Apple juice by R.Borgacci

What is Apple Juice

General information on apple juice

Apple juice is a food obtained by isolating the liquid portion of apples, the fruits of the tree belonging to the genus Malus and pumila species (Family Rosaceae).

In appearance and nutritional properties, apple juice is a fruit juice in all respects.

It can be natural and home-made, obtained with different methods and tools (extractor, centrifuge, etc.), or commercially available (liquid, above all pasteurized, distributed in glass bottles and tetra brik, or frozen - also concentrated to be diluted).

Note : by definition, apple juice, extract and centrifuged are three different products. However, with regard to the few chemical and nutritional differences that distinguish them, in this article we will generally talk about the non-concentrated liquid obtained (regardless of the system) from the pulp of the apples.

Apple juice is considered to be a food, or rather a derivative, or a drink. The raw material, made up of apples of any variety, belongs to the VII fundamental group of foods. Apple juice is therefore a nutritional source of: water ( abundant ), fibers ( almost absent ), simple sugars (fructose), certain vitamins (especially vitamin C or ascorbic acid) and specific minerals (especially potassium and magnesium). Several organic acids are also abundant, not too significant from a nutritional point of view, but certainly important as regards oral hygiene.

Apple juice is consumed as a common non-alcoholic drink. In Italy, apple juice is served fresh or at room temperature; in many foreign countries instead it is common to heat it, especially in winter, and drink it as an herbal tea. Like pomegranate juice, apple juice has recently become more and more popular. Its growing notoriety, partly due to its nutritional properties, is also the result of an extremely effective marketing campaign.

Commercial apple juice

Commercial apple juice is obtained, like the homemade one, by squeezing the fruit and collecting the juice.

To make it transparent and completely free of solid residues, further processing processes are applied such as: centrifugation (mechanical separation), enzymatic clarification (chemical precipitation, mainly with the use of pectinase and amylase) and microfiltration. By eliminating the particles in suspension, ie pectin and starch, the apple juice becomes much clearer.

The problem of preservability remains. To obtain a long shelf life, apple juice is generally pasteurized. This system is based on raising the temperature just over 70 ° C for a period of time sufficient to eliminate microorganisms and inactivate fruit enzymes (not too long, thanks to the acid pH of the drink).

Insights

The US Food and Drug Administration (FDA) has established "safe" temperatures and pasteurization times to minimize (5 log) even the most resistant microorganisms, such as Cryptosporidium parvum and E. coli 0157 :

• 160 ° F (71 ° C) for at least 6 seconds
• 165 ° F (74 ° C) for at least 2.8 seconds
• 170 ° F (77 ° C) for at least 1.3 seconds
• 175 ° F (79 ° C) for at least 0.6 seconds
• 180 ° F (82 ° C) for at least 0.3 seconds.

To obtain concentrated apple juice instead, a heat treatment is applied which, by favoring the evaporation of water, dehydrates the drink.

To date, large retailers are not involved in the trade of raw and unfiltered apple juice. In Italy this is produced mainly locally, on a reduced scale, by small farms, located above all in Padania or in any case in the north.

Did you know that ...

Abroad, especially in the United States and Canada, unfiltered apple juice is marketed under the name "apple cider" (apple cider). In these places, the legal distinction between apple juice and apple cider is not yet well defined and with the same name you can find even very different products. In contrast, in New Zealand, Australia and the United Kingdom, apple cider means fermented fruit juice, usually obtained from apples but also from pears. In much of North America, this alcoholic beverage is known as "hard cider".

The absence of pasteurization, however, has both positive and negative aspects. It is good that, at room temperature, the portion of the thermolabile factors (for example vitamin C) remains completely free. On the other hand, we recall that many nutritional factors are potentially oxidizable (negative reaction to oxygen, free radicals, etc.), which is why a poorly preserved raw apple juice is still relatively impoverished. In contrast, pasteurized apple juice is already deprived of a slice of thermolabile nutrients but, due to the inactivation of cellular enzymes, most food aging processes are blocked (to the benefit of visual, organoleptic and taste characteristics, but partly also nutritional).

