Food Spill (Food Waste)
Curs
Proiect: The innovative blended learning concept for resource efficiency (RELeCo)
2014-1-RO01-KA203-002737
Cursul se bazează pe raportul HLPE - Food losses and waste in the context of sustainable food systems (2014), raportul FAO - Global food losses and food waste (2011) și raportul FAO - Food Wastage Footprint: Impacts on Natural Resources (2013).
5. The production of simple sugars of the polysaccharides
It is noticed that, generally, from 100 g of bakery waste substrate are obtained 80 g of glucose.
They contain polysaccharides such as starch, cellulose, arabinoxylan, β - glucans which, by chemical or
enzyme-catalyzed reactions can be converted to simple sugars (expression can be done in glucose
equivalents).
6. The production of organic acids from bakery waste
It is known that fermentations which take place in bread dough are alcoholic fermentation made
by yeast (primary fermentation) and lactic fermentation (realised by lactic bacteria existing in the
epiphytic microbiota of the wheat and rye flours). These microorganisms are, however, inactivated at
temperatures reached in the process of baking the bread dough. Waste resulting from the bakery process
can be, however, substrates for the action of bacterial species such as Lactobacillus amylovorus (able to
hydrolyze starch), and the addition of yeasts extract can increase the production of lactic acid resulting
from the fermentation activity of the microorganism.
7. Production of biofuel from bakery waste
These products can become in the future, extremly appealing in their recovery purposes as
biofuel. The term "biofuel" means the fuel in gaseous, liquid or solid form produced from biomass.
Biofuels include bioethanol, biomethanol, vegetable oils, biodiesel, biogas, biosynthetic gas, bio oils
etc.
Bioconversion of bakery waste requires the contribution of enzymes that have the ability to
hydrolyze cellulose and hemicelluloses to the stage of simple carbohydrates.
The superior valorification of stale bread and bakery waste
Bread as food, accounted for thousands of years, energy and protein basis of all civilizations of
the world from the beginning. Compositional structure of the bread reveals a preponderance of the
reserve polysaccharide of vegetables - starch - but also significant amounts of protein reserves (gluten
protein), pentosan, along with relatively small amounts of lipids, minerals and vitamins.
For accessibility of the informations presented below, it should be noticed that, compared to the
form that exists in grain raw materials, key components of bakery waste have a number of features
highlighted below:
1of oxidative
gelification of the dough, so that their enzymatic assailable grew.
Given these considerations, based on proposals made by Meuser and Martens (2009 ), it is
proposed for bakery units, a model of superior valorification of stale bread and bakery waste.
The waste, previously crushed, are mixed in a ratio of 1:2 with water in a vessel (tank) provided
with a heating system.
Fig. 18. The graphical representation of the responses to the question 20
of the Questionnaire "Food Waste"
The addition of α - amylase (heat resistent enzyme) is initiated structural disruption of the starch
and its liquefaction takes place, the process being carried out at 70° C and pH 5.2 for 3 hours. By α –
amylase action it’s obtained a large amount of dextrin and low amount of simple carbohydrates. The
transformation of the starch initiated by α – amylase is continued by the addition of amyloglucosidase
which continues the hydrolysis of the previously obtained products until obtaining glucose.
Saccharification process is carried out at 60° C for 16 hours, thus being hydrolyzed at least 80 % of the
original starch. As mentioned previously, liquefaction and saccharification process of the starch
develops faster because it suffered during bread baking, a gelatinization process, in this way, easier to
be attacked by amylolitic enzymes.
Further, the existing proteins in the medium can be hydrolyzed by using a proteolytic enzyme
preparation with endo- and exopeptidase action which converts the protein substrate in peptides with
low molecular weight and amino acids. The process is carried out at 45° C, pH 5.2, approximately 21
hours, during which time 70% of the proteins are hydrolyzed. The proteolytic enzymes are then
subsequently inactivated.
After proteolysis it can be made an operation for separation and decantation, obtaining a solid
residue (consisting mainly of the fibers but not only) which represents a good feed and a suspension
that will be inoculated with Lactobacillus delbrüeckii. Lactic fermentation carried out by the bacteria
2
leads to the accumulation of lactic acid (the main product) and acetic acid (by-product) which, over a
period of about 24 hours, the pH of the medium decreases until reaching a pH value of 4. Bringing the
pH of the medium at this value is necessary to create optimal conditions for yeast activity that will
make the subsequent fermentative processes.
