Paleoenvironmental records from the Quelccaya ice cap, Peru and preliminary results from the Dunde ice cap, China [abstract]

EXTRACT (SEE PDF FOR FULL ABSTRACT): The 1000 year records of particulate deposition (soluble and insoluble), oxygen isotopic ratios, and net accumulation from the Quelccaya ice cap are presented. The net accumulation record from Quelccaya is shown to serve as a reasonable proxy for the water levels in Lake Titicaca. ... The ice core record from the Dunde ice cap offers the potential to reconstruct a very detailed history of environmental conditions on the Tibetan Plateau for the last 3000 years.

Initial global perspective of climate for the last thousand years: the ice core record

Climatic and environmental records from low, middle, and high latitude ice cores greatly increase our knowledge of the course of past events. This historical perspective is essential to predict climatic oscillations, dominated as they may be by increasing greenhouse gas concentrations. Forcing factors, internal and external, that have operated in the past will continue to influence the course of events.

The Little Ice Age: glacier variations and climate since AD 1250 [abstract]

EXTRACT (SEE PDF FOR FULL ABSTRACT): During the past hundred years, mountain glaciers throughout the world have retreated significantly from moraines built during the previous several centuries. In the 1930s, Francois Matthes of the U.S. Geological Survey concluded that the moraines represent the greatest advances of glaciers since the end of the last glacial age, some 10,000 years earlier, and informally referred to this late Holocene interval of expanded ice cover as the Little Ice Age.

Effect of aureomycin on the behaviour of certain free amino acids in oil sardine (Sardinella longiceps) held in ice storage

The course of development of a few free amino acids under the influence of aureomycin in oil sardine (Sardinella lingiceps) held in ice storage was investigated. The levels of leucines and valine regularly increased in the control and aureomycin treated fush throughout the storage period. Alanines and threonine showed similar trend in both control and fish treated with 20ppm aureomycin. These amino acids however showed a gradual fall in fish treated at 5 ppm level. The changes in tyrosine+tryptophane were found to be irregular. Most of the amino acids studied indicated a remarkable change in trend by about the 16th day of ice storage in the case of fish treated with 50ppm aureimycin.

Influence of ice on the bacteriological quality of the processed fishery products

The influence of ice on the bacteriological quality of the processed fishery products has been discussed. In almost all the cases ice has been traced to be a major source of contamination depending on the nature of water used for preparing it. The sources of contamination of ice and its remedies have been described.

Studies on the post-mortem changes in shrimp and prawn during ice storage. Pt. 1. Organoleptic and physical changes

The organoleptic characteristics such as appearance, textural condition, colour and odour indicated that the M. rosenbergii stored in ice for 5-6 days was acceptable for processing in the industry while P. monodon under similar ice storage condition was acceptable for 8-9 days. In both species, samples stored in headless condition in ice had longer shelf life than that of stored in head-on condition. Physical changes were evaluated by determining expressible moisture and breaking strength of sample of muscles. The expressible moisture increased continuously in both samples with the lapse of storage period. The expressible moisture increased up to around 44% in 4-5 days of ice stored M. rosenbergii muscle while it was around 40% in 8-9 days ice stored P. monodon. At the end of 9 days of ice storage, the expressible moisture content in M. rosenbergii increased up to 60%, while it was up to 47% in P. monodon after 11 days of ice storage. The breaking strength declined from 0. 78 kg/cm² to 0.53 kg/cm² in tiger shrimp after 8 days of ice storage, while in case of immediately killed prawn, the breaking strength of muscle was 0.8 kg/cm² which declined to 0.43 to 0.35 kg/cm².

Studies on the post-mortem changes in shrimp and prawn during ice storage. Pt. 2. Biochemical aspects of quality changes

Studies were conducted on biochemical changes in P. monodon and M. rosenbergii during ice storage. At the end of 10 days of ice storage, moisture and protein content of freshwater prawn slightly decreased from 78.34 to '77.35% and 18.46 to 17.10, respectively, while lipid and ash content slightly increased. The moisture, crude protein, lipid and ash content of one day ice stored tiger shrimp samples were 78.07, 18.06, 1.3 and 1.29% respectively. The protein composition of freshwater prawn immediately after killed were 36.51% sarcoplasmic, 44.63% myofibrillar, 8.12% stroma and 6.44% alkali soluble protein. At the end of 10 days of ice storage, sarcoplasmic and stroma protein slightly decreased while there was little or no changes observed in myofibrillar and alkali soluble protein. In case of one day ice stored tiger shrimp, the composition of protein were 35.32% sarcoplasmic, 46.29% myofibrillar, 7.86% stroma protein and 7.08% alkali soluble protein. At the end of 10 days in ice, sarcoplasmic protein decreased from 35.32% to 32.16% while there was slight change in other protein fractions. The TVB-N value of 1 day ice stored shrimp was 10.5 mg/100g of sample. It increased gradually with the lapse of storage period and at the end of 10 days storage in ice, the value increased up to 60 mg/100g sample. The tiger head on shrimp in ice storage were found organoleptic acceptable condition for 8 days and at that time the TVB-N values were 32.2 mg/100g which is slightly above the recommended limit for TVB-N for export.

