实验食品化学杂志

Foodborne diseases are among the most widespread public health problems and are human infections transmitted through ingested food, and caused by pathogens whose natural reservoir is a vertebrate animal species. Globally, foodborne diseases resulted in over 600 million illnesses and 420,000 deaths in 2010.The majority of the pathogens causing microbial foodborne diseases are considered to be zoonotic. Presently, there are more than 350 zoonoses of multiple etiologies, which are reported from developing as well as developed nations of the world. However, listeriosis has received special attention due to the severity of infections resulting into high morbidity and mortality. Among the various species of the genus Listeria, Listeria monocytogens is recognized as the principal cause of listeriosis in humans as well as animals including birds. The most common route of infection of humans is consumption of foods contaminated by L. monocytogenes. Raw milk, pasteurized milk, soft cheeses, ice cream, meat and meat products, fish and fish products, eggs and egg products, fruits and vegetables may serve as important sources of L. monocytogenes. The organism can survive and grow over a wide range of environmental conditions such as refrigeration temperatures, low pH and high salt concentration. This allows the pathogen to overcome food preservation and safety barriers, and pose a potential risk to human health. In humans, it can lead to meningitis, encephalitis, septicemia, abortion, pneumonia, endocarditis, urethritis, diarrhea, conjunctivitis, and skin infections. The vulnerable groups are pregnant women, infants, older persons, and individuals with weakened immune system. It is recommended to undertake more sincere efforts to make sure the safe handling of various foods to minimize the contamination of L. monocytogenese, which has emerged as an important foodborne pathogen of global significance.

The aim of this study was to investigate the influence of malting on the proximate composition and amino acid profile of locally available sorghum types (local, improved and hybrid). Each sorghum type was subjected to malting after which they were analyzed. The proximate composition of the samples revealed that malting gave rise to the enhancement of protein and crude fibre content while there were reduction in the concentration of fat, ash and carbohydrate. The highest value of protein content was found in the malted Hybrid-A and Hybrid-B with an equal value of 11.45 g/100 g sample while the highest crude fibre content was found in the malted pelipeli (local sorghum type) with a value of 2.54 g/100g sample. Virtually all the amino acids (essential and non-essential) increased in value as a result of the malting process. The total essential amino acids (TEAA) in the malted sorghum grains ranged between 335.5 and 348.1 mg/g protein which fell short of the minimum recommended 35% for the maintenance of optimum human health. The quantity of each amino acid in both unmalted and malted sorghum grains respectively from different classes of the cereal was, to a great extent, not significantly different (p<0.05). The amino acid profile therefore serves as an indicator of knowing the extent of complementarity with other protein-rich plant sources in case of using the malted sorghum grains in food formulation.

Technology and nutritional composition of zamne a traditional food of Senegalia macrostachya seeds from western Africa were studied in different production sites with the aim to establish the flow diagrams and evaluate the effect of the processing on its biochemical composition. Result showed a diversity of the processing methods according to the locality. The process included mainly successive cleaning of seeds, boiling for about 3-6 h, softening with alkalinizing ash leachate. The raw seeds were composed of 26.56 ± 1.24% of crude proteins, 40.08 ± 0.49% of crude lipids, 28.02 ± 0.05% of carbohydrates and 16.19 ± 0.16% of fibres on dry matter basis. For the ready to eat zamne, the moisture content varied from 79.54 ± 0.1 to 81.27 ± 0.2%, ash content from 4.95 ± 0.06 to 9.58 ± 0.13%; total carbohydrate varied from 17.04 ± 0.08 to 22.63 ± 0.12%, protein content from 45.46 ± 2.32% to 53.52 ± 1.23%, total fibre from 21.14 ± 0.11 to 22.67 ± 0.35% and lipid from 1.02 ± 0.02 to 1.55 ± 0.15%. The products were alkaline with pH ranging between 7.55 ± 0.01 and 8.38 ± 0.00 representing a titratable acidity varying from 0.08 ± 0.004 to 0.15 ± 0.01. Processing methods caused decreases of crude lipid (80%), total carbohydrates (60%) titratable acidity (45-84%) and an increase of fibres (30-40%), proteins (13-33%) and amino acids.