| 1. |
- Undeland, Ingrid, 1968, et al.
(författare)
-
Lipid oxidation in fillets of herring (Clupea harengus) during frozen storage. Influence of pre-freezing storage.
- 1999
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Ingår i: Journal of Agricultural and Food Chemistry. - : American Chemical Society (ACS). - 0021-8561 .- 1520-5118. ; 47:5, s. 2075-2081
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Tidskriftsartikel (refereegranskat)abstract
- Fillets of herring (Clupea harengus) were kept on ice for 0, 3, 6, and 9 days prior to storage at −18 °C for 0, 21, 42, 63, and 84 days. At each storage point, peroxide value (PV), absorbance at 268 nm (A268), fluorescent products (FP), α-tocopherol, glutathione peroxidase (GSH-px) activity, and ascorbic acid were measured. As shown by regression analyses, samples held for 6 days on ice formed oxidation products at the highest rate during frozen storage, followed by, for PV and FP, the 9-day samples. These data indicate that severe changes that negatively affect the oxidation process took place in the herring muscle between 3 and 6 days after catch. Both the initial antioxidant levels and the rate of antioxidant loss at −18 °C decreased with increased prefreezing holding time, the latter being most obvious for GSH-px activity and ascorbic acid. α-Tocopherol showed the largest losses and had disappeared entirely from the 6- and 9-day samples at the end of the frozen storage. Partial least-squares regression analysis of the data showed that ice storage had a greater effect than frozen storage on changes in PV, A268, FP, α-tocopherol, and ascorbic acid. For GSH-px activity, frozen storage had the greatest effect.
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| 2. |
- Undeland, Ingrid, 1968, et al.
(författare)
-
Lipid Oxidation in Fillets of Herring (Clupea harengus) during Ice Storage
- 1999
-
Ingår i: Journal of Agricultural and Food Chemistry. - : American Chemical Society (ACS). - 0021-8561 .- 1520-5118. ; 47:2, s. 524-532
-
Tidskriftsartikel (refereegranskat)abstract
- The influence of ice storage on lipid oxidation, odor, antioxidants, water-soluble catalysts, and microorganisms was investigated in fillets of herring (Clupea harengus) during 15 days. Based on linear regression analyses of the data, significant rises (p ≤ 0.05) in lipid oxidation products were seen after 2−3 days and in “rancid” odor after 2.5 days. Peroxide value (PV), fluorescent product (FP), and ascorbic acid analyses were the chemical measures most strongly correlated to “rancid” odor (r = 0.97). Antioxidants decreased in the following order: α-tocopherol > ascorbic acid > glutathione peroxidase (GSH-px); however, GSH-px correlated best to the development of lipid oxidation products (rmean = −0.96). The activity of aqueous pro-oxidants, which were enzymatic in nature to a great extent, had decreased by 75% at day 15. No significant increase in total bacteria was seen until after 7 days. There were major local differences in both composition and stability throughout the fillet. Oxidation proceeded most rapidly in the tissue right under the skin, probably explained by its high initial pro-oxidative activity.
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| 3. |
- Undeland, Ingrid, 1968, et al.
(författare)
-
Lipid Oxidation in Minced Herring (Clupea harengus) during Frozen Storage. Effect of Washing and Precooking
- 1998
-
Ingår i: Journal of Agricultural and Food Chemistry. - 0021-8561 .- 1520-5118. ; 46, s. 2319-2328
-
Tidskriftsartikel (refereegranskat)abstract
- A 23 factorial experimental design was used to investigate the effect of washing in combination with precooking on the oxidative stability of lipids in minced herring (Clupea harengus) at −18 °C. The following variables were studied: washing (no, yes), cooking time (38, 54 min), and cooking temperature (55, 100 °C).The responses monitored were peroxide value (PV), absorbance at 234 nm (A234), absorbance at 268 nm (A268), and lipid soluble fluorescent products (FP). A partial least-squares regression analysis (PLS) revealed that the best lipid stability was obtained at minimum cooking time and at lower temperature. On the basis of compositional analyses and in vitro experiments, this finding was proposed to be due to heat inactivation of catalytic enzymes, without simultaneous activation, for example, of hemoproteins. Washing reduced these benefits from precooking by removal of pro-oxidative enzymes and also through a reduction in the amount of antioxidants as well as a relative increase in phospholipids and free fatty acids in the fat.
