Microfilms packaging and coating: effects on shelf life and quality of African pear (Dacryodes edulis) fruits

Studies on storage potential of African pear fruits (APFs) were conducted using three packaging microfilms (low density polyethylene, low density polypropylene and highdensity polypropylene) and three coating materials (sheanut butter, palm oil and paraffin wax). The packaged and coated APFs were separately stored at ambient temperature  (300±30C) and two refrigeration temperatures (100C and50C). Among all the packaged and coated pears held at 300±30C, only the low density polyethylene packaged ones were able to remain wholesome beyond six days maximum storage period for untreated pears held at same ambient temperature. And among the three coating materials, paraffin wax was the best for APFs held at cold storagetemperatures of 100C and 50C. At these two refrigeration  temperatures, the shelf life periods of the paraffin coated pears were extended respectively to 24 and 33 days. At the refrigeration temperature of 100C, the longest storage period of 33 days was achieved for APFs packaged with lowdensity polypropylene. And the longest storage period of 42 days was obtained for APFs packaged in high density polypropylene and held at 50C

Composite Flours for Baked Products and Possible Challenges – A Review

This paper is a review of how consumption of bread, other leavened products and unleavened products made from wheat flour has increased rapidly in Nigeria and other developing countries. It examines how this has resulted in large scale importation of wheat and the consequent drain on the nation’s foreign currency earnings. It contains some suggestions on how to reduce the high import bills of wheat by using composite flours or blends of wheatless flours in place of wheat flour for making leavened and unleavened products. Some studies on the quality characteristics of leavened and unleavened products made from composite flours or blends of wheat flours were reviewed. Some possible challenges likely to be encountered in case Nigeria changes from use of wheat flour to composite flours and blends of wheatlessflours are also outlined.Keywords: Wheat, composite, flour, products, challenges

Effects of storage temperature and humidity on shelf life and quality of African pear (Dacryodes edulis) fruits

The post harvest quality of African pear (Dacryodes edulis) fruits stored at ambient and refrigeration temperatures (300C, 100C and 50C) under the ambient vapour pressure and three relative humidities (65%, 75% and 81%) was studied. Results showed that the rates of growth of microorganisms, moisture loss, weight loss, browning and softening rates increased rapidly for all the African pear fruits stored atambient temperature (300C) in the four respective humidities. However, the quality losses as well as microbiological growths were drastically reduced when the fruits were stored at the lowest storage temperature (50C) and under three relative humidity regimes of 65%, 75% and81%. The African pear fruits stored at 50C under ambient vapour pressure have an average shelf life of 27days as against 31 days average recorded for those stored in 65%-81% relative humidity. Storage in this medium relative humidity (65%-81%) at refrigeration temperature of 100C extended the shelf life of African pear fruits to an average of 24 days as against 18 days which was recorded for pearsstored at the same refrigeration temperature at ambient vapour pressure

Effect of chemical preservation on the shelf-life of bottled intermediate moisture tomato paste stored at ambient temperature

Six samples of bottled intermediate moisture tomato paste were stored at ambient conditions (33-38°C). Four of the samples were preserved with chemicals. One of the last two samples which was bottled with no chemical preservatives added had palm oil filled onto its headspace. Shelf-like studies conducted for forty weeks showed no appreciable changes in chemical properties of samples mixed with sodium metabisulphite and sodium benzoate. The samples with vinegar and palm oil filled headspace showed changes in chemical properties from the 13th week of storage. Chemical changes were noticed on the 10th and 4th week respectively for sodium chloride treated and untreated control paste samples. There was no significant difference in organileptic properties of all the samples in the first 8 weeks of studies with the exception of untreated control sample, which was rated lower (

Effects of Holding Methods and Time on the Vitamin Contents of Five Tropical Leafy Vegetables

