scholarly journals Stability of Vitamins B1, B2, B6 and E in a Fortified Military Freeze-Dried Meal During Extended Storage

Foods ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 39
Author(s):  
Ross Coad ◽  
Lan Bui

Australian military ration packs contain a variety of processed foods, including some that are fortified with vitamins. In this study, freeze-dried meals, a key component of lightweight patrol ration packs, were fortified at the time of packing by direct addition of a vitamin premix containing vitamins B1, B2, B6 and E. Fortification was at three levels: 50%, 100% and 200% of the recommended vitamin content for military ration packs. Vitamin stability was determined following storage at temperatures of 1 °C, 30 °C and 40 °C for up to 24 months. HPLC methods were used to measure vitamin content; water activity and colour were also determined. Mean 24-month retention rates across all temperatures and fortification levels were 94%, 97%, 86% and 77% for vitamins B1, B2, B6 and E, respectively. Water activity increased with storage temperature, whereas colour changes due to fortification and storage temperature were at the threshold of visual detection. Fortification of freeze-dried meals would be an effective means of improving the quality of light weight military ration packs by addressing shortfalls in vitamin levels.

1964 ◽  
Vol 36 (1) ◽  
pp. 161-180
Author(s):  
Taina Kuusi

Experiments have been made in the development of various new black-currant products, such as cloudy juice, juice concentrate and various freeze-dried preparations, along with a study of the effect of these different methods of preparation on the initial quality and storage properties. The quality was assessed from the stability of ascorbic acid and colour, the aroma number, and organoleptic evaluation. Storage lasted up to 8 months. It was established that the cloudiness exercised a slight protective effect on ascorbic acid. However, the instability of the cloud meant that the appearance of the cloudy juice was less attractive than that of the clear juice. No well-founded advantage of the cloudy juice could be demonstrated. Concentration proved less suitable, as there occurred harmful changes in ascorbic acid, colour and organoleptic properties. The freezing-drying method was excellent with respect to ascorbic acid and colour. In contrast, considerable losses in aroma occurred, with consequent weakening of the organoleptic properties. This method would be of advantage only in combination with aroma recovery, and solution of the financial problems involved. The results are discussed in the light of relevant literature.


Author(s):  
Huynh Nguyen Duy Bao ◽  
Sigurjón Arason ◽  
Kristín Anna Þórarinsdóttir

The influence of different cooling techniques (dry ice/ice packs) and storage temperature (-2°C/3°C) to prolong the shelf life of Arctic charr (Salvelinus alpinus) fillets were evaluated by sensory analysis, physical methods, chemical and microbial analysis. The effects of storage temperature were stronger than of different cooling agents. Superchilling (-2°C) of fillets packed with dry ice resulted in 6 days extension of shelf life compared to chilling (3°C). The use of dry ice parallel to superchilling prolonged shelf life for 1 day compared to fillets stored with ice packs. No negative effects on quality of the fillets where detected that could be linked to cell destruction caused by partial freezing or to sour taste, caused by absorption of CO2 gas in fish flesh.


2016 ◽  
Vol 79 (1) ◽  
pp. 148-152 ◽  
Author(s):  
TIAN DING ◽  
YAN-YAN YU ◽  
CHENG-AN HWANG ◽  
QING-LI DONG ◽  
SHI-GUO CHEN ◽  
...  

ABSTRACT The objectives of this study were to develop a probability model of Staphylococcus aureus enterotoxin A (SEA) production as affected by water activity (aw), pH, and temperature in broth and assess its applicability for milk. The probability of SEA production was assessed in tryptic soy broth using 24 combinations of aw (0.86 to 0.99), pH (5.0 to 7.0), and storage temperature (10 to 30°C). The observed probabilities were fitted with a logistic regression to develop a probability model. The model had a concordant value of 97.5% and concordant index of 0.98, indicating that the model satisfactorily describes the probability of SEA production. The model showed that aw, pH, and temperature were significant factors affecting the probability of toxin production. The model predictions were in good agreement with the observed values obtained from milk. The model may help manufacturers in selecting product pH and aw and storage temperatures to prevent SEA production.


LWT ◽  
2020 ◽  
Vol 121 ◽  
pp. 108926 ◽  
Author(s):  
Supaporn Klaykruayat ◽  
Busarakorn Mahayothee ◽  
Pramote Khuwijitjaru ◽  
Marcus Nagle ◽  
Joachim Müller

1948 ◽  
Vol 26f (3) ◽  
pp. 160-167
Author(s):  
D. MacDougall

Irish moss (Chondrus crispus) from Canada's east coast was used to study possible improvements in the production and storage of gelose. The optimum pH for the extraction of gelose from Irish moss was between 6 and 7. Fine leaf particles, which prevent rapid filtration, were readily removed by supercentrifuging. Comparison of drum drying and drying from the frozen state showed that the former caused a marked lowering of viscosity but had little effect on suspending power or jelly strength. The logarithm of the viscosity determined by means of a MacMichael viscosimeter was related directly to the concentration; therefore, viscosity measurements can be corrected for the moisture content of the samples. The effect of storage temperature on deterioration was greater than the effect of relative humidity. Samples stored at 0° and 40° F. for 12 weeks showed no significant changes in viscosity or suspending power, whereas those stored at 80° and 120° F. deteriorated very rapidly. Material was vacuum ice-dried to 2% moisture without damage but the quality decreased when the extracts were stored at high temperatures.


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