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| 4. |
- Börjesson, Thomas S., et al.
(författare)
-
Off-odorous compounds produced by molds on oatmeal agar : Identification and relation to other growth characteristics
- 1993
-
Ingår i: Journal of Agricultural and Food Chemistry. - Washington : American Chemical Society (ACS). - 0021-8561 .- 1520-5118. ; 41:11, s. 2104-2111
-
Tidskriftsartikel (refereegranskat)abstract
- Ten Penicillium and Aspergillus species, four with a strong musty off-odor and six reference fungi without any characteristic odor, were cultivated on oatmeal agar for 5 days in cultivation vessels provided with an inlet and an outlet for air. Samples of volatile metabolites were collected on a porous polymer adsorbent attached to the outlet from day 2 through day 5 after inoculation. Adsorbed compounds were desorbed thermally and analyzed with GC/MS and a combined GC and sensory analysis, the GC sniff technique. Multivariate analysis of GC/MS and fungal odor data revealed strong associations between 6 of 65 volatile compounds and musty off-odor. The GC sniff technique showed that five of these, dimethyl disulfide, 1-octen-3-ol, 2-methylisoborneol, and two C11H18 compounds, had prominent off-odors. In addition, geosmin, 1-methoxy-3-methylbenzene, and methylphenol were produced in large amounts by some off-odorous fungi and contributed to their unpleasant odor. 3-Methylfuran, 2-methyl-1-propanol, and 3-methyl-1-butanol were much more commonly produced than the off-odorous compounds. Both odorous and other volatile metabolites could be detected after 2 days of fungal growth. The production of odorous metabolites was enhanced at the time of sporulation.
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| 5. |
- Petersson, Stina, et al.
(författare)
-
Growth of Penicillium roqueforti, P-carneum, and P-paneum during malfunctioning airtight storage of high-moisture grain cultivars
- 1999
-
Ingår i: Postharvest biology and technology. - : Elsevier. - 0925-5214 .- 1873-2356. ; 17:1, s. 47-54
-
Tidskriftsartikel (refereegranskat)abstract
- Penicillium roqueforti is an important spoilage fungus in high-moisture grain stored under airtight conditions where a malfunctioning storage system allows air leakage. It has recently been proposed that P. roqueforti be divided into three different species: P. roqueforti, P. carneum, and P. paneum (Boysen, M., Skouboe, P., Frisvad, J., Rossen, L., 1996. Reclassification of the Penicillium roqueforti group into three species on the basis of molecular genetic and biochemical profiles. Microbiology 142, 541-549). Differences in susceptibility to infection with the three mold species among winter wheat, spring wheat, rye, and barley during airtight storage of high-moisture grain were evaluated using a variety of grain cultivars. To simulate air leakage into such a storage system, grain (0.96 water activity) was inoculated, packed in glass tubes with a restricted air supply and incubated at 25 degrees C for 14 days. Molds and yeasts were quantified as colony forming units (CFU) on selective media. Generally, there was no difference in infection ability between P. roqueforti, P. carneum and P. paneum. All of them reached about 10(6) CFU/g in barley and winter wheat. However, rye appeared to be resistant to infection. A comparison of different barley and spring wheat cultivars revealed that P. roqueforti, P. carneum and P. paneum grew less vigorously on the malt cultivars Maud and Mentor and the spring wheat cv. Dragon than on other cultivars. In addition, batch-related differences in resistance to mold growth were found for spring wheat cv. Dragon.
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| 6. |
- Petersson, Stina, et al.