Five tropical leafy vegetables, Pterocarpus soyauxii (“oha”), Pterocarpus santalinodes (“nturukpa”), Gongronema latifolium (“utazi”), Corchorus olitorius (“ahihiara”) and Amaranthus hybridus (“green”) were held for four days at ambient condition using three different popular local methods used in the Southeastern states of Nigeria. Each leafy vegetable was divided into three lots. Lots I and II were unwrapped while lot III was wrapped with broad cocoyam leaves. The three lots were held under a shade. In addition, lot II was regularly taken outside to the open at nights where it was exposed to cool air and early morning dews. The vitamin contents of each leafy vegetable lot were analysed initially and on daily basis for four days. The beta carotene and ascorbic acid contents ranged respectively from 4.88 – 9.84ìg and 105.62 – 278.65 mg per l00 g of the leafy vegetable. The five leafy vegetables are fair sources of thiamin, riboflavin and niacin. There were losses in the vitamins as holding time increased, regardless of the holding method employed. The rate of loss of vitamins was highest in Lot I (the unwrapped leaves that were kept in a shade both day and night). The rate of loss of vitamins was lowest in Lot III (the wrapped leafy vegetables).Keywords: Leafy vegetables, vitamins, method, time, loss

The Quality Properties Of Tomatoes (Lycopersicon esculentum) As Influenced By Processing With A Chemical Preservative And Storage

Blanched sulphited and unblanched unsulphited tomato slices (control) were subjected to different storage temperatures (6-8oC) and (-12oC) respectively for 15 weeks. Solar dried (blanched sulphited and unblanched unsulphited) tomato slices were stored at ambient temperature (28-30oC). Within the 15 weeks of storage, ascorbic acid,pH, titratable acidity, microbial population and sensory attributes were determined Blanched sulphited frozen (BLSF), unblanched unsulphited frozen (UNUF), blanched sulphited solar dried (BLSSD) and unblanched unsulphited solar dried (UNUSD) samples showed a decrease in pH with an increase in titratable acidity during storage. On the other hand blanched sulphited refrigerated (BLSR) and unblanched unsulphited refrigerated (UNUR) samples had an increase in pH and a decrease in titratable acidity. The moisture content of both frozen and solar dried samples reduced but that of refrigerated samples increased. The frozen samples retained more ascorbic acid (69.26% for BLSF and 55.41% for UNUF) than other samples but the blanched sulphited frozen sample retained the highest ascorbic acid (69.26%). The solar dried samples were better (45% for BLSSD and 48.15% for UNUSD) than the refrigerated samples which retained lesser ascorbic acid (30.57% for BLSR and 26.55% for UNUR). The frozen and solar dried samples showed an appreciable decrease of microbial population while there was an increase in the refrigerated samples at the end 15 weeks. Sensory evaluation indicated no significant differences in colour, flavour, texture and general acceptability between the blanched sulphited frozen and the fresh tomatoes at P< 0.05. Blanched sulphited solar dried and unblanched unsulphited solar dried samples were inferior in color, texture and general acceptability but not in flavour. Key words: Blanching, sulphiting, Solar drying, Tomatoes. Nigerian Food Journal Vol.22 2004: 195-20

Effects of Some Tropical Plant Oils Supplemented Diet on Blood Serum Lipid Profile of Albino Rats

Oils were extracted from African pear (Dacryodes edulis) fruits, bullet pear (Cemarium schweinfurthii) fruits, melon (Colocynthis citrullus) seeds and groundnuts (Arachis hypogaea). Oil yields from each of these plants crops were not less than 52% and the fatty acids range were palmitic (19.25-27.37%), stearic (16.30-21.09%), oleic (15.07-26.75%), linoleic (18.60-26.10%) and linolenic (13.20-16.40%). The oils were respectively used at 10% level as supplement to formulate rat feeds. The supplemented feed and control feed (feed with none of these oils) were each fed to a group (seven) of albino rats for sixty days. The effects of the feeds on the blood  serum lipid profile of the albino rats were determined. The albino rat group fed with bullet pear fruit oil feed recorded the highest weight gain of 57.89%. There were no significant differences (p &lt; 0.05) in the total cholesterol, triglyceride, and high density lipoprotein contents in the blood serum of the albino rats. However, the low density lipoprotein cholesterol content of 26.43mg/ dl in the blood serum of albino rat in group on bullet pear fruit oil supplemented feed was significantly (p &lt; 0.05) higher than the values obtained for the rat groups on the other oil supplemented feeds. Regression analysis results showed that there was no relationship between some of the fatty acids of the plant oils and blood serum triglycerides, high density lipoprotein cholesterol and very low density lipoprotein cholesterol except that of palmitic and stearic acids of bullet pear fruit oil which showed strong relationship with total and low density lipoprotein cholesterol.Keywords: Pear fruits, groundnut, melon, fatty acids, cholesterol