Nutritional Properties

Nutritional properties of natural apple juice

Apple juice is a derivative (drink) derived from the processing of apples, foods that belong to the VII fundamental group of foods (products rich in water, fiber, fructose, minerals and specific vitamins).

Did you know that ...

The difference between food and food derivative is a very important aspect, especially from the chemical and nutritional point of view. In this case, on 100 g of product the juice brings much more water than whole apples and much less fiber (present only in traces).

Commercial apple juice has a medium caloric intake, more or less similar to that of other sweet drinks (for example coca cola). The total energy is attributable mainly to soluble sugars, hence to fructose monosaccharide. Proteins and lipids, scarce even in whole apples, can be defined as almost irrelevant in the juice. Cholesterol is absent. The fibers are unfortunately marginal; on the contrary, they are entirely present in other fruit derivatives such as, for example, smoothies.

Insights

Dietary fibers, besides being excellent prebiotics - or "feeding" of the microbiota, the latter responsible for the nourishment and defense of the mucous membranes - represent nutritional factors necessary for the health of the intestine, favoring peristalsis (anti-constipation function) and keeping the intestine clean of toxins (factors predisposing to certain types of cancer).

From a vitamin point of view, apple juice offers an excellent amount of ascorbic acid or vitamin C, folic acid, carotenoids (or provitamin A - RAE - especially lutein and zeaxanthin) and choline.

Insights

Choline or vitamin J - of the B complex but not essential - performs important functions such as the formation of phospholipids in cell membranes and of the neurotransmitter acetylcholine. The "Food and Nutrition Board of the Institute of Medicine of the National Academy of Sciences" has established that the adequate minimum intake of choline is about 550 mg / day.

The most abundant mineral of apple juice is potassium; some consider the content of boron to be interesting (it participates in the health of the bones and therefore of the skeleton).

Apple juice also has a significant concentration of antioxidants other than vitamin C such as low molecular weight natural phenols (such as chlorogenic acid, flavan-3-ol and flavonols) and procyanidins. Apple juice has been shown to reduce oxidative stress on the brain (laboratory mice) during aging. Research suggests that apple juice increases the levels of acetylcholine in the brain, which can potentially improve memory.

In apple juice there are no molecules potentially responsible for common food intolerances, such as gluten, lactose and histamine. In sensitive subjects, apple juice can be responsible for an allergic form, which is also crusade with birch. The trend of birch allergy is quite heterogeneous and can affect, in limited areas, up to half of the population (eg in Northern Europe); in other places instead, it is reduced to not even 5% (for example in Spain). In Italy, birch allergy affects about 18-28% of subjects and each of these is potentially allergic to apples.

Apple juice is a drink that lends itself to most diets. Being rich in sugars, it must be taken with regard to overweight people, with hyperglycemia or type 2 diabetes mellitus, and with hypertriglyceridemia. It has no contraindication for hypercholesterolemics and hypertensives.

Fresh, raw and well preserved, due to its richness in folic acid, apple juice lends itself to nutrition during pregnancy. However, it should not be forgotten that, in the case of gestational diabetes, significant concentrations of fructose could contribute to worsening the clinical picture by increasing the related risks for the fetus (malformations) and the mother (evolution in type 2 diabetes mellitus).

In children at risk (for suspicion of allergic inheritance) it is advisable to pay close attention during the early stages of childhood, particularly in weaning.

Apple juice is perfectly suited to the diet of celiac, lactose intolerant and histamine. Those who have a poor tolerance to fructose (which generally manifests as diarrhea) should avoid it, especially on an empty stomach, or take it in small quantities.

It is perfectly suited to the sportsman's diet, which can take advantage of the characteristics of the drink - average index and glycemic load, wealth of water and potassium - in the pre or post-workout snack (depending on the case).

It has no contraindications in vegetarian, vegan and raw food (obviously, we always mean the raw one). It also seems to satisfy the criteria of all philosophies and religions.

As we will see in the next section, raw, fresh and preserved apple juice can have very significant hygienic implications.

The average portion of apple juice is 150 ml (about 70 kcal).