(författare)
-
Pichia anomala as a biocontrol agent during storage of high-moisture feed grain under airtight conditions
- 1999
-
Ingår i: Postharvest biology and technology. - : Elsevier. - 0925-5214 .- 1873-2356. ; 15:2, s. 175-184
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Tidskriftsartikel (refereegranskat)abstract
- Pichia anomala is antagonistic against a range of spoilage molds in vitro as well as against Penicillium roqueforti in high-moisture wheat during malfunctioning airtight storage in laboratory experiments. The use of Pichia anomala to improve the postharvest control of Penicillium roqueforti during airtight storage of feed grain was evaluated in outdoor silos. Inoculated and control winter wheat (cultivar Kosack) in 160-kg portions were stored at a water activity of 0.93 for 12 months in silos that were opened twice a week. During the first 2 months, inoculated Pichia anomala increased to about 10(7) colony-forming units (CFU)/g, while naturally occurring Pichia anomala in the treatments without inoculated yeast increased from 10(4) to 10(6) CFU/g. During the same period, CO2 concentrations increased to almost 70% and stabilized at 50-60%. During the coldest period, O-2 concentrations of <1% could be detected between samplings, whereas during the rest of the storage detectable O-2 levels were only found immediately after sampling. There were no clear differences in CO2 or O-2 levels between treatments. The inoculated Penicillium roqueforti did not grow during the storage period, probably owing to high numbers of Pichia anomala in combination with the high CO2 and low O-2 concentrations in the silos. In laboratory experiments, it was found that Pichia anomala survived long-term storage in airtight sealed test tubes better at 15 degrees C than at - 20 degrees C. The aerobic stability of moist wheat after 10 and 12 months of silo storage was clearly enhanced by an initial inoculation with Pichia anomala.
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| 7. |
- Abrahamsson, Lillemor
(författare)
-
Matvanor och behov under livscykeln
- 1999
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Ingår i: Näringslära för högskolan. - : Liber AB Stockholm. ; , s. 289-316
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 8. |
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| 9. |
- Adamek, P
(författare)
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Mögelsvampar
- 1991
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Rapport (refereegranskat)
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| 10. |
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| 11. |
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| 12. |
- Ahlstrom, R., et al.
(författare)
-
School children's preferences for food combinations
- 1990
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Ingår i: Food Quality and Preference. - 0950-3293 .- 1873-6343. ; 2:3, s. 155-165
-
Tidskriftsartikel (refereegranskat)abstract
- Students from the 4th, 8th and 11th grades (N = 177) expressed their opinions as to which foodstuffs belong together in a meal. They did this by selecting and grouping cards that depicted the names and pictures of 25 foodstuffs typically offered in their school lunches. Subjects were allowed to create up to 10 different meals under one of four instructions. The cards were dispensed from a specially designed box that could hold single or multiple copies of each food item. Younger students created significantly more meals with few components than did the older students. The types of foodstuffs selected and their groupings were highly similar across grades and for both boys and girls. The meals tended to correspond to those actually available in the school lunch program, but more than 50% of the creations were unique in that each of them was produced by one or two students. These findings suggest that school nutritionists and administrators should strive for maximum variety in their lunch menus. © 1991.
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| 13. |
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| 14. |
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| 15. |
- Alsterlund, Rolf, et al.
(författare)
-
Yersinia enterocolitica-utbrott på Bjärehalvön visar på risker med kylda matvaror
- 1995
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Ingår i: Läkartidningen. - Stockholm : Sveriges läkarförbund. - 0023-7205 .- 1652-7518. ; 92:12, s. 1213-1214
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Tidskriftsartikel (refereegranskat)abstract
- På sensommaren 1988 hade man i Skåne ett stort lokalt utbrott med 61 fall av infektioner med Yersinia enterocolitica. DEn kliniska bilden var avsevärt mildare än som brukar rapporteras, med diarré, magsmärtor och feber som dominerande symtom, och endast två fall av svårare komplikationer. Den sannolika smittkällan var mjölk från ett litet mejeri där hygienen inte var den bästa, Utbrottet visar på en av många risker med distribution av industriellt framställda kylda livsmedel.
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| 16. |
- Andersson, Annika, et al.