Suitability of ice stored mackerel and sardine for canning

The paper reports the results of studies on ice storage and subsequent canning of mackerel (Rastrelliger kanagurta) and Sardines (Sardinella longiceps) and the effect of such storage on the quality of the canned product prepared out of them. The changes in the physical and chemical characteristics during ice storage are determined and correlated with the quality of the finished product.

Technological aspects of processing of edible mussels, clams and crabs. Pt. 1. Spoilage during ice storage

Rate and pattern of spoilage of some of the economically important edible species of shell fishes Mytilus edulis (Mussel), Villorita cornucopia (Clam), Neptunus pelagicus (Crab) and Scylla serrata (Crab) have been discussed in this communication. Chemical indices used for objective evaluation of quality were water extractable nitrogen (WEN), non-protein nitrogen (NPN), free α-amino nitrogen (α - NH2 -N), glycogen, lactic acid and inorganic phosphorus in addition to the subjective tests. No significant difference in the spoilage pattern of the species during ice storage was observed and these species could be preserved in ice in organoleptic acceptable condition up to 8 days, 9 days, 8 days and 11 days respectively.

Observations on changes in the major protein nitrogen fraction of prawns and sardines during ice storage

Changes in the major protein nitrogen fractions (sarcoplasmic, myofibrillar, stroma) have been studied in two species of prawns and in oil sardine held in ice storage. Myofibrillar proteins were observed to get denatured at a rapid rate as determined by salt extractability method. The sarcoplasmic proteins were not denatured to any considerable extent. With sardine however, the extraction of myofibrillar proteins was inhibited rather in the uniced condition itself presumably owing to the presence of free fatty acids.

Ice storage characteristics of cultured silver carp

Cultured silver carp (Hypopthalmichthys molitrix 800-1000 g) was stored in ice (fish to ice ratio 1:1) in a plywood box insulated with one inch thick expanded polystyrene and subjected to detailed examination of quality by chemical, microbiological and organoleptic evaluation at regular intervals to assess the storage life in good acceptable form. Alpha-amino nitrogen, non-protein nitrogen and pH values showed no positive correlation as spoilage index. Total volatile base nitrogen was not high at the end of the storage period although the fish became unacceptable during the period. There was steep decrease in total bacterial count during initial stages of storage and then increased steadily on further storage. Organoleptic evaluation of raw and cooked meat revealed that fish was in good acceptable form up to 14 days in ice.

Ice storage characteristics of cultured Macrobrachium rosenbergii (de Man)

Cultured Macrobrachium rosenbergii (Scampi; 30-40 g) in headless shell-on form was stored in ice (Prawn:ice=1:2) in a plywood box insulated with 2 cm thick expanded polystyrene and subjected to detailed examination of quality by chemical, microbiological and organoleptic evaluation at regular intervals to assess the storage life. The prime quality life of prawns in ice was found to be 8 days followed by a phase of lowered quality, but still acceptable till the end of 13 days.

The storage of red snapper (Lutjanus spp.) in ice, chilled sea water and chilled fresh water

The results are given of trials conducted to determine the effect on quality of holding fish (Lutjanus species) in chilled freshwater and also to compare the quality loss of fish stored in chilled seawater and chilled freshwater and in ice. No adverse effects were observed when storing in chilled freshwater apart from loss of external appearance after 6 days storage; taste panel tests showed acceptable conditions up to 15 days. Chilled seawater is unsuitable for storage as it spoils the intake of salt from the medium, making the flesh unpalatable.

Ice storage characteristics of fresh and brined shark fillets

Ice storage characteristics of fresh and brined fillets from fresh shark (Carcharias melanopterus) were studied in and out of contact with ice for more than two weeks. Changes occurring in biochemical constituents, physical qualities and bacterial counts of the fillets are reported. Shelf life of brined fillets out of contact with ice was considerably longer than that of control samples tinder similar conditions. Icing of shark fillets is suggested as a method for the removal of urea on a commercial scale.