Food Spill (Food Waste)
Curs
Proiect: The innovative blended learning concept for resource efficiency (RELeCo)
2014-1-RO01-KA203-002737
Cursul se bazează pe raportul HLPE - Food losses and waste in the context of sustainable food systems (2014), raportul FAO - Global food losses and food waste (2011) și raportul FAO - Food Wastage Footprint: Impacts on Natural Resources (2013).
5. The production of simple sugars of the polysaccharides
It is noticed that, generally, from 100 g of bakery waste substrate are obtained 80 g of glucose.
They contain polysaccharides such as starch, cellulose, arabinoxylan, β - glucans which, by chemical or
enzyme-catalyzed reactions can be converted to simple sugars (expression can be done in glucose
equivalents).
6. The production of organic acids from bakery waste
It is known that fermentations which take place in bread dough are alcoholic fermentation made
by yeast (primary fermentation) and lactic fermentation (realised by lactic bacteria existing in the
epiphytic microbiota of the wheat and rye flours). These microorganisms are, however, inactivated at
temperatures reached in the process of baking the bread dough. Waste resulting from the bakery process
can be, however, substrates for the action of bacterial species such as Lactobacillus amylovorus (able to
hydrolyze starch), and the addition of yeasts extract can increase the production of lactic acid resulting
from the fermentation activity of the microorganism.
7. Production of biofuel from bakery waste
These products can become in the future, extremly appealing in their recovery purposes as
biofuel. The term "biofuel" means the fuel in gaseous, liquid or solid form produced from biomass.
Biofuels include bioethanol, biomethanol, vegetable oils, biodiesel, biogas, biosynthetic gas, bio oils
etc.
Bioconversion of bakery waste requires the contribution of enzymes that have the ability to
hydrolyze cellulose and hemicelluloses to the stage of simple carbohydrates.
The superior valorification of stale bread and bakery waste
Bread as food, accounted for thousands of years, energy and protein basis of all civilizations of
the world from the beginning. Compositional structure of the bread reveals a preponderance of the
reserve polysaccharide of vegetables - starch - but also significant amounts of protein reserves (gluten
protein), pentosan, along with relatively small amounts of lipids, minerals and vitamins.
For accessibility of the informations presented below, it should be noticed that, compared to the
form that exists in grain raw materials, key components of bakery waste have a number of features
highlighted below:
1of oxidative
gelification of the dough, so that their enzymatic assailable grew.
Given these considerations, based on proposals made by Meuser and Martens (2009 ), it is
proposed for bakery units, a model of superior valorification of stale bread and bakery waste.
The waste, previously crushed, are mixed in a ratio of 1:2 with water in a vessel (tank) provided
with a heating system.
Fig. 18. The graphical representation of the responses to the question 20
of the Questionnaire "Food Waste"
The addition of α - amylase (heat resistent enzyme) is initiated structural disruption of the starch
and its liquefaction takes place, the process being carried out at 70° C and pH 5.2 for 3 hours. By α –
amylase action it’s obtained a large amount of dextrin and low amount of simple carbohydrates. The
transformation of the starch initiated by α – amylase is continued by the addition of amyloglucosidase
which continues the hydrolysis of the previously obtained products until obtaining glucose.
Saccharification process is carried out at 60° C for 16 hours, thus being hydrolyzed at least 80 % of the
original starch. As mentioned previously, liquefaction and saccharification process of the starch
develops faster because it suffered during bread baking, a gelatinization process, in this way, easier to
be attacked by amylolitic enzymes.
Further, the existing proteins in the medium can be hydrolyzed by using a proteolytic enzyme
preparation with endo- and exopeptidase action which converts the protein substrate in peptides with
low molecular weight and amino acids. The process is carried out at 45° C, pH 5.2, approximately 21
hours, during which time 70% of the proteins are hydrolyzed. The proteolytic enzymes are then
subsequently inactivated.
After proteolysis it can be made an operation for separation and decantation, obtaining a solid
residue (consisting mainly of the fibers but not only) which represents a good feed and a suspension
that will be inoculated with Lactobacillus delbrüeckii. Lactic fermentation carried out by the bacteria
2
leads to the accumulation of lactic acid (the main product) and acetic acid (by-product) which, over a
period of about 24 hours, the pH of the medium decreases until reaching a pH value of 4. Bringing the
pH of the medium at this value is necessary to create optimal conditions for yeast activity that will
make the subsequent fermentative processes.