(författare)
-
Adhesion and removal of dormant, heat-activated, and germinated spores of three strains of Bacillus cereus
- 1998
-
Ingår i: Biofouling (Print). - 0892-7014 .- 1029-2454. ; 13:1, s. 51-67
-
Tidskriftsartikel (refereegranskat)abstract
- As the spores of Bacillus cereus are known to be very adhesive, the cleaning processes used to eliminate them are often inefficient. This study investigated how adhesion and removal of spores varied among strains of the species B. cereus. The adhesion and removal of spores during their life cycle were also examined. Spores of three different strains of B. cereus, viz. NVH 61, 1AM 1110 and NCTC 2599, were used. IAM 1110 spores adhered in greater numbers than spores of the other two strains and were the most hydrophobic; four times as many spores of this strain adhered than of the least adhesive spores, NCTC 2599. Spores of both these strains have an exosporium and appendages, but as the relative hydrophobicity varies, there are probably differences in their chemical composition. It was also found that dormant spores were 33-48% more adhesive than germinated spores. There were no obvious differences in adhesion between dormant and heat-activated spores. Up to 80% of the germinated spores could be removed from the surfaces tested. Dormant and heat-activated spores on the other hand were difficult to remove from the surfaces. When siliconized glass surfaces were coated with milk, germinated spores were still the easiest to remove but the difference was not as marked as before. Therefore, this work suggests that cleaning processes should take into consideration factors that boost spore germination in order to improve the cleaning.
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| 17. |
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| 18. |
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| 19. |
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| 20. |
- Andersson, Annika, et al.
(författare)
-
Comparison between automatic ribotyping and random amplified polymorphic DNA analysis of Bacillus cereus isolates from the dairy industry
- 1998
-
Ingår i: International journal of food microbiology. - 0346-718X. ; 47:1-2, s. 147-51
-
Tidskriftsartikel (refereegranskat)abstract
- Discrimination by automatic ribotyping and random amplified polymorphic DNA PCR, RAPD, was compared for 40 different B. cereus dairy isolates, 4 different B. mycoides isolates and 6 culture collection strains. RAPD-PCR has previously shown to be useful for tracing contamination routes of B. cereus to milk. Automatic ribotyping using EcoRI and PvuII separated the B. cereus and B. mycoides isolates/strains into 36 different ribotypes. RAPD-typing with primer 1 (5?-CCGAGTCCA-3?) and primer 2 (5?-CCGGCGGCG-3?) generated 40 different RAPD-profiles. However, 17 isolates clustered into 8 groups, irrespective of the primer and restriction enzyme used and in all but one case, the isolates with the same pattern were isolated from the same dairy. To conclude RAPD-typing was only slightly more discriminatory than automatic ribotyping and therefore automatic ribotyping proved to be a useful, standardized and quick method to discriminate between B. cereus strains. As the two methods are based on completely different genetic properties, one of the methods can be used to confirm the results from the other method, when identity among isolates needs to be verified.
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| 21. |
- Andersson, Annika, et al.
(författare)
-
Comparison between automatic ribotyping and random amplified polymorphic DNA analysis of Bacillus cereus isolates from the dairy industry
- 1999
-
Ingår i: International Journal of Food Microbiology. - 0168-1605 .- 1879-3460. ; 47:42006, s. 147-151
-
Tidskriftsartikel (refereegranskat)abstract
- Discrimination by automatic ribotyping and random amplified polymorphic DNA PCR, RAPD, was compared for 40 different B. cereus dairy isolates, 4 different B. mycoides isolates and 6 culture collection strains. RAPD-PCR has previously shown to be useful for tracing contamination routes of B. cereus to milk. Automatic ribotyping using EcoRI and PvuII separated the B. cereus and B. mycoides isolates/strains into 36 different ribotypes. RAPD-typing with primers generated 40 different RAPD-profiles. However, 17 isolates clustered into eight groups, irrespective of the primer and restriction enzyme used, and in all but one case, the isolates with the same pattern were isolated from the same dairy. Automatic ribotyping proved to be a useful, standardized and quick method to discriminate between B. cereus strains, only slightly less discriminatory than RAPD-typing.
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| 22. |
- Andersson, Annika, et al.
