of ozone in an ultrasonic cleaning system against Staphylococcus aureus

2006 ◽  
Vol 17 (2) ◽  
pp. 134-138 ◽  
Author(s):  
Carlos Estrela ◽  
Cyntia R.A. Estrela ◽  
Daniel de Almeida Decurcio ◽  
Julio Almeida Silva ◽  
Lili Luschke Bammann
Keyword(s):  
Staphylococcus Aureus ◽  
Bacterial Growth ◽  
Culture Medium ◽  
Distilled Water ◽  
Ultrasonic Cleaning ◽  
Antimicrobial Potential ◽  
Cleaning System ◽  
Colony Forming Units ◽  
A Current ◽  
Made In

The aim of this study was to evaluate the antimicrobial potential of ozone applied to 3 different solutions in an ultrasonic cleaning system against Staphylococcus aureus. A total of 120 mL of S. aureus were mixed in 6 L of the experimental solutions (sterilie distilled water, vinegar and sterile distilled water + Endozime AWpluz) used in a ultrasonic cleaning system (UCS). Ozone was produced by an electric discharge through a current of oxygen and bubbling with flow rate at 7g/h ozone (1.2%) into the microbial suspensions. Ten mL of each experimental suspension were collected and 5 fold dilutions were made in 9 mL of BHI and incubated at 37°C for 48 h. Bacterial growth was evaluated by turbidity of the culture medium. At the same time, 1 mL of bacterial samples was collected and inoculated in BHIA plates. After incubation at 37°C for 48 h, the number of colony forming units (cfu) per mL on BHIA surface was counted. In dilution test in BHI tubes and in BHIA plates (cfu/mL), bacterial growth was not observed in any of the experimental solutions when ozone was added. Under the tested conditions, it may be concluded that the addition of ozone to a ultrasonic cleaning system containing different experimental solutions resulted in antibacterial activity against S. aureus.

Sign in / Sign up

Export Citation Format

Share Document