This free 12 page documents by Brenntag focusses on the use of preservatives in the preservation of food and beverages.
click the image to visit the website
This is admittedly a manufacturers document, but it gives good very short overviews of micro organisms, hurdle technology, pH, Water Activity, preservatives and acidulants before detailed information on the application of preservatives in different food groups.
This is another great article from the African Journal of Food, Agriculture
, Nutrition and Development.
click the image to visit the website
It further promotes the potential of the chemical ingredients of indigenous plants. The study clearly show that Piper guinensis is the most effective within the experimental setup.
It would, however, be nice if there was a bit of information about the nature, dosage and availability of Piper guinensis. A quick look at Wikipedia indicates that it is a strong pepper like spice that would produce a spicy fish which might not suite all and that it is rather scarce and highly valued.
But very encouraging and worthy of some feasibility evaluation.
This short 2 or 3 page article is not abut the technology of preservation, but rather about the history of how preservation became so important to civilization.
Although the article does not mention newer technologies such as radiation and pressure processing and does not expand on the science of preservation, knowing the history helps to give a wider view when one considers preservation.
The author ends by saying “Interests have shifted from preserve “because we have to”, to “preserve because we like to.”. This of course applies to the modern richer urban dweller and not poor rural communities.
Its interesting to think that if urban people still had preservation capacity the Local Food movement would be much more successful!
I have often promoted fruit preservation as cheap, simple and safe technologies. This is really based on the fact that most fruits and fruit products are high acidity foods and therefore intrinsically safe to process. This is maybe an error since it excludes the preservation of animal proteins which are good sources of nutrition.
unfortunately these documents which were free downloads are no longer available as such, but visit AGROMISA to source copies.
(click image for full story online)
This online book solves this problem with a great deal of implementable information from detailed explanations of spoilage and the dangers to information on how to prepare fish and meat for processing as well as the range of processes available.
The extract from the contents below will give an overview of what is offered.
1 Introduction 6
2 Storage life and spoilage of fish and meat 8
2.1 How long can fish or meat be kept? 8
2.2 When has fish or meat gone bad? 8
2.3 Which micro-organisms spoil fish and meat? 10
2.4 Spoilage and/or fish and meat poisoning 10
2.5 How does contamination take place? 12
2.6 How does one prevent contamination? Hygiene! 12
2.7 Prevention of spoilage 13
2.8 Which method should be chosen? 15
3 Preparation of fish and meat 16
4 Salting fish and meat 25
4.1 General information 25
4.2 Salting fish 26
4.3 Salting meat 32
4.4 Preparing salted fish and meat for consumption 36
5 Drying fish and meat 37
6 Smoking fish and meat 46
7 Fermenting fish 54
8 Canning fish and meat 64
9 Cooling and freezing fish and meat 78
Further reading 82
Useful addresses 84
This manual is a publication of Agromisa and covers the preservation of fruit and vegetables. It is available as a free pdf for online download and in print at a cost of 8.49 Euro from Agromisa.
from: Agromisa (click image to download)
The images below are clips from the manual and presented to help in illustrating the nature of the information.
- detailed background information is presented on spoilage and how various preservation methods operate
- practical information on fruit and vegetable preparation for preservation is provided
- heating, drying, pickling, salting and jam making are covered with practical and applicable information
- while equipment designs are not provided illustrations provide enough detail to allow a mechanically minded person to construct equipment
- some information is also provided on setting up an enterprises based on the technology described
- practical details (temp, dryer loading, losses, moisture & dryness test) are provided for a range of products
Following on the link to a simple overview by the GATE programme of GTZand the article on 3 different solar dryer designs a final article gives detailed design information and drawing for the cabinet dryer.
This document details constuction down to wood sizes, joint details and glass securement, detailed drawings and materials lists.
Following on the link to a simple overview by the GATE programme of GTZ, the article below gives practical details of three solar dryer designs.
from: GTZ GATE (click image for full story online)
This paper presents the characteristics of three solar driers. A 15 US$ tent drier, a 400 US$ box drier, and a 5,000 US$ tunnel drier are discussed.and then the drier is placed over them. The first day of drying should be sunny to produce a quality dried product.
The German Appropriate Technology and Ecoefficiency Programme (GATE) Programme of GTZ (the German Development Agency) has a good overview of sun drying as a food technology process.
from: GTZ – GATE (click image for full story online)
It presents the technical background of drying, describes and compares different drying operation and equipment, gives an idea of costs, tabulated advantages and disadvantages and gives a good list of references.
In this time of potential food shortages and rising energy cost, using the sun’s free energy to preserve food which might otherwise be wasted, is at first glance very attractive. The article provides some of the information needed to consider the pros and cons.
One should remember though that the bulk of the worlds dried fruit is sun dried and we have no concerns about its safely and quality.
Preservation of foods is central to any food processing operation and specially important to small scale processors as it simplifies logistics. Food Technologists know that preserving acidic foods is safer and easier than low acidity foods and more appropriate to small scale processing.
Food Science a joint venture between CSIRO and the government of Victoria has published this as part of their online information for SME processors.
It defines the range of products and their acidity and defines processes that can be used. It focusses on the proven fact that so long as a foods equilibrium pH is below 4.5 there is no chance of food poisoning. It describes the various types of food spoilage organisms and compares their survival / activity under the conditions of processing.