(författare)
-
The adhesion of Bacillus cereus spores to epithelial cells might be an additional virulence mechanism
- 1998
-
Ingår i: International Journal of Food Microbiology. - 0168-1605 .- 1879-3460. ; 39:1-2, s. 93-9
-
Tidskriftsartikel (refereegranskat)abstract
- Four out of ten Bacillus cereus strains produced spores able to adhere to monolayers of Caco-2 cells (human epithelial cells). One of these strains has been involved in an outbreak of food poisoning where the symptoms were more severe and persisted for longer than a normal B. cereus food poisoning. The hydrophobicity of the spores is a contributing factor for the adhesion to occur. The spores are able to germinate in an environment similar to that of the small intestine and then the vegetative cells can produce the enterotoxin directly at the target place. A concentrated and active form of the enterotoxin will be taken up by the epithelial cells in the small intestine. Spore adhesion could be an important virulence factor for some B. cereus strains.
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| 23. |
- Andersson, Annika, et al.
(författare)
-
What problems does the food industry have with the spore-forming pathogens Bacillus cereus and Clostridium perfringens?
- 1995
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Ingår i: International Journal of Food Microbiology. - 0346-718X. ; 28:2, s. 14-55
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Tidskriftsartikel (refereegranskat)abstract
- Spore-forming Bacillus cereus and Clostridium perfringens bacteria are special problems for the dairy and meat industry, respectively. Proper cleaning and disinfection with hypochlorite is essential to avoid high numbers of these bacteria in food products. It is impossible for B. cereus and C. perfringens to cause food poisoning with cooking and rapid cooling, and proper reheating. It is also important to note that the generation time for C. perfringens can be as short as 8 min under optimal conditions, so temperatures between 10 and 47 °C in any meat product must be restricted. B. cereus food poisoning through milk and milk products can be avoided with a low number of spores in the products and proper cooling.
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| 24. |
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| 25. |
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| 26. |
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| 27. |
- Andersson, Inger
(författare)
-
Kolhydrater
- 1999
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Ingår i: Näringslära för högskolan. - : Liber AB Stockholm. ; , s. 38-52
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 28. |
- Andersson, Inger
(författare)
-
Kostinformation
- 1999
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Ingår i: Näringslära för högskolan. - : Liber AB Stockholm. ; , s. 332-339
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 29. |
- Andersson, Inger
(författare)
-
Kostplanering och bedömning
- 1999
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Ingår i: Näringslära för högskolan. - : Liber AB Stockholm. ; , s. 275-288
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 30. |
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| 31. |
- Andersson, Karin, et al.
(författare)
-
Including environmental aspects in production development : A case study of tomato ketchup
- 1999
-
Ingår i: Lebensmittel-Wissenschaft + Technologie. - 0023-6438 .- 1096-1127. ; 32:3, s. 134-141
-
Tidskriftsartikel (refereegranskat)abstract
- An environmental Life Cycle Assessment (LCA) study of a specific tomato ketchup was carried out. The objectives of the work were to illustrate how LCA can be used in production development; to investigate the influence of the geographical location of certain processes; and to find ways to improve the product's environmental performance. In the screening LCA which includes the whole life cycle, the packaging and processing sub-systems were found to be significant in the total environmental impact made by ketchup. Accordingly, six alternative systems, including packaging, processing and transportation, were modelled and simulated. The environmental impact categories included were energy use, global warming, acidification, eutrophication, photo-oxidant formation and the generation of radioactive waste. It was concluded that the current geographical location of the production of ketchup is preferable; the contributions to acidification can be reduced significantly; and the environmental profile of the product can be improved for either the type of tomato paste currently used or a less concentrated tomato paste. A shift to a less concentrated paste would also mean that traditional quality parameters of the ketchup could be improved. © 1999 Academic Press.
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| 32. |
- Andersson, Karin, et al.