Apple juice and teeth

Apple juice contains fructose. This soluble sugar, although less than glucose, is metabolizable by the bacterial flora of the mouth. Nevertheless, apple juice is not considered one of the products that make tooth decay easier (like sweets).

Apple juice is also rich in acids, not directly involved in the formation of caries, but potentially responsible for the wear and tear of surface enamel. Let it be clear that malic acid, citric acid and tartaric acid do not significantly corrode the teeth. However, it has been shown that brushing the enamel immediately after eating, above all having introduced drinks and acid foods, an abrasive action with a negative effect is exercised. To avoid this side effect it would therefore be sufficient, before brushing your teeth, to rinse your mouth and wait at least 30 minutes from the end of the meal.

* The percentages (approximate) refer to the recommended US ration (US) for the adult population.

Safety

Being fruit juice, the population is led to think that it is a hygienically safe food. This is only partially true, or rather, only applies to pasteurized fruit juice.

Let's start by saying that raw apple juice should be kept in airtight containers, which do not allow light to shine through, inside the refrigerator (4 ° C) for a short period of time (depending on the product); if to taste, smell and a visual analysis it shows significant alterations, better to throw it.

In North America, from 2000 to 2010, over 1, 700 cases of foodborne illnesses were recorded due to the consumption of unpasteurized apple juice and cider. The pathogens responsible for these diseases included parasites, bacteria and viruses. The most common were: E.coli 0157 and 0111, Salmonella, Cryptosporidium, Clostridium botulinum and hepatitis A virus . These may have been spread in various ways, such as contamination of the fruit during cultivation (polluted water), transport in dirty containers or due to insufficient washing.

It is therefore strongly advised not to consume raw, unpasteurized apple juice (especially preserved), to people who are potentially at risk, such as pregnant women, very young children, the elderly and immunosuppressed.

Description

Description of the homemade raw apple juice

Homemade raw apple juice is a yellowish and watery liquid; aroma and flavor are characteristic and depend on the cultivar used (the Fuji apple juice, for example, is quite different from that of Granny Smith apple).

It has a naturally sweet taste, due to the presence of fructose, and slightly acidic, due to the density of organic acids (as we have said, consisting mainly of citric, malic and tartaric). It is not as sour as citrus juice but not as sweet as grape juice.

The intensity and variability of each of these characteristics depend above all on the type of apples used, hence the botanical variety of the plants, the climate of the current year and the degree of ripeness of the fruits.

The commercial apple juice of large retailers, on the other hand, besides being predominantly clear, also has uniformity and quality standards.

Trade

Commercial characteristics of apple juice

Commercial apple juice is mainly produced using the McIntosh cultivar; two medium-sized apples of this type contain about 200 ml of juice.

Among the main characteristics of apple juice, the most important is certainly the "naturalness".

The vast majority of commercial apple juices state on the label, in large letters, "without added sugar", or "without flavorings and colorings", or even "unfiltered". It is, as often happens, a very effective marketing strategy.

We start from the assumption that, as we have already said, the apple juice of the large retailers is subjected to pasteurization (therefore to an increase in temperatures). It must therefore be specified that, while not adding other sugars, it is possible to increase the sweetness of the food by prolonging or intensifying the heat treatment, making the water evaporate and therefore concentrating the liquid. This is obviously at the expense of the concentration of vitamin C and other thermolabile factors; ascorbic acid however, being also an antioxidant additive, can however be added later (E300, E301, E303, E304).

With regards to dyes, aromas and the application or not of filtration, there is nothing to highlight.

Highlighting the absence of sugars and certain added additives, or the absence of "processing" (which makes the idea of ​​an apple juice more "raw" and therefore "richer"), companies are able to draw on a basin more users, with different types of customers:

• Regular consumers of traditional fruit juices. They, however, conditioned by the growing interest in natural products, will choose to orient themselves towards foods with less sugar and calories (also for children, for the obese and for diabetics)
• Consumers always oriented towards the purchase of dietary, healthy, slimming or presumed products.

The world production of commercial apple juice is led by China, Poland, the United States and Germany.