Psychrotrophic Counts (psychrotrophic + count)

Distribution by Scientific Domains


Selected Abstracts


Retail Shelf-Life of Pork Dipped in Organic Acid before Modified Atmosphere or Vacuum Packaging

JOURNAL OF FOOD SCIENCE, Issue 8 2005
Nai-Yun Huang
ABSTRACT Modified atmosphere packaging (MAP) is increasingly popular for meat, but raw, chilled pork in vacuum or anoxic environments has a purple color. The retail shelf-life of pork chops dipped in 500 ppm ascorbic acid, 250 ppm citric acid, or no acid dip and stored at 1 °C before simulated retail display in MAP with gas exchange or air-permeable packaging after vacuum pouch storage was determined. The 80% N2:20% CO2 in MAP was exchanged with 80% O2:20% CO2, and chops were removed from vacuum packages and overwrapped with permeable film (VP-PVC) on the 7th day before simulated retail display at 4 °C. Shelf-life traits were determined at 1, 7, 8, 10, 12, and 14 d postpackaging. The pH values changed with time, but returned to post-dipped, prepackaged levels at the end of simulated retail storage. Weight loss of chops increased (P < 0.05) in VP-PVC compared with MAP. The a* values increased (P < 0.05) and L* and b* values decreased during simulated retail display, with higher L*, a*, and b* color values for chops in MAP than VP-PVC. Log numbers of psychrotrophic microorganisms were higher (P < 0.05) on VP-PVC samples than for chops in MAP on days 12 and 14. Psychrotrophic counts on ascorbic acid-treated samples were decreased compared with citric acid or no dipping on pork during simulated retail display. Pork chops in MAP with gas exchange had lighter and redder color, increased weight retention, decreased psychrotrophic counts, and increased lipid oxidation compared with conventional vacuum and overwrap packaging systems. [source]


ASSESSMENT OF A WASH TREATMENT WITH WARM CHLORINATED WATER TO EXTEND THE SHELF,LIFE OF READY,TO,USE LETTUCE

JOURNAL OF FOOD QUALITY, Issue 3 2003
J.A. ODUMERU
There was a significant difference in psychrotrophic counts (P<0.0001) of warm chlorine (100 ppm) washed lettuce at 47 ± 2C for 30 s, 60 s, and 180 s exposure from days 1 to 10 of storage at 4C compared with cold chlorine (100 ppm) washed lettuce at 4 ± 1C for 30 s. There were no significant differences in psychrotrophic counts between wash treatments of 30 s and 60 s during 17 days storage (P < 0.05). The EN detected initially high levels of volatiles in this group compared with cold treatment. Lettuce samples treated with cold or warm chlorine wash water showed no differences in the presence/absence or levels of Listeria monocytogenes. The warm chlorine washed lettuce samples were rated acceptable upon sensory evaluation up to day 14. [source]


SENSORY ANALYSIS AND STORAGE STABILITY OF FLAVORED SOYBEAN SPREADS PRODUCED FROM HOT-GROUND SOYMILK,

JOURNAL OF FOOD QUALITY, Issue 2 2002
K.A. KHATIB
Flavored and unflavored soybean spreads were produced from a soybean variety low in beany off-flavors. The stability of the spreads was evaluated by chemical, physical, and microbiological tests over 35 days at 4C and 50% RH. Descriptive, focus group and consumer acceptance analyses were also conducted. Spreads were rated for degrees of beany flavor, aroma, and aftertaste. Total plate and psychrotrophic counts increased during storage, but no syneresis nor coliforms were detected over the storage period for either flavored or unflavored spreads. No significant treatment by day interactions were noted among pH, moisture content, water activity, lightness, and saturation index of spreads. Flavored spreads scored 6.2 on a 9-point hedonic scale and were more accepted by consumers than unflavored spreads. Shelf-life of flavored and unflavored soybean spreads was estimated to be 28 days at 4C. [source]


Retail Shelf-Life of Pork Dipped in Organic Acid before Modified Atmosphere or Vacuum Packaging

JOURNAL OF FOOD SCIENCE, Issue 8 2005
Nai-Yun Huang
ABSTRACT Modified atmosphere packaging (MAP) is increasingly popular for meat, but raw, chilled pork in vacuum or anoxic environments has a purple color. The retail shelf-life of pork chops dipped in 500 ppm ascorbic acid, 250 ppm citric acid, or no acid dip and stored at 1 °C before simulated retail display in MAP with gas exchange or air-permeable packaging after vacuum pouch storage was determined. The 80% N2:20% CO2 in MAP was exchanged with 80% O2:20% CO2, and chops were removed from vacuum packages and overwrapped with permeable film (VP-PVC) on the 7th day before simulated retail display at 4 °C. Shelf-life traits were determined at 1, 7, 8, 10, 12, and 14 d postpackaging. The pH values changed with time, but returned to post-dipped, prepackaged levels at the end of simulated retail storage. Weight loss of chops increased (P < 0.05) in VP-PVC compared with MAP. The a* values increased (P < 0.05) and L* and b* values decreased during simulated retail display, with higher L*, a*, and b* color values for chops in MAP than VP-PVC. Log numbers of psychrotrophic microorganisms were higher (P < 0.05) on VP-PVC samples than for chops in MAP on days 12 and 14. Psychrotrophic counts on ascorbic acid-treated samples were decreased compared with citric acid or no dipping on pork during simulated retail display. Pork chops in MAP with gas exchange had lighter and redder color, increased weight retention, decreased psychrotrophic counts, and increased lipid oxidation compared with conventional vacuum and overwrap packaging systems. [source]