(författare)
-
Influence of oxygen and copper concentration on lipid oxidation in rapeseed oil
- 1998
-
Ingår i: Journal of the American Oil Chemists Society. - 0003-021X .- 1558-9331. ; 75:8, s. 1041-1046
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Tidskriftsartikel (refereegranskat)abstract
- The influence of oxygen concentration and copper on lipid oxidation in rapeseed oil during storage at 40°C was investigated. The oil was stored in air, or with 1.1%, 0.17%, or 0.04% oxygen in the headspace, and 70 or 0.07 ppm copper was added. Volatile oxidation products and oxygen consumption were monitored. Addition of 70 ppm copper to the sample in air resulted in a 70-fold higher hexanal concentration after 35 d of storage, compared to the sample without added copper. The addition of 0.07 ppm copper to the sample stored in air gave a doubled hexanal concentration, compared to the sample without copper, after 35 d of storage. For the samples with 70 ppm copper at 0.17% and 0.04% oxygen, all oxygen was consumed after 7 d of storage. The results show the importance of minimizing the oxygen available for oxidation, especially when pro-oxidants are present. In the sample with 70 ppm added copper, in air, the hexanal increase was 65 times larger than for the same sample in 0.04% oxygen. A comparison of the effect of oxygen or copper on oxidation shows that the addition of 70 ppm copper to the 0.04% oxygen sample gave the same increase in hexanal content as an oxygen increase to 0.17%.
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| 33. |
- Andersson, Karin, et al.
(författare)
-
Influence of oxygen concentration and light on the oxidative stability of cream powder
- 1998
-
Ingår i: Lebensmittel-Wissenschaft + Technologie. - 0023-6438 .- 1096-1127. ; 31:2, s. 169-176
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Tidskriftsartikel (refereegranskat)abstract
- The production of volatile oxidation products and consumption of oxygen were measured in cream powder stored for 35 weeks at 30 °C in darkness or exposed to fluorescent light. The headspace of the bottles contained either air (209 mL O 2/L) or 13, 3.5, 0.4 or 0.3 mL/L oxygen in nitrogen. The exposure to light strongly influenced both the rate of hexanal production and oxygen consumption. After the first 5 weeks of storage in light, significantly different oxygen-dependent increases in hexanal were found for all samples. Although the samples stored in darkness showed a much smaller hexanal increase, it was still significant during storage. After 35 weeks of storage, the dark-stored sample in air showed a highly significant larger hexanal increase than all the other samples stored in darkness, but after the same storage period, the hexanal increase in the 13, 3.6 and 0.4 mL O 2/L samples was the same. The production of the Strecker aldehyde, 3-methylbutanal, was found to depend on light and to some extent on oxygen concentration, which indicates that lipid oxidation also influenced the conditions of the Maillard reaction. © 1998 Academic Press Limited.
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| 34. |
- Andersson, Karin, et al.
(författare)
-
Influence of oxygen concentration on the flavour and chemical stability of cream powder
- 1998
-
Ingår i: Lebensmittel-Wissenschaft + Technologie. - 0023-6438 .- 1096-1127. ; 31:3, s. 245-251
-
Tidskriftsartikel (refereegranskat)abstract
- Descriptive sensory analysis and analysis of hexanal content were performed on cream powder stored in darkness at different oxygen concentrations at 30 °C for up to 45 weeks. The headspace of the samples contained 209 (air), 13, 3.6, 0.4 or 0.3 m/L oxygen/L headspace gas. All samples stored with reduced oxygen content were, with one exception, significantly different from the air-packed sample after 25 as well as after 45 weeks of storage, both in their hexanal concentration and according to sensory analysis. However, there were no significant sensory differences between the samples stored with reduced oxygen for 25 or 45 weeks. Analysis of the hexanal concentration in the samples was a more sensitive method than sensory analysis for detecting differences between samples stored for the same length of time. Furthermore, some of the samples with reduced oxygen concentration were found to differ significantly in their hexanal concentration. Significant differences between samples before storage and samples stored for 25 or 45 weeks, regardless of oxygen concentration, were found by both sensory and chemical analyses. © 1998 Academic Press.
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| 35. |
- Andersson, Karin, et al.