Contents
1. Food Spill (Food Waste) – Problemă Vitală a Societății Contemporane / 12. Definirea termenilor specifici utilizați / 11
3. Tipuri de pierderi și deșeuri alimentare / 18
4. Cauzele apariției pierderilor de alimente și a deșeurilor alimentare / 28
5. Impactul deșeurilor alimentare asupra resurselor naturale / 58
6. Modalități de reducere a pierderilor de alimente și deșeurilor alimentare / 89
1
Food Spill (Food Waste) – Problemă
Vitală a Societăţii Contemporane
1.1. Introducere
În lumea actuală, în contextul în care multe persoane nu au suficientă hrană iar resursele sunt limitate, este fundamental ca tema prevenirii, reducerii pierderilor și a risipei de alimente să constituie o temă de interes major.
Pierderile și risipa de alimente trebuie să fie analizate într-o perspectivă globală, de la stadiul de producție până la cel de consum, integrând verigile intermediare precum prelucrarea și distribuția, inclusiv cateringul din afara gospodăriilor. Există, incă, o serie de confuzii cu privire la definițiile expresiilor „risipă de alimente” și „deșeuri biologice”. Prin „risipă de alimente” se ințelege, in mod obișnuit, totalitatea produselor alimentare eliminate din lanțul de aprovizionare cu alimente din motive economice ori estetice sau din cauza apropierii datei de expirare, care sunt insă perfect comestibile, pot fi destinate în continuare consumului și care, in lipsa unei posibile intrebuințări alternative, sunt eliminate, producând efecte negative din punct de vedere ecologic, al costurilor economice și al pierderilor de venit suferite de întreprinderi.
Pierderile și risipa de alimente ar putea fi definite ca referindu-se la orice produs, inițial destinat consumului uman, cu excepția produselor nealimentare, care este aruncat sau distrus la toate nivelurile lanțului alimentar, de la fermă la consumator. Potrivit definiției FAO, pierderile alimentare sunt observate la începutul lanțului alimentar (producția primară, etapele post-recoltare și prelucrarea), în timp ce risipa de alimente se înregistrează mai degrabă la sfârșitul lanțului (etapele distribuției și consumului final). Astfel, reziduurile recoltelor și produsele necomestibile secundare rezultate din prelucrare, nu fac parte din conceptul de pierderi sau de risipă de alimente. Cu toate acestea, ceea ce în prezent nu este comestibil și nu poate fi transformat în produs secundar, ar putea deveni un astfel de produs în viitor, în funcție de progresele cunoașterii și ale tehnicii. De asemenea, aceste definiții trebuie considerate ca fiind evolutive.
Chiar dacă practicile comerciale vizează în primul rând să încurajeze cumpărăturile, unele ar putea fi și un factor de accentuare a anumitor forme de risipă (de exemplu, comunicarea legată exclusiv de preț - trei produse la preț de două etc.). Dar și aici anchetele sociologice constată diferențe de comportament semnificative, în funcție de profilul familial.
Pe de altă parte, în rândul consumatorilor există un grad foarte ridicat de confuzie între „data limită de consum” și „data limită de utilizare optimă”, ceea ce contribuie la risipa de alimente. În Marea Britanie, cercetările întreprinse asupra etichetării arată că între 45% și 49% dintre consumatori interpretează greșit datele de valabilitate a produselor, ceea ce atrage după sine o risipă de 20% alimente, total evitabilă [WRAP – Waste and Resources Action Programme (Programul de acțiune pentru deșeuri și resurse)]. De aceea, comunicarea cu consumatorii este în mod evident esențială și pertinența sa decurge dintr-o analiză corectă a cauzelor risipei. În afară de o sensibilizare generală asupra efectelor acestui fenomen, un accent deosebit trebuie pus, printre altele, pe interpretarea corecta a datelor de valabilitate a produselor, de planificare a cumpărăturilor, de depozitare corespunzatoare a alimentelor și de valorificare a resturilor alimentare.
Formarea joacă un rol important în problema reducerii risipei de alimente și este dezirabil ca această tematică să fie inclusă în planurile de invatamant ale viitorilor ingineri din industria alimentara, ale specialiștilor în catering public și privat, precum și în cursurile lor de formare continuă. Aceasta ar putea fi aplicata și în școlile de designeri de ambalaje în ceea ce privește conservarea alimentelor și utilizarea la maxim a conținutului lor.
Agricultura, prin natura sa, poate avea un rol fundamental și de pionierat in combaterea risipei de alimente. Prin urmare, trebuie introduse măsuri ambițioase in acest sens referitoare la agricultură, comerț și distribuția produselor alimentare si, de asemenea, întreprinse acțiuni in materie de investiții in domeniile cercetării, științei, tehnologiei, educației, consilierii și inovării in agricultură, in vederea reducerii risipei de alimente și a educării și stimulării consumatorilor să adopte un comportament mai conștient și mai responsabil pentru a preveni risipa de alimente.
1.2. Pierderile și risipa de alimente – o problema globală