(författare)
-
Influence of oxygen concentration on the storage stability of cream powder
- 1997
-
Ingår i: Lebensmittel-Wissenschaft + Technologie. - 0023-6438 .- 1096-1127. ; 30:2, s. 147-154
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Tidskriftsartikel (refereegranskat)abstract
- The influence of low oxygen concentrations on lipid oxidation during storage of cream powder was studied. The powder was packed with oxygen concentrations of 209 mL/L, 17 mL/L, 8.3 mL/L, 3.4 mL/L, 1.5 mL/L, 0.7 mL/L and 0.6 mL/L and stored in darkness at 30°C for 29 weeks. To follow oxidation, the formation of volatile oxidation products and oxygen consumption were measured. After 7 weeks of storage a significant (P <0.01) hexanal development was already seen in all the samples, and the hexanal content was directly related to the initial oxygen content, with one exception, the 0.6 mL/L sample, which had a slightly (but not significantly, P >0.05) higher hexanal content than the 0.7 mL/L sample. There were only small differences in hexanal formation between the samples packed with oxygen concentrations below 3.4 mL/L. This could be due to a more pronounced influence of oxygen diffusion at these low levels of oxygen, leading to a diffusion-controlled oxidation. Other volatiles, not produced by lipid oxidation, also increased during storage. The formation of Strecker aldehydes was found to be oxygen-dependent, whereas the formation of 2-alkanones was not. Measurement of oxygen consumption was not sufficient to detect differences in oxidation rate between the samples packed with 17 mL/L oxygen and less. © 1997 Academic Press Limited.
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| 36. |
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| 37. |
- Andersson, Karin, et al.
(författare)
-
Kinetic studies of oxygen dependence during initial lipid oxidation in rapeseed oil
- 1999
-
Ingår i: Journal of Food Science. - 0022-1147 .- 1750-3841. ; 64:2, s. 262-266
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Tidskriftsartikel (refereegranskat)abstract
- Lipid oxidation was studied in rapeseed oil, stored at 35 or 50°C in 0.03, 0.3, 1.0 or 1.8% oxygen for 42 days. Peroxide value (PV), oxygen consumption, tocopherol consumption and production of volatile compounds were analyzed to follow the oxidation. At 50°C, lipid oxidation measured as oxygen consumption or PV was only slightly influenced by oxygen concentration ?1%. Below 0.5% the influence was strongly enhanced. The production of volatiles showed different relationships to oxygen concentration and some compounds were produced in larger amounts at lower O2, than at higher O2 concentrations.
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| 38. |
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| 39. |
- Andersson, Karin, et al.
(författare)
-
Life cycle assessment (LCA) of food products and production systems
- 1994
-
Ingår i: Trends in Food Science & Technology. - 0924-2244 .- 1879-3053 .- 0346-718X. ; 5:5, s. 134-138
-
Tidskriftsartikel (refereegranskat)abstract
- In the late 1980s the demands for a more ecological life style and sustainability set off intense research for methods to analyse and assess the environmental impact of products and systems. The methodology crystallizing from this research is called life cycle assessment (LCA). This paper presents the concept, methodology, applications and present status of LCA. LCA as applied to food production systems is discussed in terms of needs, special demands on methodology, the studies that have been performed and ongoing activities. © 1994.
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| 40. |
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| 41. |
- Andersson, Karin, et al.
(författare)
-
Life cycle assessment of bread produced on different scales
- 1999
-
Ingår i: The International Journal of Life Cycle Assessment. - 0948-3349 .- 1614-7502 .- 0346-718X. ; 4:1, s. 25-40
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Tidskriftsartikel (refereegranskat)abstract
- A case study of white bread has been carried out with the purpose of comparing different scales of production and their potential environmental effects. The scales compared are: home baking, a local bakery and two industrial bakeries with distribution areas of different sizes. Data from the three bakeries and their suppliers have been collected. The systems investigated include agricultural production, milling, baking, packaging, transportation, consumption and waste management. Energy use and emissions have been quantified and the potential contributions to global warming, acidification, eutrophication and photo-oxidant formation have been assessed. The large industrial bakery uses more primary energy and contributes more to global warming, acidification and eutrophication than the other three systems. The home baking system shows a relatively high energy requirement; otherwise, the differences between home baking, the local bakery and the small industrial bakery are too small to be significant.
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| 42. |
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| 43. |
- Andersson, Karin, et al.
(författare)
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Screening life cycle assessment (LCA) of tomato ketchup : A case study
- 1998
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Ingår i: Journal of Cleaner Production. - 0959-6526 .- 1879-1786. ; 6:3-4, s. 277-88
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Tidskriftsartikel (refereegranskat)abstract
- A screening life cycle assessment (LCA) of tomato ketchup has been carried out. The purpose was to identify 'hot-spots', that is parts of the life-cycle that are important to the total environmental impact. The system investigated includes agricultural production, industrial refining, packaging, transportation, consumption and waste management. Energy use and emissions were quantified and some of the potential environmental effects assessed. Packaging and food processing were found to be hot-spots for many, but not all, of the impact categories investigated. For primary energy use, the storage time in a refrigerator (household phase) was found to be a critical parameter. © 1998 Elsevier Science Ltd. All rights reserved.
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| 44. |
- Andersson, Karin, et al.
(författare)
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The feasibility of including sustainability in LCA for product development
- 1998
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Ingår i: Journal of Cleaner Production. - 0959-6526 .- 1879-1786. ; 6:3-4, s. 289-98
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Tidskriftsartikel (refereegranskat)abstract
- The feasibility of combining the concept of sustainability principles and the methodology of Life Cycle Assessment (LCA) is examined. The goal is to achieve an operational tool that incorporates sustainability in product development and strategic planning. While the method outlined has the structure of LCA, it emphasises aspects and parameters often omitted from traditional LCA. The analysis and results can be either qualitative or semi-quantitative. Although a qualitative analysis is less time consuming, it can still highlight the important issues. Qualitative information, which is easily lost in a quantitative analysis, can be emphasised. One of the conclusions is that the method is well suited for screening analysis. © 1998 Elsevier Science Ltd. All rights reserved.
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| 45. |
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| 46. |
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| 47. |
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| 48. |
- Andersson, Yngve, et al.
(författare)
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Extruded wheat flour. : Correlation between processing and product quality parameters
- 1990
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Ingår i: Food Quality and Preference. - 0950-3293 .- 1873-6343. ; 2:4, s. 201-216
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Tidskriftsartikel (refereegranskat)abstract
- The influence of independent processing parameters on the product properties of extruded mixtures of wheat flour and water has been investigated. Physical, chemical, and sensory measurements are reported and correlated with underlying processing parameters. Such correlation could be used to automate and control the extrusion process. © 1991.
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| 49. |
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| 50. |
- Anker, M., et al.
(författare)
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Effects of pH and the gel state on the mechanical properties, moisture contents, and glass transition temperatures of whey protein films
- 1999
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Ingår i: Journal of Agricultural and Food Chemistry. - : American Chemical Society (ACS). - 0021-8561 .- 1520-5118. ; 47:5, s. 1878-1886
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Tidskriftsartikel (refereegranskat)abstract
- The mechanical properties, moisture contents (MC), and glass transition temperature (T(g)) of whey protein isolate (WPI) films were studied at various pH values using sorbitol (S) as a plasticizer. The films were cast from heated aqueous solutions and dried in a climate chamber at 23 °C and 50% relative humidity (RH) for 16 h. The critical gel concentrations (c(g)) for the cooled aqueous solutions were found to be 11.7, 12.1, and 11.3% (w/w) WPI for pH 7, 8, and 9, respectively. The cooling rate influenced the c(g), in that a lower amount of WPI was needed for gelation when a slower cooling rate was applied. Both cooling rates used in this study showed a maximum in the c(g) at pH 8. The influence of the polymer network on the film properties was elucidated by varying the concentration of WPI over and under the c(g). Strain at break (?(b)) showed a maximum at the c(g) for all pH values, thus implying that the most favorable structure regarding the ability of the films to stretch is formed at this concentration. Young's modulus (E) and stress at break (?(b)) showed a maximum at c(g) for pH 7 and 8. The MC and ?(b) increased when pH increased from 7 to 9, whereas T(g) decreased. Hence, T(g) values were -17, -18, and -21 °C for pH 7, 8, and 9, respectively. E and ?(b) decreased and ?(b) and thickness increased when the surrounding RH increased. The thickness of the WPI films also increased with the concentration of WPI.
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